@article {199, title = {Towards biomarker-based tests that can facilitate decisions about prevention and management of preeclampsia in low-resource settings.}, journal = {Clin Chem Lab Med}, year = {2015}, month = {2015 May 20}, abstract = {

In recent years, an increasing amount of literature is emerging on candidate urine and blood-based biomarkers associated with incidence and severity of preeclampsia (PE) in pregnant women. While enthusiasm on the usefulness of several of these markers in predicting PE is evolving, essentially all work so far has focused on the needs of high-resource settings and high-income countries, resulting primarily in multi-parameter laboratory assays based on proteomic and metabolomics analysis techniques. These highly complex methods, however, require laboratory capabilities that are rarely available or affordable in low-resource settings (LRS). The importance of quantifying maternal and perinatal risks and identifying which pregnancies can be safely prolonged is also much greater in LRS, where intensive care facilities that can rapidly respond to PE-related health threats for women and infants are limited. For these reasons, simple, low cost, sensitive, and specific point-of-care (POC) tests are needed that can be performed by antenatal health care providers in LRS and that can facilitate decisions about detection and management of PE. Our study aims to provide a comprehensive systematic review of current and emerging blood and urine biomarkers for PE, not only on the basis of their clinical performance, but also of their suitability to be used in LRS-compatible test formats, such as lateral flow and other variants of POC rapid assays.

}, issn = {1434-6621}, doi = {10.1515/cclm-2015-0069}, author = {Acestor, Nathalie and Goett, Jane and Lee, Arthur and Herrick, Tara M and Engelbrecht, Susheela M and Harner-Jay, Claudia M and Howell, Bonnie J and Weigl, Bernhard H} } @patent {marsot_united_2015, title = {United {States} {Patent}: 8945910 - {Method} and apparatus for an improved sample capture device}, number = {8945910}, year = {2015}, month = {feb}, abstract = {A body fluid sampling device is provided. A mesh (120) may be used to guide blood or fluid to travel directly form the wound to an analyte detecting port on the cartridge (121). Thus the volume of blood or body fluid produced at the wound site irregardless of its droplet geometry can be reliable and substantially completely transported to the analyte detecting member (150) for measurement.}, url = {http://patft.uspto.gov/netacgi/nph-Parser?Sect1=PTO2\&Sect2=HITOFF\&p=1\&u=\%2Fnetahtml\%2FPTO\%2Fsearch-bool.html\&r=2\&f=G\&l=50\&co1=AND\&d=PTXT\&s1=\%22Bardell\%3B+Ron\%22.INNM.\&OS=IN/\%22Bardell;+Ron\%22\&RS=IN/\%22Bardell;+Ron\%22}, author = {Marsot, Travis and Lum, Paul and Alden, Don and Ross, James and Bardell, Ron L. and Weigl, Bernhard Hans} } @patent {kelley_united_2015, title = {United {States} {Patent}: 8980635 - {Disposable} cartridge for fluid analysis}, number = {8980635}, year = {2015}, month = {mar}, abstract = {A disposable blood analysis cartridge may include a sample collection reservoir, an absorbance measurement channel, and an optical light scattering measurement channel. One or more valves may be disposed between the sample collection reservoir and the absorbance measurement channel and/or the optical light scattering measurement channel. A negative pressure may be applied to the cartridge to pull sample from the sample collection reservoir through the one or more valves and into the absorbance measurement channel and/or the optical light scattering measurement channel. Once the sample is pulled into the absorbance measurement channel and/or the optical light scattering measurement channel, the one or more valves may be closed. With the one or more valves closed, and in some cases, a pusher fluid may be provided to push the fluid sample to other regions of the disposable fluid blood analysis cartridge.}, url = {http://patft.uspto.gov/netacgi/nph-Parser?Sect1=PTO2\&Sect2=HITOFF\&p=1\&u=\%2Fnetahtml\%2FPTO\%2Fsearch-bool.html\&r=1\&f=G\&l=50\&co1=AND\&d=PTXT\&s1=\%22Bardell\%3B+Ron\%22.INNM.\&OS=IN/\%22Bardell;+Ron\%22\&RS=IN/\%22Bardell;+Ron\%22}, author = {Kelley, Mark and Bardell, Ron and Janisch, Robert and Wong, Pamela and Peltola, Eric} } @article {200, title = {Electricity-free amplification and detection for molecular point-of-care diagnosis of HIV-1.}, journal = {PLoS One}, volume = {9}, year = {2014}, month = {2014}, pages = {e113693}, abstract = {

In resource-limited settings, the lack of decentralized molecular diagnostic testing and sparse access to centralized medical facilities can present a critical barrier to timely diagnosis, treatment, and subsequent control and elimination of infectious diseases. Isothermal nucleic acid amplification methods, including reverse transcription loop-mediated isothermal amplification (RT-LAMP), are well-suited for decentralized point-of-care molecular testing in minimal infrastructure laboratories since they significantly reduce the complexity of equipment and power requirements. Despite reduced complexity, however, there is still a need for a constant heat source to enable isothermal nucleic acid amplification. This requirement poses significant challenges for laboratories in developing countries where electricity is often unreliable or unavailable. To address this need, we previously developed a low-cost, electricity-free heater using an exothermic reaction thermally coupled with a phase change material. This heater achieved acceptable performance, but exhibited considerable variability. Furthermore, as an enabling technology, the heater was an incomplete diagnostic solution. Here we describe a more precise, affordable, and robust heater design with thermal standard deviation <0.5{\textdegree}C at operating temperature, a cost of approximately US$.06 per test for heater reaction materials, and an ambient temperature operating range from 16{\textdegree}C to 30{\textdegree}C. We also pair the heater with nucleic acid lateral flow (NALF)-detection for a visual readout. To further illustrate the utility of the electricity-free heater and NALF-detection platform, we demonstrate sensitive and repeatable detection of HIV-1 with a {\ss}-actin positive internal amplification control from processed sample to result in less than 80 minutes. Together, these elements are building blocks for an electricity-free platform capable of isothermal amplification and detection of a variety of pathogens.

}, issn = {1932-6203}, doi = {10.1371/journal.pone.0113693}, author = {Singleton, Jered and Osborn, Jennifer L and Lillis, Lorraine and Hawkins, Kenneth and Guelig, Dylan and Price, Will and Johns, Rachel and Ebels, Kelly and Boyle, David and Weigl, Bernhard and LaBarre, Paul} } @article {201, title = {Medical devices and diagnostics for cardiovascular diseases in low-resource settings.}, journal = {J Cardiovasc Transl Res}, volume = {7}, year = {2014}, month = {2014 Nov}, pages = {737-48}, abstract = {

Noncommunicable diseases (NCDs), including cardiovascular diseases and diabetes, have emerged as an underappreciated health threat with enormous economic and public health implications for populations in low-resource settings. In order to address these diseases, devices that are to be used in low-resource settings have to conform to requirements that are generally more challenging than those developed for traditional markets. Characteristics and issues that must be considered when working in low- and middle-income countries (LMICs) include challenging environmental conditions, a complex supply chain, sometimes inadequate operator training, and cost. Somewhat counterintuitively, devices for low-resource setting (LRS) markets need to be of at least as high quality and reliability as those for developed countries to be setting-appropriate and achieve impact. Finally, the devices need to be designed and tested for the populations in which they are to be used in order to achieve the performance that is needed. In this review, we focus on technologies for primary and secondary health-care settings and group them according to the continuum of care from prevention to treatment.

}, keywords = {Biomedical Technology, Blood Chemical Analysis, Cardiovascular Diseases, Cost-Benefit Analysis, Developing Countries, Diabetes Mellitus, Diagnostic Techniques, Cardiovascular, Equipment Design, Health Care Costs, Health Resources, Health Services Accessibility, Health Services Needs and Demand, Humans, Predictive Value of Tests}, issn = {1937-5395}, doi = {10.1007/s12265-014-9591-3}, author = {McGuire, Helen and Weigl, Bernhard H} } @patent {kelley_united_2014, title = {United {States} {Patent}: 8663583 - {Disposable} cartridge for fluid analysis}, number = {8663583}, year = {2014}, month = {mar}, abstract = {A disposable blood analysis cartridge may include a sample collection reservoir, an absorbance measurement channel, and an optical light scattering measurement channel. One or more valves may be disposed between the sample collection reservoir and the absorbance measurement channel and/or the optical light scattering measurement channel. A negative pressure may be applied to the cartridge to pull sample from the sample collection reservoir through the one or more valves and into the absorbance measurement channel and/or the optical light scattering measurement channel. Once the sample is pulled into the absorbance measurement channel and/or the optical light scattering measurement channel, the one or more valves may be closed. With the one or more valves closed, and in some cases, a pusher fluid may be provided to push the fluid sample to other regions of the disposable fluid blood analysis cartridge.}, url = {http://patft.uspto.gov/netacgi/nph-Parser?Sect1=PTO2\&Sect2=HITOFF\&p=1\&u=\%2Fnetahtml\%2FPTO\%2Fsearch-bool.html\&r=7\&f=G\&l=50\&co1=AND\&d=PTXT\&s1=\%22Bardell\%3B+Ron\%22.INNM.\&OS=IN/\%22Bardell;+Ron\%22\&RS=IN/\%22Bardell;+Ron\%22}, author = {Kelley, Mark and Bardell, Ron and Janisch, Robert and Wong, Pam and Peltola, Eric} } @patent {saltsman_united_2014, title = {United {States} {Patent}: 8697009 - {Microfluidic} devices for fluid manipulation and analysis}, number = {8697009}, year = {2014}, month = {apr}, abstract = {The present invention relates to microfluidic devices and methods for manipulating and analyzing fluid samples. The disclosed microfluidic devices utilize a plurality of microfluidic channels, inlets, valves, filter, pumps, liquid barriers and other elements arranged in various configurations to manipulate the flow of a fluid sample in order to prepare such sample for analysis.}, url = {http://patft.uspto.gov/netacgi/nph-Parser?Sect1=PTO2\&Sect2=HITOFF\&p=1\&u=\%2Fnetahtml\%2FPTO\%2Fsearch-bool.html\&r=3\&f=G\&l=50\&co1=AND\&d=PTXT\&s1=\%22Weigl\%3B+Bernhard\%22.INNM.\&OS=IN/\%22Weigl;+Bernhard\%22\&RS=IN/\%22Weigl;+Bernhard\%22}, author = {Saltsman, Patrick and Shen, Mingchao and Houkal, Jeffrey M. and Lancaster, Christy A. and Battrell, C. Frederick and Weigl, Bernhard H.} } @patent {bardell_united_2014-1, title = {United {States} {Patent}: 8741233 - {Disposable} cartridge for fluid analysis}, number = {8741233}, year = {2014}, month = {jun}, abstract = {A disposable blood analysis cartridge for analyzing a blood sample including an optical light scattering measurement channel is described. In use, processed sample may be introduced into a sheath fluid channel at an angle, .alpha., of approximately 90 degrees, relative to the direction of flow of the sheath fluid. In addition, delivering the sample from the side into the sheath fluid may facilitate better positioning of the core within the hydrodynamic focusing channel for measurement.}, url = {http://patft.uspto.gov/netacgi/nph-Parser?Sect1=PTO2\&Sect2=HITOFF\&p=1\&u=\%2Fnetahtml\%2FPTO\%2Fsearch-bool.html\&r=6\&f=G\&l=50\&co1=AND\&d=PTXT\&s1=\%22Bardell\%3B+Ron\%22.INNM.\&OS=IN/\%22Bardell;+Ron\%22\&RS=IN/\%22Bardell;+Ron\%22}, author = {Bardell, Ron and Wang, Tzu-Yu and Washa, Mark} } @patent {wang_united_2014, title = {United {States} {Patent}: 8741234 - {Disposable} cartridge for fluid analysis}, number = {8741234}, year = {2014}, month = {jun}, abstract = {A disposable blood analysis cartridge for analyzing a blood sample including an optical absorbance measurement channel is described. The optical absorbance measurement channel includes a plasma separation region and at least one sub channel including a cuvette that is in fluid communication with the plasma separation region and configured to receive a plasma portion of a blood sample that has been passed through the plasma separation region. A negative pressure may be applied to the cartridge to draw the sample through the plasma separation region and into the sub channel including the cuvette.}, url = {http://patft.uspto.gov/netacgi/nph-Parser?Sect1=PTO2\&Sect2=HITOFF\&p=1\&u=\%2Fnetahtml\%2FPTO\%2Fsearch-bool.html\&r=5\&f=G\&l=50\&co1=AND\&d=PTXT\&s1=\%22Bardell\%3B+Ron\%22.INNM.\&OS=IN/\%22Bardell;+Ron\%22\&RS=IN/\%22Bardell;+Ron\%22}, author = {Wang, Tzu-Yu and Bardell, Ron and Seifried, Lynn} } @patent {janisch_united_2014, title = {United {States} {Patent}: 8741235 - {Two} step sample loading of a fluid analysis cartridge}, number = {8741235}, year = {2014}, month = {jun}, abstract = {A two-step method for loading a fluid sample into a disposable fluid analysis cartridge is described. First, capillary action may be used to initially draw a sample through a sample introduction port and into a sample collection reservoir provided in the fluid analysis cartridge. Once the fluid sample has been drawn into the sample collection reservoir by capillary action, a negative pressure may be applied to the cartridge to pull the sample from the sample collection reservoir and into a sample loading channel. A valve may be disposed between the sample collection reservoir and the sample loading channel to prevent backflow of sample into the sample collection reservoir and to retain sample in the sample loading channel.}, url = {http://patft.uspto.gov/netacgi/nph-Parser?Sect1=PTO2\&Sect2=HITOFF\&p=1\&u=\%2Fnetahtml\%2FPTO\%2Fsearch-bool.html\&r=4\&f=G\&l=50\&co1=AND\&d=PTXT\&s1=\%22Bardell\%3B+Ron\%22.INNM.\&OS=IN/\%22Bardell;+Ron\%22\&RS=IN/\%22Bardell;+Ron\%22}, author = {Janisch, Robert and Wong, Pam and Peltola, Eric and Bardell, Ron and Kelley, Mark} } @patent {bardell_united_2014, title = {United {States} {Patent}: 8828320 - {Portable} sample analyzer cartridge}, number = {8828320}, year = {2014}, month = {sep}, abstract = {A system relating to sample analyzers, and more particular, to sample analyzers that are simple to operate and have a reduced risk of providing an erroneous result to a user. In some cases, the sample analyzer may be a portable sample analyzer that includes a disposable fluidic cartridge. The operators of the analyzers need not be trained.}, url = {http://patft.uspto.gov/netacgi/nph-Parser?Sect1=PTO2\&Sect2=HITOFF\&p=1\&u=\%2Fnetahtml\%2FPTO\%2Fsearch-bool.html\&r=3\&f=G\&l=50\&co1=AND\&d=PTXT\&s1=\%22Bardell\%3B+Ron\%22.INNM.\&OS=IN/\%22Bardell;+Ron\%22\&RS=IN/\%22Bardell;+Ron\%22}, author = {Bardell, Ron L. and Padmanabhan, Aravind and Reutiman, Peter L. and Rezachek, Tom M. and Cox, James A. and Fritz, Bernard S. and Cabuz, Cleopatra} } @article {203, title = {Field evaluation of a prototype paper-based point-of-care fingerstick transaminase test.}, journal = {PLoS One}, volume = {8}, year = {2013}, month = {2013}, pages = {e75616}, abstract = {

Monitoring for drug-induced liver injury (DILI) via serial transaminase measurements in patients on potentially hepatotoxic medications (e.g., for HIV and tuberculosis) is routine in resource-rich nations, but often unavailable in resource-limited settings. Towards enabling universal access to affordable point-of-care (POC) screening for DILI, we have performed the first field evaluation of a paper-based, microfluidic fingerstick test for rapid, semi-quantitative, visual measurement of blood alanine aminotransferase (ALT). Our objectives were to assess operational feasibility, inter-operator variability, lot variability, device failure rate, and accuracy, to inform device modification for further field testing. The paper-based ALT test was performed at POC on fingerstick samples from 600 outpatients receiving HIV treatment in Vietnam. Results, read independently by two clinic nurses, were compared with gold-standard automated (Roche Cobas) results from venipuncture samples obtained in parallel. Two device lots were used sequentially. We demonstrated high inter-operator agreement, with 96.3\% (95\% C.I., 94.3-97.7\%) agreement in placing visual results into clinically-defined "bins" (<3x, 3-5x, and >5x upper limit of normal), >90\% agreement in validity determination, and intraclass correlation coefficient of 0.89 (95\% C.I., 0.87-0.91). Lot variability was observed in \% invalids due to hemolysis (21.1\% for Lot 1, 1.6\% for Lot 2) and correlated with lots of incorporated plasma separation membranes. Invalid rates <1\% were observed for all other device controls. Overall bin placement accuracy for the two readers was 84\% (84.3\%/83.6\%). Our findings of extremely high inter-operator agreement for visual reading-obtained in a target clinical environment, as performed by local practitioners-indicate that the device operation and reading process is feasible and reproducible. Bin placement accuracy and lot-to-lot variability data identified specific targets for device optimization and material quality control. This is the first field study performed with a patterned paper-based microfluidic device and opens the door to development of similar assays for other important analytes.

}, keywords = {Alanine Transaminase, Blood Chemical Analysis, Developing Countries, Drug Monitoring, Drug-Induced Liver Injury, Humans, Liver Function Tests, Microfluidics, Observer Variation, Paper, Point-of-Care Systems, Vietnam}, issn = {1932-6203}, doi = {10.1371/journal.pone.0075616}, author = {Pollock, Nira R and McGray, Sarah and Colby, Donn J and Noubary, Farzad and Nguyen, Huyen and Nguyen, The Anh and Khormaee, Sariah and Jain, Sidhartha and Hawkins, Kenneth and Kumar, Shailendra and Rolland, Jason P and Beattie, Patrick D and Chau, Nguyen V and Quang, Vo M and Barfield, Cori and Tietje, Kathy and Steele, Matt and Weigl, Bernhard H} } @article {205, title = {Instrument-free exothermic heating with phase change temperature control for paper microfluidic devices.}, journal = {Proc SPIE Int Soc Opt Eng}, volume = {8615}, year = {2013}, month = {2013 Mar 9}, pages = {86150R}, abstract = {

Many infectious diseases, as well as some cancers, that affect global health are most accurately diagnosed through nucleic acid amplification and detection. There is a great need to simplify nucleic acid-based assay systems for use in global health in low-resource settings as well as in settings that do not have convenient access to laboratory staff and equipment such as doctors{\textquoteright} offices and home care settings. In developing countries, unreliable electric power, inadequate supply chains, and lack of maintenance for complex diagnostic instruments are all common infrastructure shortfalls. Many elements of instrument-free, disposable, nucleic acid amplification assays have been demonstrated in recent years. However, the problem of instrument-free, low-cost, temperature-controlled chemical heating remains unsolved. In this paper we present the current status and results of work towards developing disposable, low-cost, temperature-controlled heaters designed to support isothermal nucleic acid amplification assays that are integrated with a two-dimensional paper network. Our approach utilizes the heat generated through exothermic chemical reactions and controls the heat through use of engineered phase change materials to enable sustained temperatures required for nucleic acid amplification. By selecting appropriate exothermic and phase change materials, temperatures can be controlled over a wide range, suitable for various isothermal amplification methods, and maintained for over an hour at an accuracy of +/- 1{\textdegree}C.

}, issn = {0277-786X}, doi = {10.1117/12.2005928}, author = {Singleton, Jered and Zentner, Chris and Buser, Josh and Yager, Paul and LaBarre, Paul and Weigl, Bernhard H} } @article {204, title = {Molecular diagnostics in a teacup: Non-Instrumented Nucleic Acid Amplification (NINA) for rapid, low cost detection of Salmonella enterica.}, journal = {Chin Sci Bull}, volume = {58}, year = {2013}, month = {2013 Apr}, pages = {1162-1168}, abstract = {

We report on the use of a novel non-instrumented platform to enable a Loop Mediated isothermal Amplification (LAMP) based assay for Salmonella enterica. Heat energy is provided by addition of a small amount (<150 g) of boiling water, and the reaction temperature is regulated by storing latent energy at the melting temperature of a lipid-based engineered phase change material. Endpoint classification of the reaction is achieved without opening the reaction tube by observing the fluorescence of sequence-specific FRET-based assimilating probes with a simple handheld fluorometer. At or above 22{\textdegree}C ambient temperature the non-instrumented devices could maintain reactions above a threshold temperature of 61{\textdegree}C for over 90 min-significantly longer than the 60 min reaction time. Using the simple format, detection limits were less than 20 genome copies for reactions run at ambient temperatures ranging from 8 to 36{\textdegree}C. When used with a pre-enrichment step and non-instrumented DNA extraction device, trace contaminations of Salmonella in milk close to 1 CFU/mL could be reliably detected. These findings illustrate that the non- instrumented amplification approach is a simple, viable, low-cost alternative for field-based food and agricultural diagnostics or clinical applications in developing countries.

}, issn = {1001-6538}, author = {Kubota, Ryo and LaBarre, Paul and Weigl, Bernhard H and Li, Yong and Haydock, Paul and Jenkins, Daniel M} } @article {202, title = {Point-of-Care Diagnostics in Low-Resource Settings and Their Impact on Care in the Age of the Noncommunicable and Chronic Disease Epidemic.}, journal = {J Lab Autom}, volume = {19}, year = {2013}, month = {2013 Dec 23}, pages = {248-257}, abstract = {

The emergence of point-of-care (POC) diagnostics specifically designed for low-resource settings coupled with the rapid increase in need for routine care of patients with chronic diseases should prompt reconsideration of how health care can be delivered most beneficially and cost-effectively in developing countries. Bolstering support for primary care to provide rapid and appropriate integrated acute and chronic care treatment may be a possible solution. POC diagnostics can empower local and primary care providers and enable them to make better clinical decisions. This article explores the opportunity for POC diagnostics to strengthen primary care and chronic disease diagnosis and management in a low-resource setting (LRS) to deliver appropriate, consistent, and integrated care. We analyze the requirements of resource-appropriate chronic disease care, the characteristics of POC diagnostics in LRS versus the developed world, the many roles of diagnostics in the care continuum in LRS, and the process and economics of developing LRS-compatible POC diagnostics.

}, issn = {2211-0682}, doi = {10.1177/2211068213515246}, author = {Weigl, Bernhard H and Neogi, Tina and McGuire, Helen} } @patent {padmanabhan_united_2013-1, title = {United {States} {Patent}: 8383043 - {Analyzer} system}, number = {8383043}, year = {2013}, abstract = {A system relating to sample analyzers, and more particular, to sample analyzers that are simple to operate and have a reduce risk of providing an erroneous result to a user. In some cases, the sample analyzer may be a portable sample analyzer that includes a disposable fluidic cartridge. The operators of the analyzers need not be trained.}, url = {http://patft.uspto.gov/netacgi/nph-Parser?Sect1=PTO2\&Sect2=HITOFF\&p=1\&u=\%2Fnetahtml\%2FPTO\%2Fsearch-bool.html\&r=9\&f=G\&l=50\&co1=AND\&d=PTXT\&s1=\%22Bardell\%3B+Ron\%22.INNM.\&OS=IN/\%22Bardell;+Ron\%22\&RS=IN/\%22Bardell;+Ron\%22}, author = {Padmanabhan, Aravind and Cox, James A. and Fritz, Bernard S. and Rezachek, Tom M. and Reutiman, Peter L. and Bardell, Ron L. and Cabuz, Cleopatra} } @patent {padmanabhan_united_2013, title = {United {States} {Patent}: 8518328 - {Fluid} sensing and control in a fluidic analyzer}, number = {8518328}, year = {2013}, abstract = {Instrument-cartridge interfaces for fluidic analyzers that have an instrument and a removable cartridge are disclosed. For example, and in one illustrative embodiment, the instrument may include a needle that is adapted to penetrate a septum on a removable cartridge. In another illustrative embodiment, the instrument may include a plunger that is adapted to deform a deformable membrane on a removable cartridge. In yet another illustrative embodiment, the instrument may include a nozzle that is adapted to mate and seal with a flow channel on a removable cartridge. Techniques for detecting the flow rate in a flow channel on a removable cartridge, as well as the position of fluid in a flow channel of a removable cartridge, are also disclosed.}, url = {http://patft.uspto.gov/netacgi/nph-Parser?Sect1=PTO2\&Sect2=HITOFF\&p=1\&u=\%2Fnetahtml\%2FPTO\%2Fsearch-bool.html\&r=8\&f=G\&l=50\&co1=AND\&d=PTXT\&s1=\%22Bardell\%3B+Ron\%22.INNM.\&OS=IN/\%22Bardell;+Ron\%22\&RS=IN/\%22Bardell;+Ron\%22}, author = {Padmanabhan, Aravind and Rezachek, Tom and Bardell, Ron L.} } @patent {saltsman_united_2013, title = {United {States} {Patent}: 8557198 - {Microfluidic} devices for fluid manipulation and analysis}, number = {8557198}, year = {2013}, month = {oct}, abstract = {The present invention relates to microfluidic devices and methods for manipulating and analyzing fluid samples. The disclosed microfluidic devices utilize a plurality of microfluidic channels, inlets, valves, filter, pumps, liquid barriers and other elements arranged in various configurations to manipulate the flow of a fluid sample in order to prepare such sample for analysis.}, url = {http://patft.uspto.gov/netacgi/nph-Parser?Sect1=PTO2\&Sect2=HITOFF\&p=1\&u=\%2Fnetahtml\%2FPTO\%2Fsearch-bool.html\&r=4\&f=G\&l=50\&co1=AND\&d=PTXT\&s1=\%22Weigl\%3B+Bernhard\%22.INNM.\&OS=IN/\%22Weigl;+Bernhard\%22\&RS=IN/\%22Weigl;+Bernhard\%22}, author = {Saltsman, Patrick and Shen, Mingchao and Houkal, Jeffrey M. and Lancaster, Christy A. and Battrell, C. Frederick and Weigl, Bernhard H.} } @article {207, title = {Isothermal amplification using a chemical heating device for point-of-care detection of HIV-1.}, journal = {PLoS One}, volume = {7}, year = {2012}, month = {2012}, pages = {e31432}, abstract = {

BACKGROUND: To date, the use of traditional nucleic acid amplification tests (NAAT) for detection of HIV-1 DNA or RNA has been restricted to laboratory settings due to time, equipment, and technical expertise requirements. The availability of a rapid NAAT with applicability for resource-limited or point-of-care (POC) settings would fill a great need in HIV diagnostics, allowing for timely diagnosis or confirmation of infection status, as well as facilitating the diagnosis of acute infection, screening and evaluation of infants born to HIV-infected mothers. Isothermal amplification methods, such as reverse-transcription, loop-mediated isothermal amplification (RT-LAMP), exhibit characteristics that are ideal for POC settings, since they are typically quicker, easier to perform, and allow for integration into low-tech, portable heating devices.

METHODOLOGY/SIGNIFICANT FINDINGS: In this study, we evaluated the HIV-1 RT-LAMP assay using portable, non-instrumented nucleic acid amplification (NINA) heating devices that generate heat from the exothermic reaction of calcium oxide and water. The NINA heating devices exhibited stable temperatures throughout the amplification reaction and consistent amplification results between three separate devices and a thermalcycler. The performance of the NINA heaters was validated using whole blood specimens from HIV-1 infected patients.

CONCLUSION: The RT-LAMP isothermal amplification method used in conjunction with a chemical heating device provides a portable, rapid and robust NAAT platform that has the potential to facilitate HIV-1 testing in resource-limited settings and POC.

}, keywords = {AIDS Serodiagnosis, DNA Primers, DNA, Viral, Equipment Design, Heating, HIV Infections, HIV-1, Humans, Nucleic Acid Amplification Techniques, Point-of-Care Systems, RNA, Viral, Temperature}, issn = {1932-6203}, doi = {10.1371/journal.pone.0031432}, author = {Curtis, Kelly A and Rudolph, Donna L and Nejad, Irene and Singleton, Jered and Beddoe, Andy and Weigl, Bernhard and LaBarre, Paul and Owen, S Michele} } @patent {reed_united_2012, title = {United {States} {Patent}: 8163535 - {Devices} and processes for nucleic acid extraction}, number = {8163535}, year = {2012}, month = {apr}, abstract = {Devices, processes, and kits for the extraction of nucleic acids from biological samples are disclosed. The devices comprise a first port, a second port, and a binding chamber intermediate and in fluid communication with the first port and the second port. The binding chamber comprises an unmodified flat glass surface effective for binding a heterogeneous population of nucleic acids. The first port, second port, and binding chamber define a continuous fluid pathway that is essentially free of nucleic acid-specific binding sites.}, url = {http://patft.uspto.gov/netacgi/nph-Parser?Sect1=PTO2\&Sect2=HITOFF\&p=1\&u=\%2Fnetahtml\%2FPTO\%2Fsearch-bool.html\&r=1\&f=G\&l=50\&co1=AND\&d=PTXT\&s1=\%22Sharma\%3B+Nigel\%22.INNM.\&OS=IN/\%22Sharma;+Nigel\%22\&RS=IN/\%22Sharma;+Nigel\%22}, author = {Reed, Michael W. and Nanassy, Oliver Z. and Haydock, Paul V. and Sharma, Nigel Rudra and Bardell, Ronald L. and Hargrave, Perry} } @patent {padmanabhan_united_2012, title = {United {States} {Patent}: 8182767 - {Needle}-septum interface for a fluidic analyzer}, number = {8182767}, year = {2012}, month = {may}, abstract = {Instrument-cartridge interfaces for fluidic analyzers that have an instrument and a removable cartridge are disclosed. For example, and in one illustrative embodiment, the instrument may include a needle that is adapted to penetrate a septum on a removable cartridge. In another illustrative embodiment, the instrument may include a plunger that is adapted to deform a deformable membrane on a removable cartridge. In yet another illustrative embodiment, the instrument may include a nozzle that is adapted to mate and seal with a flow channel on a removable cartridge. Techniques for detecting the flow rate in a flow channel on a removable cartridge, as well as the position of fluid in a flow channel of a removable cartridge, are also disclosed.}, url = {http://patft.uspto.gov/netacgi/nph-Parser?Sect1=PTO2\&Sect2=HITOFF\&p=1\&u=\%2Fnetahtml\%2FPTO\%2Fsearch-bool.html\&r=13\&f=G\&l=50\&co1=AND\&d=PTXT\&s1=\%22Bardell\%3B+Ron\%22.INNM.\&OS=IN/\%22Bardell;+Ron\%22\&RS=IN/\%22Bardell;+Ron\%22}, author = {Padmanabhan, Aravind and Rezachek, Tom and Bardell, Ron L.} } @patent {padmanabhan_united_2012-1, title = {United {States} {Patent}: 8273294 - {Molded} cartridge with 3-{D} hydrodynamic focusing}, number = {8273294}, year = {2012}, month = {sep}, abstract = {A microfluidic circuit cartridge having 3-D hydrodynamic focusing. The cartridge may be fabricated with injection-molded or other molded layers providing a 3-D structure. A flow channel on the card may have a sample core flowing in a fluid of a flow channel for analysis. The sample core may be adjustable in position within the channel with one or more jets or channels of fluid being injected into the flow channel. The jets may also adjust the size of the sample core. There may be a hemoglobin measurement mechanism or card with a cuvette.}, url = {http://patft.uspto.gov/netacgi/nph-Parser?Sect1=PTO2\&Sect2=HITOFF\&p=1\&u=\%2Fnetahtml\%2FPTO\%2Fsearch-bool.html\&r=12\&f=G\&l=50\&co1=AND\&d=PTXT\&s1=\%22Bardell\%3B+Ron\%22.INNM.\&OS=IN/\%22Bardell;+Ron\%22\&RS=IN/\%22Bardell;+Ron\%22}, author = {Padmanabhan, Aravind and Bardell, Ron L.} } @patent {marsot_united_2012, title = {United {States} {Patent}: 8282576 - {Method} and apparatus for an improved sample capture device}, number = {8282576}, year = {2012}, abstract = {A body fluid sampling device is provided. A mesh may be used to guide blood or fluid to travel directly from the wound to an analyte detecting port on the cartridge. Thus the volume of blood or body fluid produced at the wound site irregardless of its droplet geometry can be reliable and substantially completely transported to the analyte detecting member for measurement.}, url = {http://patft.uspto.gov/netacgi/nph-Parser?Sect1=PTO2\&Sect2=HITOFF\&p=1\&u=\%2Fnetahtml\%2FPTO\%2Fsearch-bool.html\&r=11\&f=G\&l=50\&co1=AND\&d=PTXT\&s1=\%22Bardell\%3B+Ron\%22.INNM.\&OS=IN/\%22Bardell;+Ron\%22\&RS=IN/\%22Bardell;+Ron\%22}, author = {Marsot, Travis and Lum, Paul and Alden, Don and Ross, James and Bardell, Ron L. and Weigl, Bernhard} } @patent {saltsman_united_2012, title = {United {States} {Patent}: 8318109 - {Microfluidic} devices for fluid manipulation and analysis}, number = {8318109}, year = {2012}, month = {nov}, abstract = {The present invention relates to microfluidic devices and methods for manipulating and analyzing fluid samples. The disclosed microfluidic devices utilize a plurality of microfluidic channels, inlets, valves, filter, pumps, liquid barriers and other elements arranged in various configurations to manipulate the flow of a fluid sample in order to prepare such sample for analysis.}, url = {http://patft.uspto.gov/netacgi/nph-Parser?Sect1=PTO2\&Sect2=HITOFF\&p=1\&u=\%2Fnetahtml\%2FPTO\%2Fsearch-bool.html\&r=6\&f=G\&l=50\&co1=AND\&d=PTXT\&s1=\%22Weigl\%3B+Bernhard\%22.INNM.\&OS=IN/\%22Weigl;+Bernhard\%22\&RS=IN/\%22Weigl;+Bernhard\%22}, author = {Saltsman, Patrick and Shen, Mingchao and Houkal, Jeffrey M. and Lancaster, Christy A. and Battrell, C. Frederick and Weigl, Bernhard H.} } @patent {padmanabhan_united_2012-2, title = {United {States} {Patent}: 8323564 - {Portable} sample analyzer system}, number = {8323564}, year = {2012}, month = {dec}, abstract = {A system relating to sample analyzers, and more particular, to sample analyzers that are simple to operate and have a reduced risk of providing an erroneous result to a user. In some cases, the sample analyzer may be a portable sample analyzer that includes a disposable fluidic cartridge. The operators of the analyzers need not be trained.}, url = {http://patft.uspto.gov/netacgi/nph-Parser?Sect1=PTO2\&Sect2=HITOFF\&p=1\&u=\%2Fnetahtml\%2FPTO\%2Fsearch-bool.html\&r=10\&f=G\&l=50\&co1=AND\&d=PTXT\&s1=\%22Bardell\%3B+Ron\%22.INNM.\&OS=IN/\%22Bardell;+Ron\%22\&RS=IN/\%22Bardell;+Ron\%22}, author = {Padmanabhan, Aravind and Cox, James A. and Fritz, Bernard S. and Rezachek, Tom M. and Reutiman, Peter L. and Bardell, Ron L. and Cabuz, Cleopatra} } @article {206, title = {The Value of Clinical Needs Assessments for Point-of-Care Diagnostics.}, journal = {Point Care}, volume = {11}, year = {2012}, month = {2012 Jun}, pages = {108-113}, abstract = {

Most entrepreneurial ventures fail long before the core technology can be brought to the marketplace because of disconnects in performance and usability measures such as accuracy, cost, complexity, assay stability, and time requirements between technology developers{\textquoteright} specifications and needs of the end-users. By going through a clinical needs assessment (CNA) process, developers will gain vital information and a clear focus that will help minimize the risks associated with the development of new technologies available for use within the health care system. This article summarizes best practices of the principal investigators of the National Institute of Biomedical Imaging and Bioengineering point-of-care (POC) centers within the National Institute of Biomedical Imaging and Bioengineering POC Technologies Research Network. Clinical needs assessments are particularly important for product development areas that do not sufficiently benefit from traditional market research, such as grant-funded research and development, new product lines using cutting-edge technologies developed in start-up companies, and products developed through product development partnerships for low-resource settings. The objectives of this article were to (1) highlight the importance of CNAs for development of POC devices, (2) discuss methods applied by POC Technologies Research Network for assessing clinical needs, and (3) provide a road map for future CNAs.

}, issn = {1533-029X}, doi = {10.1097/POC.0b013e31825a241e}, author = {Weigl, Bernhard H and Gaydos, Charlotte A and Kost, Gerald and Beyette, Fred R and Sabourin, Stephanie and Rompalo, Anne and de Los Santos, Tala and McMullan, Jason T and Haller, John} } @article {211, title = {Association of elevated E6 oncoprotein with grade of cervical neoplasia using PDZ interaction-mediated precipitation of E6.}, journal = {J Low Genit Tract Dis}, volume = {15}, year = {2011}, month = {2011 Apr}, pages = {169-76}, abstract = {

OBJECTIVE: To determine the expression of human papillomavirus (HPV) type 16 E6 oncoprotein in cervical specimens of women with and without cervical intraepithelial neoplasia (CIN).

MATERIALS AND METHODS: Cervical specimens from 2,530 unscreened women aged 30 to 54 years from Shanxi, China, were obtained. All women were assessed by liquid-based cytology, high-risk HPV DNA tests, and colposcopy with directed biopsy and endocervical curettage as necessary. Women with abnormal cytologic results or positive HPV DNA results were recalled for colposcopy, 4-quadrant cervical biopsies, and endocervical curettage. Women with biopsy-proven CIN and cancer and a convenience sample of HC2-positive, disease-negative women were tested for the presence of HPV-16 infection via HPV-16 E6 DNA-specific polymerase chain reaction. A PDZ interaction-mediated E6 oncoprotein precipitation method followed by E6-specific Western blot was performed on specimens from women with HPV-16 infections. Associations between elevated expression of E6 oncoprotein and CIN 2 and 3 were determined using logistic regression and a reference category of CIN 1 and disease-negative.

RESULTS: A significant trend for the detection of HPV-16 E6 oncoprotein in specimen of women with proven HPV-16 infection was determined: 0\% (0/12), 12.5\% (1/8), 36.4\% (4/11), and 42.9\% (3/7) of those with negative findings, CIN 1, 2, and 3, respectively (p = .01). Compared with the category combining negative findings and CIN 1, detection of E6 oncoprotein was associated with CIN 2 (odds ratio = 10.9, p = .05) and CIN 3 (odds ratio = 14.3, p = .04).

CONCLUSIONS: There is a significant association between elevated expression of E6 oncoprotein and grade of CIN. This finding seems consistent with the role played by E6 oncoprotein in carcinogenesis.

}, keywords = {Adult, Blotting, Western, Cervical Intraepithelial Neoplasia, Cervix Uteri, China, Female, Human papillomavirus 16, Humans, Immunoprecipitation, Middle Aged, Oncogene Proteins, Viral, Papillomavirus Infections, Repressor Proteins, Up-Regulation, Uterine Cervical Neoplasms}, issn = {1526-0976}, doi = {10.1097/LGT.0b013e3181f6c84d}, author = {Sellors, John W and Schweizer, Johannes G and Lu, Peter S and Liu, Bin and Weigl, Bernhard H and Cui, Jian Feng and Peck, Roger B and Lewis, Kristen and Lim, Jeanette and Howard, Michelle and Mahoney, Charles W and McAllister, Linda and Berard-Bergery, Marthe and Bry, Claire and Labiad, Yassine A and Li, Haimin and Liu, Lilyn and Silver, Jon and Chen, Wen and Qiao, You Lin} } @article {208, title = {Gestational diabetes screening: the low-cost algorithm.}, journal = {Int J Gynaecol Obstet}, volume = {115 Suppl 1}, year = {2011}, month = {2011 Nov}, pages = {S30-3}, abstract = {

The American Diabetes Association has endorsed the demanding recommendation by the International Association of the Diabetes and Pregnancy Study Groups (IADPSG) that every pregnant woman should undergo the oral glucose tolerance test (OGTT) for the screening of gestational diabetes mellitus (GDM). The aim of this study was to find out if the fasting plasma glucose (FPG) and newer emerging technologies could simplify the cumbersome IADPSG algorithm. Two FPG thresholds (of the OGTT) were used to rule in and rule out GDM in the Hyperglycemia and Adverse Pregnancy Outcome (HAPO) cohort (n = 23316) and a population at high risk for GDM (n = 10283). For the HAPO cohort and the high-risk population, respectively, FPG thresholds of: (a) >= 5.1 mmol/L (specificity 100\%) independently ruled in GDM in 1769 (8.3\%) women and 2975 (28.9\%) women; and (b) <= 4.4 mmol/L ruled out GDM in 11526 (49.4\%) women (84.1\% sensitivity) and 2228 (21.7\%) women (95.4\% sensitivity). Use of the FPG independently could have avoided 13295 (57.0\%) and 5203 (50.6\%) OGTTs in the 2 groups. The initial FPG-by significantly reducing the number of cumbersome OGTTs needed-can make the IADPSG recommendations more acceptable worldwide. The number of GDM women missed is population dependent. For low-resource countries, alternative newer and cheaper tests in development hold an exciting future.

}, keywords = {Algorithms, Diabetes, Gestational, Fasting, Female, Glucose Tolerance Test, Guidelines as Topic, Humans, Hyperglycemia, Mass Screening, Pregnancy, Pregnancy Complications, Sensitivity and Specificity}, issn = {1879-3479}, doi = {10.1016/S0020-7292(11)60009-X}, author = {Agarwal, Mukesh M and Weigl, Bernhard and Hod, Moshe} } @article {212, title = {A highly sensitive rapid diagnostic test for Chagas disease that utilizes a recombinant Trypanosoma cruzi antigen.}, journal = {IEEE Trans Biomed Eng}, volume = {58}, year = {2011}, month = {2011 Mar}, pages = {814-7}, abstract = {

Improved diagnostic tests for Chagas disease are urgently needed. A new lateral flow rapid test for Chagas disease is under development at PATH, in collaboration with Laboratorio Lemos of Argentina, which utilizes a recombinant antigen for detection of antibodies to Trypanosoma cruzi. To evaluate the performance of this test, 375 earlier characterized serum specimens from a region where Chagas is endemic were tested using a reference test (the Ortho T. cruzi ELISA, Johnson \& Johnson), a commercially available rapid test (Chagas STAT-PAK, Chembio), and the PATH-Lemos rapid test. Compared to the composite reference tests, the PATH-Lemos rapid test demonstrated an optimal sensitivity of 99.5\% and specificity of 96.8\%, while the Chagas STAT-PAK demonstrated a sensitivity of 95.3\% and specificity of 99.5\%. These results indicate that the PATH-Lemos rapid test shows promise as an improved and reliable tool for screening and diagnosis of Chagas disease.

}, keywords = {Antibodies, Protozoan, Antigens, Protozoan, Chagas Disease, Humans, Immunoassay, Point-of-Care Systems, Recombinant Proteins, Sensitivity and Specificity, Trypanosoma cruzi}, issn = {1558-2531}, doi = {10.1109/TBME.2010.2087334}, author = {Barfield, C A and Barney, R S and Crudder, C H and Wilmoth, J L and Stevens, D S and Mora-Garcia, S and Yanovsky, M J and Weigl, B H and Yanovsky, J} } @article {210, title = {Instrument-free nucleic acid amplification assays for global health settings.}, journal = {Proc SPIE Int Soc Opt Eng}, volume = {8029}, year = {2011}, month = {2011 May 16}, abstract = {

Many infectious diseases that affect global health are most accurately diagnosed through nucleic acid amplification and detection. However, existing nucleic acid amplification tests are too expensive and complex for most low-resource settings. The small numbers of centralized laboratories that exist in developing countries tend to be in urban areas and primarily cater to the affluent. In contrast, rural area health care facilities commonly have only basic equipment and health workers have limited training and little ability to maintain equipment and handle reagents.(1) Reliable electric power is a common infrastructure shortfall. In this paper, we discuss a practical approach to the design and development of non-instrumented molecular diagnostic tests that exploit the benefits of isothermal amplification strategies. We identify modular instrument-free technologies for sample collection, sample preparation, amplification, heating, and detection. By appropriately selecting and integrating these instrument-free modules, we envision development of an easy to use, infrastructure independent diagnostic test that will enable increased use of highly accurate molecular diagnostics at the point of care in low-resource settings.

}, issn = {0277-786X}, doi = {10.1117/12.882868}, author = {LaBarre, Paul and Boyle, David and Hawkins, Kenneth and Weigl, Bernhard} } @article {214, title = {Non-Instrumented Nucleic Acid Amplification (NINA) for Rapid Detection of Ralstonia solanacearum Race 3 Biovar 2.}, journal = {Biol Eng Trans}, volume = {4}, year = {2011}, month = {2011}, pages = {69-80}, abstract = {

We report on the use of a non-instrumented device for the implementation of a loop-mediated amplification (LAMP) based assay for the select-agent bacterial-wilt pathogen Ralstonia solanacearum race 3 biovar 2. Heat energy is generated within the device by the exothermic hydration of calcium oxide, and the reaction temperature is regulated by storing latent energy at the melting temperature of a renewable lipid-based engineered phase-change material. Endpoint detection of the LAMP reaction is achieved without opening the reaction tube by observing the fluorescence of an innovative FRET-based hybridization probe with a simple custom fluorometer. Non-instrumented devices could maintain reactions near the design temperature of 63{\textdegree}C for at least an hour. Using this approach DNA extracted from the pathogen could be detected at fewer than ten copies within a 25 μL reaction mix, illustrating the potential of these technologies for simple, powerful agricultural diagnostics in the field. Furthermore, the assay was just as reliable when implemented in a tropical environment at 31{\textdegree}C as it was when implemented in an air-conditioned lab maintained at 22{\textdegree}C, illustrating the potential value of the technology for field conditions in the tropics and subtropics.

}, issn = {2162-643X}, doi = {10.13031/2013.38508}, author = {Kubota, Ryo and LaBarre, Paul and Singleton, Jered and Beddoe, Andy and Weigl, Bernhard H and Alvarez, Anne M and Jenkins, Daniel M} } @article {213, title = {Point-of-Care Technologies for Health Care.}, journal = {IEEE Trans Biomed Eng}, volume = {58}, year = {2011}, month = {2011 Mar}, pages = {732-5}, keywords = {Diagnosis, Computer-Assisted, Humans, Monitoring, Physiologic, Point-of-Care Systems}, issn = {1558-2531}, doi = {10.1109/TBME.2011.2109251}, author = {Beyette, Fred R and Gaydos, Charlotte A and Kost, Gerald J and Weigl, Bernhard H} } @article {209, title = {A simple, inexpensive device for nucleic acid amplification without electricity-toward instrument-free molecular diagnostics in low-resource settings.}, journal = {PLoS One}, volume = {6}, year = {2011}, month = {2011}, pages = {e19738}, abstract = {

BACKGROUND: Molecular assays targeted to nucleic acid (NA) markers are becoming increasingly important to medical diagnostics. However, these are typically confined to wealthy, developed countries; or, to the national reference laboratories of developing-world countries. There are many infectious diseases that are endemic in low-resource settings (LRS) where the lack of simple, instrument-free, NA diagnostic tests is a critical barrier to timely treatment. One of the primary barriers to the practicality and availability of NA assays in LRS has been the complexity and power requirements of polymerase chain reaction (PCR) instrumentation (another is sample preparation).

METHODOLOGY/PRINCIPAL FINDINGS: In this article, we investigate the hypothesis that an electricity-free heater based on exothermic chemical reactions and engineered phase change materials can successfully incubate isothermal NA amplification assays. We assess the heater{\textquoteright}s equivalence to commercially available PCR instruments through the characterization of the temperature profiles produced, and a minimal method comparison. Versions of the prototype for several different isothermal techniques are presented.

CONCLUSIONS/SIGNIFICANCE: We demonstrate that an electricity-free heater based on exothermic chemical reactions and engineered phase change materials can successfully incubate isothermal NA amplification assays, and that the results of those assays are not significantly different from ones incubated in parallel in commercially available PCR instruments. These results clearly suggest the potential of the non-instrumented nucleic acid amplification (NINA) heater for molecular diagnostics in LRS. When combined with other innovations in development that eliminate power requirements for sample preparation, cold reagent storage, and readout, the NINA heater will comprise part of a kit that should enable electricity-free NA testing for many important analytes.

}, keywords = {Developing Countries, Electricity, Hot Temperature, Molecular Diagnostic Techniques, Nucleic Acid Amplification Techniques, Plasmodium falciparum, Reference Standards}, issn = {1932-6203}, doi = {10.1371/journal.pone.0019738}, author = {LaBarre, Paul and Hawkins, Kenneth R and Gerlach, Jay and Wilmoth, Jared and Beddoe, Andrew and Singleton, Jered and Boyle, David and Weigl, Bernhard} } @patent {cox_united_2011, title = {United {States} {Patent}: 8034296 - {Microfluidic} card for {RBC} analysis}, number = {8034296}, year = {2011}, month = {oct}, abstract = {A microfluidic circuit cartridge for a complete blood count, including analyses of red blood cells. Various parameters of the red blood cells may be attained. The cartridge may have sphering mechanism which has a channel or loop with a configuration for reducing or eliminating cell settling. The channel or loop may incorporate a combination of straight and curve paths in the context of gravity. The channel may alternatively have a hydrophilic or hydrophobic inside surface. Again alternatively, the channel may have an electro-wettable inside surface. Or, the channel may be subject to an electric or magnetic field. There may also be a mechanism for reducing or eliminating clumping of a sample.}, url = {http://patft.uspto.gov/netacgi/nph-Parser?Sect1=PTO2\&Sect2=HITOFF\&p=1\&u=\%2Fnetahtml\%2FPTO\%2Fsearch-bool.html\&r=14\&f=G\&l=50\&co1=AND\&d=PTXT\&s1=\%22Bardell\%3B+Ron\%22.INNM.\&OS=IN/\%22Bardell;+Ron\%22\&RS=IN/\%22Bardell;+Ron\%22}, author = {Cox, James A. and Padmanabhan, Aravind and Bardell, Ron L. and Zins, Christopher J.} } @article {216, title = {Laboratory operations, specimen processing, and handling for viral load testing and surveillance.}, journal = {J Infect Dis}, volume = {201 Suppl 1}, year = {2010}, month = {2010 Apr 15}, pages = {S27-36}, abstract = {

RNA remains the most informative and accurate biomarker for human immunodeficiency virus type 1 load diagnostics and for surveillance of drug resistance markers. Viral load testing by nucleic acid amplification currently is a complex and expensive test that is restricted to centralized laboratory testing. Successful extension of centralized viral load testing to rural or remote settings is a major challenge. Emerging nucleic acid-based technologies are progressing rapidly toward platforms appropriate for field use in low-resource settings, leaving a growing gap for sample processing technologies that complement them. One area in which new technologies could be applied to improve access is clinical specimen preservation and processing. Novel technologies that extract nucleic acid from clinical specimens and stabilize it at the point of specimen collection could fill this gap. In addition, these technologies may provide alternative viral load detection and surveillance solutions to the current centralized laboratory testing paradigm.

}, keywords = {HIV, HIV Infections, Humans, RNA, Viral, Specimen Handling, Viral Load}, issn = {1537-6613}, doi = {10.1086/650390}, author = {Puren, Adrian and Gerlach, Jay L and Weigl, Bernhard H and Kelso, David M and Domingo, Gonzalo J} } @article {215, title = {Non-instrumented nucleic acid amplification (NINA): instrument-free molecular malaria diagnostics for low-resource settings.}, journal = {Conf Proc IEEE Eng Med Biol Soc}, volume = {2010}, year = {2010}, month = {2010}, pages = {1097-9}, abstract = {

We have achieved the first complete, non-instrumented nucleic acid amplification test (NAAT) using a calcium oxide heat source thermally linked to an engineered phase change material. These two components alone maintain a thermal profile suitable for the loop-mediated isothermal amplification assay. Starting with computational fluid dynamics analysis, we identified nominal geometry for the exothermic reaction chamber, phase change material chamber, thermal insulation, and packaging. Using this model, we designed and fabricated an alpha prototype assay platform. We have verified the function of this multi-pathogen-capable platform with both fluorescent and visual turbidity indications using samples spiked with malaria DNA. Both the exothermically heated platform samples and samples heated on a Perkin-Elmer GeneAmp9600 thermocycler were first incubated at 62{\textdegree}C for 45 minutes, then heated to 95{\textdegree}C to terminate enzyme activity, then analyzed. Results from the exothermically heated, non-instrumented platform were comparable to those from the thermocycler. These developments will enable point-of-care diagnostics using accurate NAATs which until now have required a well-equipped laboratory. The aim of this research is to provide pathogen detection with NAAT-level sensitivity in low-resource settings where assays such as immunochromatographic strip tests are successfully used but where there is no access to the infrastructure and logistics required to operate and maintain instrument-based diagnostics.

}, keywords = {DNA, Protozoan, Heating, Humans, Malaria, Falciparum, Molecular Diagnostic Techniques, Nucleic Acid Amplification Techniques}, issn = {1557-170X}, doi = {10.1109/IEMBS.2010.5627346}, author = {LaBarre, Paul and Gerlach, Jay and Wilmoth, Jared and Beddoe, Andrew and Singleton, Jered and Weigl, Bernhard} } @patent {breidford_united_2010, title = {United {States} {Patent}: 7648835 - {System} and method for heating, cooling and heat cycling on microfluidic device}, number = {7648835}, year = {2010}, month = {jan}, abstract = {An integrated heat exchange system on a microfluidic card. According to one aspect of the invention, the portable microfluidic card has a heating, cooling and heat cycling system on-board such that the card can be used portably. The microfluidic card includes one or more reservoirs containing exothermic or endothermic material. Once the chemical process of the reservoir material is activated, the reservoir provides heat or cooling to specific locations of the microfluidic card. Multiple reservoirs may be included on a single card to provide varying temperatures. The assay chemicals can be moved to the various reservoirs to create a thermal cycle useful in many biological reactions, for example, Polymerase Chain Reaction (PCR) or rtPCR. According to another aspect of the invention, the integrated heat exchanger is an adjacent microfluidic circuit containing fluid that is either independently heated or cooled, or is an exothermic or endothermic material, such that the fluid in the adjacent circuit imparts a change in temperature to the assay fluid in an independent circuit. According to yet another aspect of the invention, a thermal electric cooler (TEC) is used for thermocycling the amplification chamber of a disposable microfluidic card.}, url = {http://patft.uspto.gov/netacgi/nph-Parser?Sect1=PTO2\&Sect2=HITOFF\&p=1\&u=\%2Fnetahtml\%2FPTO\%2Fsearch-bool.html\&r=9\&f=G\&l=50\&co1=AND\&d=PTXT\&s1=\%22Weigl\%3B+Bernhard\%22.INNM.\&OS=IN/\%22Weigl;+Bernhard\%22\&RS=IN/\%22Weigl;+Bernhard\%22}, author = {Breidford, Wayne L. and Lancaster, Christy A. and Hayenga, Jon W. and Bardell, Ronald L. and Tonn, Jeffrey F. and Weigl, Bernhard H.} } @article {217, title = {Simplicity of use: a critical feature for widespread adoption of diagnostic technologies in low-resource settings.}, journal = {Expert Rev Med Devices}, volume = {6}, year = {2009}, month = {2009 Sep}, pages = {461-4}, keywords = {Biotechnology, Diagnostic Imaging, Human Engineering, Internationality, Quality Assurance, Health Care}, issn = {1745-2422}, doi = {10.1586/erd.09.31}, author = {Weigl, B H and Boyle, D S and de los Santos, T and Peck, R B and Steele, M S} } @patent {padmanabhan_united_2009, title = {United {States} {Patent}: 7485153 - {Fluid} free interface for a fluidic analyzer}, number = {7485153}, year = {2009}, month = {feb}, abstract = {Instrument-cartridge interfaces for fluidic analyzers that have an instrument and a removable cartridge are disclosed. For example, and in one illustrative embodiment, the instrument may include a needle that is adapted to penetrate a septum on a removable cartridge. In another illustrative embodiment, the instrument may include a plunger that is adapted to deform a deformable membrane on a removable cartridge. In yet another illustrative embodiment, the instrument may include a nozzle that is adapted to mate and seal with a flow channel on a removable cartridge. Techniques for detecting the flow rate in a flow channel on a removable cartridge, as well as the position of fluid in a flow channel of a removable cartridge, are also disclosed.}, url = {http://patft.uspto.gov/netacgi/nph-Parser?Sect1=PTO2\&Sect2=HITOFF\&p=1\&u=\%2Fnetahtml\%2FPTO\%2Fsearch-bool.html\&r=15\&f=G\&l=50\&co1=AND\&d=PTXT\&s1=\%22Bardell\%3B+Ron\%22.INNM.\&OS=IN/\%22Bardell;+Ron\%22\&RS=IN/\%22Bardell;+Ron\%22}, author = {Padmanabhan, Aravind and Rezachek, Tom and Bardell, Ron L. and Bird, Douglas and Fritz, Bernard S.} } @patent {breidford_united_2009, title = {United {States} {Patent}: 7544506 - {System} and method for heating, cooling and heat cycling on microfluidic device}, number = {7544506}, year = {2009}, month = {jun}, abstract = {An integrated heat exchange system on a microfluidic card. According to one aspect of the invention, the portable microfluidic card has a heating, cooling and heat cycling system on-board such that the card can be used portably. The microfluidic card includes one or more reservoirs containing exothermic or endothermic material. Once the chemical process of the reservoir material is activated, the reservoir provides heat or cooling to specific locations of the microfluidic card. Multiple reservoirs may be included on a single card to provide varying temperatures. The assay chemicals can be moved to the various reservoirs to create a thermal cycle useful in many biological reactions, for example, Polymerase Chain Reaction (PCR) or rtPCR. According to another aspect of the invention, the integrated heat exchanger is an adjacent microfluidic circuit containing fluid that is either independently heated or cooled, or is an exothermic or endothermic material, such that the fluid in the adjacent circuit imparts a change in temperature to the assay fluid in an independent circuit. According to yet another aspect of the invention, a thermal electric cooler (TEC) is used for thermocycling the amplification chamber of a disposable microfluidic card.}, url = {http://patft.uspto.gov/netacgi/nph-Parser?Sect1=PTO2\&Sect2=HITOFF\&p=1\&u=\%2Fnetahtml\%2FPTO\%2Fsearch-bool.html\&r=11\&f=G\&l=50\&co1=AND\&d=PTXT\&s1=\%22Weigl\%3B+Bernhard\%22.INNM.\&OS=IN/\%22Weigl;+Bernhard\%22\&RS=IN/\%22Weigl;+Bernhard\%22}, author = {Breidford, Wayne and Lancaster, Christy A. and Hayenga, Jon Wallace and Bardell, Ronald L. and Tonn, Jeffrey F. and Weigl, Bernhard H.} } @patent {reed_united_2009, title = {United {States} {Patent}: 7608399 - {Device} and method for extraction and analysis of nucleic acids from biological samples}, number = {7608399}, year = {2009}, month = {oct}, abstract = {Device and methods for extracting and analyzing nucleic acids from biological samples.}, url = {http://patft.uspto.gov/netacgi/nph-Parser?Sect1=PTO2\&Sect2=HITOFF\&p=1\&u=\%2Fnetahtml\%2FPTO\%2Fsearch-bool.html\&r=2\&f=G\&l=50\&co1=AND\&d=PTXT\&s1=\%22Sharma\%3B+Nigel\%22.INNM.\&OS=IN/\%22Sharma;+Nigel\%22\&RS=IN/\%22Sharma;+Nigel\%22}, author = {Reed, Michael W. and Nanassy, Oliver Z. and Haydock, Paul V. and Sharma, Nigel Rudra and Bardell, Ronald L. and Hargrave, Perry} } @article {219, title = {A new HPV-DNA test for cervical-cancer screening in developing regions: a cross-sectional study of clinical accuracy in rural China.}, journal = {Lancet Oncol}, volume = {9}, year = {2008}, month = {2008 Oct}, pages = {929-36}, abstract = {

BACKGROUND: A new test (careHPV; QIAGEN, Gaithersburg, MD, USA) has been developed to detect 14 high-risk types of carcinogenic human papillomavirus (HPV) in about 2.5 h, to screen women in developing regions for cervical intraepithelial neoplasia (CIN). We did a cross-sectional study to assess the clinical accuracy of careHPV as a rapid screening test in two county hospitals in rural China.

METHODS: From May 10 to June 15, 2007, the careHPV test was done locally by use of self-obtained vaginal and provider-obtained cervical specimens from a screening population-based set of 2530 women aged 30 to 54 years in Shanxi province, China. All women were assessed by visual inspection with acetic acid (VIA), Digene High-Risk HPV HC2 DNA Test (HC2), liquid-based cytology, and colposcopy with directed biopsy and endocervical curettage as necessary. In 2388 women with complete data, 441 women with negative colposcopy, but unsatisfactory or abnormal cytology or who were positive on HC2 or the new careHPV test, were recalled for a second colposcopy, four-quadrant cervical biopsies, and endocervical curettage. An absence of independence between the tests was not adjusted for and the Bonferroni correction was used for multiple comparisons.

FINDINGS: Complete data were available for 2388 (94.4\%) women. 70 women had CIN2+ (moderate or severe CIN or cancer), of whom 23 had CIN3+. By use of CIN2+ as the reference standard and area-under-the-curve analysis with a two-sided alpha error level of 0.0083, the sensitivities and specificities of the careHPV test for a cut-off ratio cut-point of 0.5 relative light units, were 90.0\% (95\% CI 83.0-97.0) and 84.2\% (82.7-85.7), respectively, on cervical specimens, and 81.4\% (72.3-90.5) and 82.4\% (80.8-83.9), respectively, on vaginal specimens (areas under the curve not significantly different, p=0.0596), compared with 41.4\% (29.9-53.0) and 94.5\% (93.6-95.4) for VIA (areas under the curve significantly different, p=0.0001 and p=0.0031, for cervical and vaginal-specimen comparisons for the careHPV test, respectively). The sensitivity and specificity of HC2 for cervical specimens were 97.1\% (93.2-100) and 85.6\% (84.2-87.1), respectively (areas under the curve not significantly different from the careHPV test on cervical specimens, p=0.0163).

INTERPRETATION: The careHPV test is promising as a primary screening method for cervical-cancer prevention in low-resource regions.

}, keywords = {Adult, Alphapapillomavirus, Cervical Intraepithelial Neoplasia, China, Cross-Sectional Studies, DNA, Viral, Female, Humans, Mass Screening, Middle Aged, Papillomavirus Infections, Predictive Value of Tests, ROC Curve, Rural Health Services, Sensitivity and Specificity, Tumor Markers, Biological, Uterine Cervical Neoplasms}, issn = {1474-5488}, doi = {10.1016/S1470-2045(08)70210-9}, author = {Qiao, You-Lin and Sellors, John W and Eder, Paul S and Bao, Yan-Ping and Lim, Jeanette M and Zhao, Fang-Hui and Weigl, Bernhard and Zhang, Wen-Hua and Peck, Roger B and Li, Ling and Chen, Feng and Pan, Qing-Jing and Lorincz, Attila T} } @article {220, title = {The NIBIB Point of Care Technologies Research Network Center Themes and Opportunities for Exploratory POC Projects.}, journal = {Point Care}, volume = {7}, year = {2008}, month = {2008 Mar}, pages = {1-41}, abstract = {

This article describes the new National Institute of Biomedical Imaging and Bioengineering Point-of-Care (POC) Technologies Research Network and its 4 Centers. The goal is to build expertise in development of integrated systems that address unmet POC testing clinical needs. Centers will work individually and also collectively as part of the national network to coordinate development, clinical evaluation, and reduction to practice of new POC devices.

}, issn = {1533-029X}, doi = {10.1097/POC.0b013e318162f3dd}, author = {Kost, Gerald J and Korte, Brenda and Beyette, Fred R and Gaydos, Charlotte and Weigl, Bernhard} } @article {218, title = {Towards non- and minimally instrumented, microfluidics-based diagnostic devices.}, journal = {Lab Chip}, volume = {8}, year = {2008}, month = {2008 Dec}, pages = {1999-2014}, abstract = {

In many health care settings, it is uneconomical, impractical, or unaffordable to maintain and access a fully equipped diagnostics laboratory. Examples include home health care, developing-country health care, and emergency situations in which first responders are dealing with pandemics or biowarfare agent release. In those settings, fully disposable diagnostic devices that require no instrument support, reagent, or significant training are well suited. Although the only such technology to have found widespread adoption so far is the immunochromatographic rapid assay strip test, microfluidics holds promise to expand the range of assay technologies that can be performed in formats similar to that of a strip test. In this paper, we review progress toward development of disposable, low-cost, easy-to-use microfluidics-based diagnostics that require no instrument at all. We also present examples of microfluidic functional elements--including mixers, separators, and detectors--as well as complete microfluidic devices that function entirely without any moving parts and external power sources.

}, keywords = {Diagnostic Techniques and Procedures, Disposable Equipment, Microfluidics}, issn = {1473-0197}, doi = {10.1039/b811314a}, author = {Weigl, Bernhard and Domingo, Gonzalo and LaBarre, Paul and Gerlach, Jay} } @patent {battrell_united_2008, title = {United {States} {Patent}: 7416892 - {Method} and system for microfluidic manipulation, amplification and analysis of fluids, for example, bacteria assays and antiglobulin testing}, number = {7416892}, year = {2008}, month = {aug}, abstract = {A microfluidic system for isolation and amplification of DNA or RNA from aqueous solutions and detection of the DNA or RNA on a lateral flow detection strip, including a disposable microfluidic card for use in analysis of bacteria in platelets and an analysis of sexually transmitted diseases (STD) in urine. The card will include an embedded membrane that filters out cells and cellular debris. Any biological debris on the membrane will be lysed and the DNA or RNA amplified via PCR amplification protocol, including appropriate reagents and thermal cycling conditions. The amplified DNA or RNA are transferred to a lateral flow detection strip for a visual diagnostic read out. An alternate embodiment includes a microfluidic card for use in typing antiglobulin assays.}, url = {http://patft.uspto.gov/netacgi/nph-Parser?Sect1=PTO2\&Sect2=HITOFF\&p=1\&u=\%2Fnetahtml\%2FPTO\%2Fsearch-bool.html\&r=13\&f=G\&l=50\&co1=AND\&d=PTXT\&s1=\%22Weigl\%3B+Bernhard\%22.INNM.\&OS=IN/\%22Weigl;+Bernhard\%22\&RS=IN/\%22Weigl;+Bernhard\%22}, author = {Battrell, C. Frederick and Shen, Mingchao and Weigl, Bernhard H. and Houkal, Jeffrey M. and Lancaster, Christy A. and Breidford, Wayne} } @patent {saltsman_united_2008, title = {United {States} {Patent}: 7419638 - {Microfluidic} devices for fluid manipulation and analysis}, number = {7419638}, year = {2008}, month = {sep}, abstract = {The present invention relates to microfluidic devices and methods for manipulating and analyzing fluid samples. The disclosed microfluidic devices utilize a plurality of microfluidic channels, inlets, valves, filter, pumps, liquid barriers and other elements arranged in various configurations to manipulate the flow of a fluid sample in order to prepare such sample for analysis.}, url = {http://patft.uspto.gov/netacgi/nph-Parser?Sect1=PTO2\&Sect2=HITOFF\&p=1\&u=\%2Fnetahtml\%2FPTO\%2Fsearch-bool.html\&r=12\&f=G\&l=50\&co1=AND\&d=PTXT\&s1=\%22Weigl\%3B+Bernhard\%22.INNM.\&OS=IN/\%22Weigl;+Bernhard\%22\&RS=IN/\%22Weigl;+Bernhard\%22}, author = {Saltsman, Patrick and Shen, Mingchao and Houkal, Jeffrey M. and Lancaster, Christy A. and Battrell, C. Frederick and Weigl, Bernhard H.} } @patent {weigl_united_2007, title = {United {States} {Patent}: 7196842 - {Attenuating} filter for ultraviolet light}, number = {7196842}, year = {2007}, abstract = {An attenuating filter provides a prescribed attenuation of the intensity of transmitted, short-wavelength, ultraviolet light, in particular, at wavelengths below 200 nm, that is governed by a predefinable spatial distribution of its spectral transmittance. The filter has a transparent substrate (3), e.g. fabricated from crystalline calcium fluoride. A filter coating (5) fabricated from a dielectric material that absorbs over a predefined wavelength range is applied to at least one surface (4) of the substrate. In the case of operating wavelengths of about 193 nm, the filter coating consists largely of tantalum pentoxide. Filters of the type, which may be inexpensively fabricated with high yields, are noted for their high abilities to withstand laser radiation and may be effectively antireflection coated employing simply designed antireflection coatings.}, url = {http://patft.uspto.gov/netacgi/nph-Parser?Sect1=PTO2\&Sect2=HITOFF\&p=1\&u=\%2Fnetahtml\%2FPTO\%2Fsearch-bool.html\&r=16\&f=G\&l=50\&co1=AND\&d=PTXT\&s1=\%22Weigl\%3B+Bernhard\%22.INNM.\&OS=IN/\%22Weigl;+Bernhard\%22\&RS=IN/\%22Weigl;+Bernhard\%22}, author = {Weigl, Bernhard and DE and Paul, Hans-Jochen and DE and Eva, Eric and DE} } @patent {hayenga_united_2007, title = {United {States} {Patent}: 7223371 - {Microfluidic} channel network device}, number = {7223371}, year = {2007}, month = {may}, abstract = {Described herein is microfluidic device for joining fluids and a related method for doing the same. The device according to the present invention includes a microfluidic junction, an outlet channel, and a plurality of circuit units. A microfluidic junction is an area for converging multiple fluids. An outlet channel is capable of receiving fluid from the microfluidic junction. An outlet channel includes a first end connected with the microfluidic junction, a second end connected with a waste reservoir, and an analysis region positioned between the first end and the second end of the outlet channel. The device also includes a plurality of circuit units. Each circuit unit includes a source channel with a first end capable of receiving sample fluid and a second end connected with the microfluidic junction; a branch channel connected with the source channel at an intersection; and a flow diversion system capable of differentially directing fluid flowing through a source channel either into the microfluidic junction or into a branch channel.}, url = {http://patft.uspto.gov/netacgi/nph-Parser?Sect1=PTO2\&Sect2=HITOFF\&p=1\&u=\%2Fnetahtml\%2FPTO\%2Fsearch-bool.html\&r=15\&f=G\&l=50\&co1=AND\&d=PTXT\&s1=\%22Weigl\%3B+Bernhard\%22.INNM.\&OS=IN/\%22Weigl;+Bernhard\%22\&RS=IN/\%22Weigl;+Bernhard\%22}, author = {Hayenga, Jon W. and Weigl, Bernhard H. and Bardell, Ronald L. and Morris, Christopher J.} } @patent {weigl_united_2007-1, title = {United {States} {Patent}: 7271007 - {Microscale} diffusion immunoassay}, number = {7271007}, year = {2007}, abstract = {Methods and apparatuses are provided for determining presence and concentration of analytes by exploiting molecular binding reactions and differential diffusion rates. Analyte particles and binding particles are allowed to diffuse toward each other, and slowing of the diffusion front is detected when they meet. From the position of the diffusion front, presence and concentration of analyte particles can be determined. One embodiment provides a competitive immunoassay in a microfluidic format. This diffusion immunoassay (DIA) relies on measuring the concentration of labeled antigen along one dimension of a microchannel after allowing it to diffuse for a short time into a region containing specific antibodies. A simple microfluidic device, the T-Sensor, was used to implement a DIA to measure the concentration of phenytoin, a small drug molecule. Concentrations of analyte over the range of 50 to 1600 nM can be measured in less than a minute. The assay is homogeneous, rapid, requires only microliter volumes of reagents and sample, and is applicable to a wide range of analytes, including therapeutic drugs, molecular biological markers, and environmental contaminants. Methods for separating particles of similar size in a diffusion separator are also provided.}, url = {http://patft.uspto.gov/netacgi/nph-Parser?Sect1=PTO2\&Sect2=HITOFF\&p=1\&u=\%2Fnetahtml\%2FPTO\%2Fsearch-bool.html\&r=14\&f=G\&l=50\&co1=AND\&d=PTXT\&s1=\%22Weigl\%3B+Bernhard\%22.INNM.\&OS=IN/\%22Weigl;+Bernhard\%22\&RS=IN/\%22Weigl;+Bernhard\%22}, author = {Weigl, Bernhard H. and Yager, Paul and Kamholz, Andrew and Hatch, Anson} } @article {221, title = {A magnetic immunochromatographic strip test for detection of human papillomavirus 16 E6.}, journal = {Clin Chem}, volume = {52}, year = {2006}, month = {2006 Nov}, pages = {2170-2}, keywords = {Antibodies, Monoclonal, Chromatography, Enzyme-Linked Immunosorbent Assay, Female, Human papillomavirus 16, Humans, Magnetics, Oncogene Proteins, Viral, PDZ Domains, Protein Binding, Protein Interaction Mapping, Recombinant Fusion Proteins, Repressor Proteins, Sensitivity and Specificity}, issn = {0009-9147}, author = {Peck, Roger B and Schweizer, Johannes and Weigl, Bernhard H and Somoza, Chamorro and Silver, John and Sellors, John W and Lu, Peter S} } @article {222, title = {Microfluidic diagnostic technologies for global public health.}, journal = {Nature}, volume = {442}, year = {2006}, month = {2006 Jul 27}, pages = {412-8}, abstract = {

The developing world does not have access to many of the best medical diagnostic technologies; they were designed for air-conditioned laboratories, refrigerated storage of chemicals, a constant supply of calibrators and reagents, stable electrical power, highly trained personnel and rapid transportation of samples. Microfluidic systems allow miniaturization and integration of complex functions, which could move sophisticated diagnostic tools out of the developed-world laboratory. These systems must be inexpensive, but also accurate, reliable, rugged and well suited to the medical and social contexts of the developing world.

}, keywords = {Developing Countries, Diagnostic Tests, Routine, Humans, Internationality, Microfluidics, Public Health}, issn = {1476-4687}, doi = {10.1038/nature05064}, author = {Yager, Paul and Edwards, Thayne and Fu, Elain and Helton, Kristen and Nelson, Kjell and Tam, Milton R and Weigl, Bernhard H} } @patent {weigl_united_2006, title = {United {States} {Patent}: 7011791 - {Microfluidic} devices for rotational manipulation of the fluidic interface between multiple flow streams}, number = {7011791}, year = {2006}, month = {mar}, abstract = {Microfluidic devices and methods are provided for enhancing detection of a diffusion pattern formed by particles diffusing between at least two fluid streams in parallel laminar flow such that an interface is formed between them by increasing the dimension of the streams in the diffusion direction. This may be accomplished by flowing the streams through a transforming turn, or by flowing the streams through a channel having diverging walls. Devices and methods are also provided for enhancing diffusion between two streams comprising changing the interface between said streams from a narrow interface to a broad interface.}, url = {http://patft.uspto.gov/netacgi/nph-Parser?Sect1=PTO2\&Sect2=HITOFF\&p=1\&u=\%2Fnetahtml\%2FPTO\%2Fsearch-bool.html\&r=17\&f=G\&l=50\&co1=AND\&d=PTXT\&s1=\%22Weigl\%3B+Bernhard\%22.INNM.\&OS=IN/\%22Weigl;+Bernhard\%22\&RS=IN/\%22Weigl;+Bernhard\%22}, author = {Weigl, Bernhard H. and Bardell, Ronald L. and Kamholz, Andrew and Munson, Matthew and Schilling, Eric and Hawkins, Kenneth} } @article {15, title = {Combination radiofrequency ablation with intratumoral liposomal doxorubicin: effect on drug accumulation and coagulation in multiple tissues and tumor types in animals.}, journal = {Radiology}, volume = {235}, year = {2005}, month = {2005 May}, pages = {469-77}, abstract = {

PURPOSE: To determine whether use of radiofrequency (RF) ablation combined with intravenously (IV) administered liposomal doxorubicin, as compared with use of RF ablation or doxorubicin alone, facilitates increased tissue coagulation and interstitial drug accumulation in animal models.

MATERIALS AND METHODS: The institutional animal care and use committee approved this study. In experiment 1, multiple canine sarcomas were implanted in seven mildly immunosuppressed dogs and grown to a mean diameter of 4.8 cm. Tumors were assigned to three treatment groups: internally cooled RF ablation (12 minutes, 2000-mA pulsed technique) followed by IV liposomal doxorubicin (10 mg per animal) (n = 6), RF ablation alone (n = 6), and liposomal doxorubicin alone (n = 4). In experiment 2, the livers and kidneys of 10 rabbits and the thigh muscles of 10 rats were randomly assigned to one of two treatment groups: conventional RF ablation (90 degrees C +/- 2, 5 minutes) followed by IV liposomal doxorubicin (5 mg per rabbit, 1 mg per rat) or RF ablation alone (n = 5, each). Coagulation diameter and interstitial doxorubicin concentration (tissues were homogenized in acid alcohol, with doxorubicin extracted for 24 hours at 5 degrees C and quantified with fluorimetry) were measured 48 hours after treatment and compared. Multivariate analysis of variance and subsequent pairwise t tests (alpha = .05, two-tailed test) were performed.

RESULTS: Data are means +/- standard errors of the mean. A larger diameter of tumor destruction was observed in canine sarcomas treated with RF ablation-liposomal doxorubicin (3.7 cm +/- 0.6) compared with that in tumors treated with RF ablation (2.3 cm +/- 0.1) or liposomal doxorubicin (0.0 cm +/- 0.0) alone (P < .01). A new finding was a completely necrotic red zone (1.6 cm +/- 0.7) surrounding the central RF ablation-induced white coagulation zone. Greater but nonuniform drug uptake was observed particularly in this red zone (77.0 ng/g +/- 18.2) compared with uptake in the central zone (15.1 ng/g +/- 3.2), peripheral area of untreated tumor (38.9 ng/g +/- 8.0), and tumors treated with liposomal doxorubicin alone (43.9 ng/g +/- 6.7 for all regions) (P < .01 for all individual comparisons). In experiment 2, use of combined therapy led to increased coagulation in all tissues (liver: 17.6 mm +/- 3.1, P = .03; kidney: 11.0 mm +/- 3.1, P = .03; muscle: 13.1 mm +/- 1.3, P < .01) compared with use of RF ablation alone (liver, 13.4 mm +/- 1.5; kidney, 7.9 mm +/- 0.7; muscle, 8.6 mm +/- 0.5). Combined therapy, as compared with liposomal doxorubicin therapy alone, was also associated with increased doxorubicin accumulation in liver, kidney, and muscle (1.56 microg/g +/- 0.34, 4.36 microg/g +/- 1.78, and 3.63 microg/g +/- 1.43, respectively, vs 1.00 microg/g +/- 0.18, 1.23 microg/g +/- 0.32, and 0.87 microg/g +/- 0.53, respectively) (P < or = .01 for all individual comparisons).

CONCLUSION: Use of RF ablation combined with liposomal doxorubicin facilitates increased tissue coagulation and interstitial doxorubicin accumulation in multiple tissues and tumor types and may be useful for treatment of large tumors and achieving an ablative margin within the untreated tissue surrounding RF ablation-treated tumors.

}, keywords = {Animals, Catheter Ablation, Chemotherapy, Adjuvant, Combined Modality Therapy, Doxorubicin, Drug Synergism, Extracellular Fluid, Injections, Intralesional, Kidney, Liver, Muscle, Skeletal, Necrosis, Neoplasm Transplantation, Neoplasms, Multiple Primary, Rabbits, Rats, Rats, Inbred F344, Sarcoma, Experimental, Soft Tissue Neoplasms, Tissue Distribution}, issn = {0033-8419}, doi = {10.1148/radiol.2352031856}, author = {Ahmed, Muneeb and Liu, Zhengjun and Lukyanov, Anatoly N and Signoretti, Sabina and Horkan, Clare and Monsky, Wayne L and Torchilin, Vladimir P and Goldberg, S Nahum} } @article {14, title = {Combined radiofrequency ablation and adjuvant liposomal chemotherapy: effect of chemotherapeutic agent, nanoparticle size, and circulation time.}, journal = {J Vasc Interv Radiol}, volume = {16}, year = {2005}, month = {2005 Oct}, pages = {1365-71}, abstract = {

PURPOSE: To evaluate the effects of liposomal chemotherapeutic agent, nanoparticle size, and liposome circulation time on tissue coagulation and intratumoral drug uptake when radiofrequency (RF) ablation is combined with adjuvant intravenous liposomal chemotherapy in an animal breast tumor model.

MATERIALS AND METHODS: Ninety-one R3230 mammary adenocarcinoma nodules were implanted in 48 Fischer rats. First, standardized RF ablation was combined with intravenous liposomal doxorubicin, cisplatin, or 5-fluorouracil (35 tumors each). Second, three different-sized doxorubicin-containing nanoparticle preparations were combined with standardized RF ablation. Last, two doxorubicin-containing liposome preparations with different blood elimination half-lives were combined with RF ablation. Coagulation diameter and interstitial doxorubicin concentration were measured 48 hours after treatment and compared with use of statistical analysis.

RESULTS: All combinations of RF with liposomal chemotherapy caused significantly greater tumor necrosis than RF alone (P<.05). Significantly increased necrosis was observed with intravenous liposomal RF/doxorubicin and RF/cisplatin compared with intravenous liposomal RF/5-fluorouracil (P<.01). Greater coagulation was observed with RF combined with 100-nm nanoparticles compared with 20-nm or 250-nm nanoparticles (P=.01 and P=.04, respectively). Additionally, greater intratumoral doxorubicin uptake was observed in the group treated with 20-nm nanoparticles compared with those treated with other sizes of nanoparticles (P<.05). RF plus liposomal doxorubicin produced greater coagulation and intratumoral doxorubicin uptake than RF plus 1,2-dipalmitoyl-sn-glycero-3-phosphatidic acid (P<.05).

CONCLUSION: When combined with RF ablation, modification of adjuvant intravenous liposomal chemotherapy, including nanoparticle size, circulation time, and chemotherapeutic agent, can influence intratumoral drug accumulation and tissue coagulation.

}, keywords = {Adenocarcinoma, Animals, Antibiotics, Antineoplastic, Antimetabolites, Antineoplastic, Antineoplastic Agents, Catheter Ablation, Chemotherapy, Adjuvant, Cisplatin, Combined Modality Therapy, Doxorubicin, Fluorouracil, Mammary Neoplasms, Experimental, Nanostructures, Necrosis, Rats, Rats, Inbred F344, Time Factors, Treatment Outcome}, issn = {1051-0443}, doi = {10.1097/01.RVI.0000175324.63304.25}, author = {Ahmed, Muneeb and Lukyanov, Anatoly N and Torchilin, Vladimir and Tournier, Herve and Schneider, Anatoly N and Goldberg, S Nahum} } @article {20, title = {Improving microcirculation is more effective than substitution of red blood cells to correct metabolic disorder in experimental hemorrhagic shock.}, journal = {Shock}, volume = {21}, year = {2004}, month = {2004 Mar}, pages = {235-40}, abstract = {

Microcirculatory perfusion deficits and impaired tissue oxygenation in nonvital organs frequently occur after hemorrhage and they contribute to potentially lethal complications. The aim of this study was to test the influence of colloid osmotic pressure, viscosity, and red blood cell (RBC) content of the resuscitative fluid on metabolic disorder, perfusion, and oxygenation in peripheral tissues. Awake hamsters were subjected to hemorrhage of 50\% and were resuscitated with 25\% of blood volume with solutions containing 6\% pegylated bovine albumin only (PEG-BSA 0) and 6\% PEG-BSA mixed with autologous RBCs to reach 4 g/dL (PEG-BSA 4) and 8 g/dL (PEG-BSA 8) of hemoglobin. PEG-BSA had a viscosity of 4.2 cP and a COP of 116 mmHg. Microhemodynamics and tissue pO2 were assessed in the hamster chamber window preparation with intravital microscopy. Arterial base excess tended to be lower than baseline for PEG-BSA 0 and PEG-BSA 4 (ns), whereas base deficit remained significantly decreased for PEG-BSA 8 (P<0.05 vs. baseline). Oxygen extraction was 91\% +/- 2\% of the oxygen delivery for PEG-BSA 0 compared with 85\% +/- 2\% for PEG-BSA 8 (P<0.05). Functional capillary density was 61\%, 47\%, and 45\% for PEG-BSA 0 (P<0.05 vs. other groups), PEG-BSA 4 and PEG-BSA 8, respectively. We conclude that arterial base excess and oxygen extraction ratio in the tissue was better restored if a higher fraction of PEG-BSA and less RBCs were infused. This was attributed to a more homogeneous distribution of oxygen, as reflected by functional capillary density. Our results suggest that the transfusion trigger in hemorrhagic shock may be shifted toward lower hemoglobin concentrations if highly viscous and oncotic solutions are used.

}, keywords = {Animals, Arteries, Capillaries, Carotid Arteries, Colloids, Cricetinae, Erythrocytes, Hemoglobins, Hydrogen-Ion Concentration, Microcirculation, Osmosis, Osmotic Pressure, Oxygen, Oxygen Consumption, Partial Pressure, Perfusion, Polyethylene Glycols, Pressure, Serum Albumin, Bovine, Shock, Hemorrhagic, Time Factors}, issn = {1073-2322}, doi = {10.1097/01.shk.0000114301.36496.ea}, author = {Wettstein, Reto and Tsai, Amy G and Erni, Dominique and Lukyanov, Anatoly N and Torchilin, Vladimir P and Intaglietta, Marcos} } @article {21, title = {Increased accumulation of PEG-PE micelles in the area of experimental myocardial infarction in rabbits.}, journal = {J Control Release}, volume = {94}, year = {2004}, month = {2004 Jan 8}, pages = {187-93}, abstract = {

Micelles prepared from polyethyleneglycol/phosphatidyl-ethanolamine conjugates (PEG-PE) with a size of 7-20 nm and zeta-potential of approximately -18 mV were administered i.v. to rabbits with experimental myocardial infarctions. Micelles demonstrated a prolonged circulation in the blood (half-life of 2 h) and accumulated in the infarction zone with efficiency more than 8-fold higher as compared to a non-damaged part of the heart muscle. Obtained results suggest that the enhanced permeability and retention (EPR) effect is the primary mechanism of accumulation of microparticles in the infarct areas, and that drug carriers such as PEG-PE micelles can be used for the delivery of therapeutic or diagnostic agents to an area of myocardial infarction.

}, keywords = {Animals, Arterial Occlusive Diseases, Disease Models, Animal, Electrocardiography, Male, Micelles, Myocardial Infarction, Phosphatidylethanolamines, Polyethylene Glycols, Rabbits}, issn = {0168-3659}, author = {Lukyanov, Anatoly N and Hartner, William C and Torchilin, Vladimir P} } @article {18, title = {Micelles from lipid derivatives of water-soluble polymers as delivery systems for poorly soluble drugs.}, journal = {Adv Drug Deliv Rev}, volume = {56}, year = {2004}, month = {2004 May 7}, pages = {1273-89}, abstract = {

Polymeric micelles have a whole set of unique characteristics, which make them very promising drug carriers, in particular, for poorly soluble drugs. Our review article focuses on micelles prepared from conjugates of water-soluble polymers, such as polyethylene glycol (PEG) or polyvinyl pyrrolidone (PVP), with phospholipids or long-chain fatty acids. The preparation of micelles from certain polymer-lipid conjugates and the loading of these micelles with various poorly soluble anticancer agents are discussed. The data on the characterization of micellar preparations in terms of their morphology, stability, longevity in circulation, and ability to spontaneously accumulate in experimental tumors via the enhanced permeability and retention (EPR) effect are presented. The review also considers the preparation of targeted immunomicelles with specific antibodies attached to their surface. Available in vivo results on the efficiency of anticancer drugs incorporated into plain micelles and immunomicelles in animal models are also discussed.

}, keywords = {Animals, Antibodies, Antineoplastic Agents, Chemistry, Pharmaceutical, Drug Carriers, Drug Stability, Lipids, Micelles, Neoplasms, Phosphatidylethanolamines, Polyethylene Glycols, Polymers, Povidone, Solubility, Water}, issn = {0169-409X}, doi = {10.1016/j.addr.2003.12.004}, author = {Lukyanov, Anatoly N and Torchilin, Vladimir P} } @article {17, title = {PEGylated dextran as long-circulating pharmaceutical carrier.}, journal = {J Biomater Sci Polym Ed}, volume = {15}, year = {2004}, month = {2004}, pages = {621-30}, abstract = {

Dextran-polyethylene glycol (PEG) conjugates were synthesized by activating dextran hydroxy groups with carbonyldiimidazole, introducing amino groups by attaching ethylenediamine, and reacting amino groups with a succinimidyl-activated derivative of PEG. Conjugates with an average of 12 and 21 PEG (5 kDa) residues per single dextran (73 kDa) molecule were prepared. These conjugates have circulation half-lives of 5.3 h and 7.0 h, respectively, compared to 4.0 h for non-PEGylated dextran. The modification of dextran with PEG inhibits the uptake of polymer by the major organ of the reticuloendothelial system, the liver. Dextran-PEG conjugates may represent a convenient platform for long-circulating pharmaceutical preparations.

}, keywords = {Animals, Dextrans, Drug Carriers, Female, Half-Life, Mice, Mice, Inbred C57BL, Polyethylene Glycols, Polymers, Tissue Distribution}, issn = {0920-5063}, author = {Lukyanov, Anatoly N and Sawant, Rishikesh M and Hartner, William C and Torchilin, Vladimir P} } @article {19, title = {Preparation and in vitro synergistic anticancer effect of vitamin K3 and 1,8-diazabicyclo[5,4,0]undec-7-ene in poly(ethylene glycol)-diacyllipid micelles.}, journal = {Int J Pharm}, volume = {272}, year = {2004}, month = {2004 Mar 19}, pages = {129-35}, abstract = {

Polymeric micelles consisting of poly(ethylene glycol)-distearoyl phosphoethanolamine conjugates (PEG-DSPE) loaded with Vitamin K3 (VK3) to 0.2 mg of drug/mg of carrier and with 1,8-diazabicyclo[5,4,0]undec-7-ene (DBU) to 0.06 mg of drug/mg of carrier were prepared. These micelles were stable for as long as 6 months during storage at 4 degrees C and did not change their size or release the incorporated drugs. Co-encapsulation of VK3 and DBU into PEG-DSPE micelles resulted in synergistic anticancer effects against both murine and human cancer cells in vitro. The synergism may be explained by the fact that the presence of DBU promotes the escape of drug-loaded micelles from the endosomes of cancer cells directly into the cytoplasm as demonstrated by fluorescent microscopy.

}, keywords = {Animals, Antineoplastic Agents, Bicyclo Compounds, Heterocyclic, Cell Line, Tumor, Drug Combinations, Drug Stability, Drug Synergism, Female, Humans, Mice, Micelles, Microscopy, Fluorescence, Particle Size, Phosphatidylethanolamines, Polyethylene Glycols, Tumor Cells, Cultured, Vitamin K 3}, issn = {0378-5173}, doi = {10.1016/j.ijpharm.2003.12.011}, author = {Wang, Junping and Mongayt, Dmitriy A and Lukyanov, Anatoly N and Levchenko, Tatiana S and Torchilin, Vladimir P} } @article {16, title = {Tumor-targeted liposomes: doxorubicin-loaded long-circulating liposomes modified with anti-cancer antibody.}, journal = {J Control Release}, volume = {100}, year = {2004}, month = {2004 Nov 5}, pages = {135-44}, abstract = {

Commercially available doxorubicin-loaded long-circulating liposomes (Doxil, Alza Pharmaceuticals) were modified with the monoclonal nucleosome (NS)-specific 2C5 antibody (mAb 2C5) that recognizes a broad variety of tumors via the tumor cell surface-bound NSs. For incorporation into liposomes, mAb 2C5 was modified with poly(ethylene glycol)-phosphatidyl ethanolamine conjugate (PEG-PE) with the free PEG terminus activated with the p-nitrophenylcarbonyl group (pNP-PEG-PE). Derivatives of mAb 2C5 containing a variable number of PEG-PE residues (10-32) per protein molecule were prepared with a reasonably good preservation of the antibody specific activity even at the highest degree of modification. PEG-PE-modified antibody quantitatively incorporated into the liposomal membrane of doxorubicin-loaded liposomes with a loss of not more than 20\% of the encapsulated doxorubicin. 2C5-targeted Doxil liposomes acquired the ability to recognize NSs and specifically bind to various tumor cells. Doxorubicin-loaded long-circulating liposomes modified with the mAb 2C5 kill various tumor cells in vitro with the efficiency higher than non-targeted doxorubicin-loaded liposomes.

}, keywords = {Animals, Antibodies, Monoclonal, Antibodies, Neoplasm, Cell Line, Tumor, Doxorubicin, Humans, Liposomes, Mice, Neoplasms, Nucleosomes}, issn = {0168-3659}, doi = {10.1016/j.jconrel.2004.08.007}, author = {Lukyanov, Anatoly N and Elbayoumi, Tamer A and Chakilam, Ananthsrinivas R and Torchilin, Vladimir P} } @patent {bardell_united_2004, title = {United {States} {Patent}: 6674525 - {Split} focusing cytometer}, number = {6674525}, year = {2004}, abstract = {A microcytometer which combines lysing and cytometry into a unified system that achieves blood lysis and white blood cell count in a single device. The device focuses the white cells into a thin ribbon which is then focused into a single stream for analysis.}, url = {http://patft.uspto.gov/netacgi/nph-Parser?Sect1=PTO2\&Sect2=HITOFF\&p=1\&u=\%2Fnetahtml\%2FPTO\%2Fsearch-bool.html\&r=20\&f=G\&l=50\&co1=AND\&d=PTXT\&s1=\%22Weigl\%3B+Bernhard\%22.INNM.\&OS=IN/\%22Weigl;+Bernhard\%22\&RS=IN/\%22Weigl;+Bernhard\%22}, author = {Bardell, Ronald and Weigl, Bernhard H. and Battrell, C. Frederick} } @patent {schulte_united_2004, title = {United {States} {Patent}: 6742661 - {Well}-plate microfluidics}, number = {6742661}, year = {2004}, month = {jun}, abstract = {Microfluidic devices and methods for performing a microfluidic process are presented. A microfluidic device conforms with a standard well plate format. The device includes a well plate comprising a plate and an array of wells formed on or in the plate, and a microfluidic structure connecting at least two of the wells. The device can rely exclusively on gravitational and capillary forces that exist in channels within the microfluidic structure when receiving fluid streams. Also disclosed is a microfluidic device having an array of microfluidic structures, each connecting at least two wells of a well plate, and connecting three or more wells in alternative embodiments. With the present invention, a large number of microfluidic processes or reactions can be performed simultaneously.}, url = {http://patft.uspto.gov/netacgi/nph-Parser?Sect1=PTO2\&Sect2=HITOFF\&p=1\&u=\%2Fnetahtml\%2FPTO\%2Fsearch-bool.html\&r=19\&f=G\&l=50\&co1=AND\&d=PTXT\&s1=\%22Weigl\%3B+Bernhard\%22.INNM.\&OS=IN/\%22Weigl;+Bernhard\%22\&RS=IN/\%22Weigl;+Bernhard\%22}, author = {Schulte, Thomas and Weigl, Bernhard H. and Morris, Chris and Kesler, Natasa} } @patent {weigl_united_2004, title = {United {States} {Patent}: 6743399 - {Pumpless} microfluidics}, number = {6743399}, year = {2004}, month = {jun}, abstract = {A microfluidic device which operates without the need for an external power source. The device includes a body structure, at least one microscale channel within the structure, a port for introducing fluid into the channel, and a power source internal to the structure for propelling the fluid through the channel. Various structures are described which embody the invention.}, url = {http://patft.uspto.gov/netacgi/nph-Parser?Sect1=PTO2\&Sect2=HITOFF\&p=1\&u=\%2Fnetahtml\%2FPTO\%2Fsearch-bool.html\&r=18\&f=G\&l=50\&co1=AND\&d=PTXT\&s1=\%22Weigl\%3B+Bernhard\%22.INNM.\&OS=IN/\%22Weigl;+Bernhard\%22\&RS=IN/\%22Weigl;+Bernhard\%22}, author = {Weigl, Bernhard H. and Williams, Clinton L. and Hayenga, Jon W. and Bardell, Ronald L. and Schulte, Thomas E.} } @article {24, title = {Immunomicelles: targeted pharmaceutical carriers for poorly soluble drugs.}, journal = {Proc Natl Acad Sci U S A}, volume = {100}, year = {2003}, month = {2003 May 13}, pages = {6039-44}, abstract = {

To prepare immunomicelles, new targeted carriers for poorly soluble pharmaceuticals, a procedure has been developed to chemically attach mAbs to reactive groups incorporated into the corona of polymeric micelles made of polyethylene glycol-phosphatidylethanolamine conjugates. Micelle-attached antibodies retained their ability to specifically interact with their antigens. Immunomicelles with attached antitumor mAb 2C5 effectively recognized and bound various cancer cells in vitro and showed an increased accumulation in experimental tumors in mice when compared with nontargeted micelles. Intravenous administration of tumor-specific 2C5 immunomicelles loaded with a sparingly soluble anticancer agent, taxol, into experimental mice bearing Lewis lung carcinoma resulted in an increased accumulation of taxol in the tumor compared with free taxol or taxol in nontargeted micelles and in enhanced tumor growth inhibition. This family of pharmaceutical carriers can be used for the solubilization and enhanced delivery of poorly soluble drugs to various pathological sites in the body.

}, keywords = {Animals, Antibodies, Biological Transport, Breast Neoplasms, Drug Carriers, Drug Design, Female, Fluoresceins, Freeze Fracturing, Humans, Indium Radioisotopes, Kinetics, Lung Neoplasms, Lymphoma, Metabolic Clearance Rate, Mice, Micelles, Microscopy, Electron, Phosphatidylethanolamines, Polyethylene Glycols, Solubility, Tumor Cells, Cultured}, issn = {0027-8424}, doi = {10.1073/pnas.0931428100}, author = {Torchilin, Vladimir P and Lukyanov, Anatoly N and Gao, Zhonggao and Papahadjopoulos-Sternberg, Brigitte} } @article {223, title = {Lab-on-a-chip for drug development.}, journal = {Adv Drug Deliv Rev}, volume = {55}, year = {2003}, month = {2003 Feb 24}, pages = {349-77}, abstract = {

Significant advances have been made in the development of micro-scale technologies for biomedical and drug discovery applications. The first generation of microfluidics-based analytical devices have been designed and are already functional. Microfluidic devices offer unique advantages in sample handling, reagent mixing, separation, and detection. We introduce and review microfluidic concepts, microconstruction techniques, and methods such as flow-injection analysis, electrokinesis, and cell manipulation. Advances in micro-device technology for proteomics, sample preconditioning, immunoassays, electrospray ionization mass spectrometry, and polymerase chain reaction are also reviewed.

}, keywords = {Animals, Humans, Microchemistry, Technology, Pharmaceutical}, issn = {0169-409X}, author = {Weigl, Bernhard H and Bardell, Ron L and Cabrera, Catherine R} } @article {22, title = {Micelles from polyethylene glycol/phosphatidylethanolamine conjugates for tumor drug delivery.}, journal = {J Control Release}, volume = {91}, year = {2003}, month = {2003 Aug 28}, pages = {97-102}, abstract = {

Micelles prepared from polyethylene glycols of various lengths conjugated with phosphatidylethanolamine (PEG-PE) were loaded with various poorly soluble anticancer agents. PEG-PE micelles selectively accumulated in Lewis lung carcinoma (LLC) tumors implanted in mice. Modification of the micelles with tumor specific antibodies further enhanced the efficiency of tumor accumulation.

}, keywords = {Animals, Antineoplastic Agents, Drug Delivery Systems, Enzyme-Linked Immunosorbent Assay, Excipients, Female, Mice, Mice, Inbred C57BL, Micelles, Neoplasms, Particle Size, Phosphatidylethanolamines, Polyethylene Glycols, Solubility}, issn = {0168-3659}, author = {Lukyanov, Anatoly N and Gao, Zhonggao and Torchilin, Vladimir P} } @article {23, title = {PEG-PE/phosphatidylcholine mixed immunomicelles specifically deliver encapsulated taxol to tumor cells of different origin and promote their efficient killing.}, journal = {J Drug Target}, volume = {11}, year = {2003}, month = {2003 Feb}, pages = {87-92}, abstract = {

Mixed micelles were prepared from poly(ethyleneglycol)-distearyl phosphoethanolamine (PEG2000-PE) and egg phosphatidylcholine. The micelles were covalently modified with the nucleosome-specific monoclonal antibody 2C5 known to recognize and bind a variety of tumor cells via their surface-bound nucleosomes. Covalent attachment of 2C5 antibody was performed via a micelle-incorporated PEG-PE with the distal terminus of the PEG block activated with p-nitrophenylcarbonyl group (pNP-PEG-PE). Micelle surface-attached 2C5 antibody maintained its specific activity. 2C5-targeted immunomicelles were able to carry more than 3 wt\% of taxol. Taxol-loaded immunomicelles specifically recognized tumor cell lines of several types. The cytotoxicity of 2C5-targeted taxol-loaded immunomicelles in a cell culture model was much higher when compared with free taxol or taxol in non-targeted micelles.

}, keywords = {Animals, Antibodies, Monoclonal, Antineoplastic Agents, Cell Survival, Chromatography, High Pressure Liquid, Drug Carriers, Electrophoresis, Polyacrylamide Gel, Mice, Micelles, Nucleosomes, Paclitaxel, Particle Size, Phosphatidylcholines, Phosphatidylethanolamines, Polyethylene Glycols, Tumor Cells, Cultured}, issn = {1061-186X}, doi = {10.1080/1061186031000138623}, author = {Gao, Z and Lukyanov, A N and Chakilam, A R and Torchilin, V P} } @article {25, title = {Peptide and protein drug delivery to and into tumors: challenges and solutions.}, journal = {Drug Discov Today}, volume = {8}, year = {2003}, month = {2003 Mar 15}, pages = {259-66}, abstract = {

The potential of peptide and protein anticancer agents has yet to be realized owing to the many unresolved problems concerning their delivery to the site of a tumor and into tumor cells. However, our understanding of the mechanisms underlying the biological fate and biodistribution of protein and peptide drugs has advanced to the stage where methods that use or influence these mechanisms are now available. There are different approaches that can improve the stability, longevity and targeting of peptides and proteins in the body, such as their modification with various soluble polymers, incorporation into microparticular drug carriers, enhanced permeability and retention effect-based tumor targeting and the use of targeting moieties. Furthermore, new approaches to intracellular drug delivery, including the use of transduction proteins and peptides, are being developed. These advances promise the delivery of a new generation of anticancer drugs.

}, keywords = {Animals, Antineoplastic Agents, Biological Transport, Cell Membrane Permeability, Drug Carriers, Drug Delivery Systems, Humans, Neoplasms, Peptides, Proteins, Tissue Distribution}, issn = {1359-6446}, author = {Torchilin, Vladimir P and Lukyanov, Anatoly N} } @patent {weigl_united_2003-2, title = {United {States} {Patent}: 6541213 - {Microscale} diffusion immunoassay}, number = {6541213}, year = {2003}, month = {apr}, abstract = {Methods and apparatuses are provided for determining presence and concentration of analytes by exploiting molecular binding reactions and differential diffusion rates. Analyte particles and binding particles are allowed to diffuse toward each other, and slowing of the diffusion front is detected when they meet. From the position of the diffusion front, presence and concentration of analyte particles can be determined. One embodiment provides a competitive immunoassay in a microfluidic format. This diffusion immunoassay (DIA) relies on measuring the concentration of labeled antigen along one dimension of a microchannel after allowing it to diffuse for a short time into a region containing specific antibodies. A simple microfluidic device, the T-Sensor, was used to implement a DIA to measure the concentration of phenytoin, a small drug molecule. Concentrations of analyte over the range of 50 to 1600 nM can be measured in less than a minute. The assay is homogeneous, rapid, requires only microliter volumes of reagents and sample, and is applicable to a wide range of analytes, including therapeutic drugs, molecular biological markers, and environmental contaminants. Methods for separating particles of similar size in a diffusion separator are also provided.}, url = {http://patft.uspto.gov/netacgi/nph-Parser?Sect1=PTO2\&Sect2=HITOFF\&p=1\&u=\%2Fnetahtml\%2FPTO\%2Fsearch-bool.html\&r=23\&f=G\&l=50\&co1=AND\&d=PTXT\&s1=\%22Weigl\%3B+Bernhard\%22.INNM.\&OS=IN/\%22Weigl;+Bernhard\%22\&RS=IN/\%22Weigl;+Bernhard\%22}, author = {Weigl, Bernhard H. and Yager, Paul and Kamholz, Andrew and Hatch, Anson} } @patent {weigl_united_2003-1, title = {United {States} {Patent}: 6557427 - {Capillaries} for fluid movement within microfluidic channels}, number = {6557427}, year = {2003}, month = {may}, abstract = {A capillary for introduction of whole blood into an analysis device. The capillary has a variable volume along its length, which allows the liquid sample to be drawn into the interior of the cartridge, away from the inlet, reducing the risk of contamination of the sample from the outside.}, url = {http://patft.uspto.gov/netacgi/nph-Parser?Sect1=PTO2\&Sect2=HITOFF\&p=1\&u=\%2Fnetahtml\%2FPTO\%2Fsearch-bool.html\&r=22\&f=G\&l=50\&co1=AND\&d=PTXT\&s1=\%22Weigl\%3B+Bernhard\%22.INNM.\&OS=IN/\%22Weigl;+Bernhard\%22\&RS=IN/\%22Weigl;+Bernhard\%22}, author = {Weigl, Bernhard H. and Klein, Gerald L. and Bardell, Ronald L. and Battrell, C. Frederick} } @patent {weigl_united_2003, title = {United {States} {Patent}: 6582963 - {Simultaneous} analyte determination and reference balancing in reference {T}-sensor devices}, number = {6582963}, year = {2003}, abstract = {A reference T-sensor system is provided for detecting the presence and/or measuring the concentration of analyte particles in a sample stream. The system includes: a) a laminar flow channel; b) three or more inlets in fluid connection with the laminar flow channel for respectively conducting into the laminar flow channel (1) an indicator stream which may include an indicator substance which indicates the presence of analyte particles by a detectable change in property when contacted with the analyte particles, (2) the sample stream, and (3) a reference stream, which can be a control stream and/or an internal standard stream; c) wherein the laminar flow channel has a depth and/or width sufficiently small to allow laminar flow of the streams and a length sufficient to allow particles of the analyte to diffuse into the indicator stream to form a detection area; and (d) an outlet for conducting the streams out of the laminar flow channel preferably to form a single mixed stream.}, url = {http://patft.uspto.gov/netacgi/nph-Parser?Sect1=PTO2\&Sect2=HITOFF\&p=1\&u=\%2Fnetahtml\%2FPTO\%2Fsearch-bool.html\&r=21\&f=G\&l=50\&co1=AND\&d=PTXT\&s1=\%22Weigl\%3B+Bernhard\%22.INNM.\&OS=IN/\%22Weigl;+Bernhard\%22\&RS=IN/\%22Weigl;+Bernhard\%22}, author = {Weigl, Bernhard H. and Holl, Mark R. and Zebert, Diane and Kenny, Margaret and Wu, Caicai} } @article {224, title = {Initial study of using a laminar fluid diffusion interface for sample preparation in high-performance liquid chromatography.}, journal = {J Chromatogr A}, volume = {954}, year = {2002}, month = {2002 Apr 19}, pages = {33-40}, abstract = {

This report describes a new microfluidic device called the H Filter for sample preparation prior to HPLC. The H Filters make possible a diffusional transfer of an analyte from a sample stream into a stream of a "receiver" fluid. Existing mathematical models can be used for optimizing experimental conditions. The authors have selected the extraction of the antibiotic cephradine from blood to demonstrate the utility of the new device. The extracts of blood samples spiked with cephradine levels between 0.2 and 100 microg/ml were analyzed using a C8 reversed-phase column and UV detection at 260 nm. The HPLC results were in good agreement with theory. The recovery of 32.2+/-2.8\% was uniform over the entire range of cephradine concentrations. The new method completely avoids the use of centrifuges, that is otherwise typical for most current methodologies for the preparation of blood samples prior to HPLC analysis.

}, keywords = {Cephradine, Chromatography, High Pressure Liquid, Diffusion, Humans, Reference Standards, Spectrophotometry, Ultraviolet}, issn = {0021-9673}, author = {Jandik, P and Weigl, B H and Kessler, N and Cheng, J and Morris, C J and Schulte, T and Avdalovic, N} } @article {226, title = {Lab-on-a-chip-based separation and detection technology for clinical diagnostics.}, journal = {Am Clin Lab}, volume = {21}, year = {2002}, month = {2002 Mar}, pages = {8-13}, keywords = {Chemistry, Clinical, Cytological Techniques, Humans, Miniaturization}, issn = {1041-3235}, author = {Weigl, Bernhard H and Hedine, Karen} } @article {28, title = {Liposome clearance in mice: the effect of a separate and combined presence of surface charge and polymer coating.}, journal = {Int J Pharm}, volume = {240}, year = {2002}, month = {2002 Jun 20}, pages = {95-102}, abstract = {

The purpose of our work was to compare the biodistribution of liposomes with different surface properties. Phosphatidylcholine (PC)/cholesterol (Chol) liposomes were prepared containing 6\% mol of a charged lipid (stearylamine, SA; phosphatidic acid, PA; or phosphatidyl serine, PS) and/or polyethylene glycol (PEG)-PE of different MW (750 and 5000). zeta-Potentials and liposome clearance in mice were investigated. In vitro, the attachment of PEG in a similar fashion neutralizes the effect of any charged component. In vivo, the chemical nature of a charged lipid becomes important. Both short PEG750 and longer PEG5000 inhibit the clearance of positively charged SA-liposomes, while only longer PEG5000 inhibits the clearance of negatively charged PA-liposomes and none of the PEGs inhibit the clearance of negatively charged PS-liposomes. The opsonins with different molecular size may be involved in the clearance of liposomes containing different charged lipids.

}, keywords = {Animals, Electrochemistry, Liposomes, Liver, Metabolic Clearance Rate, Mice, Particle Size, Polyethylene Glycols, Surface Properties, Tissue Distribution}, issn = {0378-5173}, author = {Levchenko, Tatiana S and Rammohan, Ram and Lukyanov, Anatoly N and Whiteman, Kathleen R and Torchilin, Vladimir P} } @article {225, title = {Microfluidic technologies in clinical diagnostics.}, journal = {Clin Chim Acta}, volume = {321}, year = {2002}, month = {2002 Jul}, pages = {1-10}, abstract = {

BACKGROUND: Laboratory instrumentation and analytical devices are becoming smaller, simpler, and smarter. This trend to miniaturization extends to fluid handling and fluid analysis. However, fluid behavior undergoes significant changes as geometric scale decreases. The laminar flow behavior of fluids in microfluidic devices must be accommodated in the design and development of clinical and bio-clinical miniaturized systems.

CONCLUSION: The scale of chemical and clinical analysis systems will continue to decrease. The capability to manufacture smaller fluidic devices and to quantitatively monitor smaller volumes of liquids bring this process of miniaturization into the domain of laminar flow. New and enabling technologies are being developed using the unique diffusion-based characteristics of the laminar flow domain for sample preparation and analysis. These new analytical systems will have a significant impact on the future of clinical diagnostics.

}, keywords = {Biomechanical Phenomena, Body Fluids, Chemistry, Clinical, Chromatography, High Pressure Liquid, Diffusion, Humans, Microchemistry, Miniaturization}, issn = {0009-8981}, author = {Schulte, Thomas H and Bardell, Ron L and Weigl, Bernhard H} } @article {29, title = {Percutaneous tumor ablation: increased necrosis with combined radio-frequency ablation and intravenous liposomal doxorubicin in a rat breast tumor model.}, journal = {Radiology}, volume = {222}, year = {2002}, month = {2002 Mar}, pages = {797-804}, abstract = {

PURPOSE: To determine whether a combination of intravenous liposomal doxorubicin and radio-frequency (RF) ablation increases tumor destruction compared with RF alone in an animal tumor model.

MATERIALS AND METHODS: R3230 mammary adenocarcinoma 1.4-1.8-cm- diameter nodules were implanted subcutaneously in 132 female Fischer rats. Initially, tumors were treated with (a) conventional, monopolar RF (mean, 250 mA +/- 25 [SD] at 70 degrees C +/- 1 for 5 minutes) ablation alone, (b) RF ablation followed by intravenous administration of 1 mg of liposomal doxorubicin, (c) RF ablation followed by intravenous administration of 1 mg of empty liposomes, (d) RF ablation and direct intratumoral administration of liposomal doxorubicin, or (e) no treatment. Subsequently, the dose (0.06-2.00 mg) of liposomal doxorubicin, the timing of administration (3 days before to 3 days after RF ablation), and the time of pathologic examination (0-72 hours after treatment) were varied.

RESULTS: Mean coagulation diameter for treated tumors follows: 6.7 mm +/- 0.6, RF ablation alone; 11.1 mm +/- 1.5, RF ablation and intravenous administration of empty liposomes (P <.05, compared with RF ablation alone); and 8.4 mm +/- 1.1, RF ablation with intratumoral administration of liposomal doxorubicin (P <.05, compared with RF ablation alone). Maximal increased mean coagulation diameter (13.1 mm +/- 1.5) was observed with a combination of liposomal doxorubicin and RF ablation (P <.001, for all comparisons). The increased coagulation for combination therapy developed over 48 hours after therapy. Coagulation diameter did not vary with the doxorubicin concentration range and was not dependent on the timing of administration of liposomal doxorubicin from 3 days before to 24 hours after RF ablation.

CONCLUSION: Intravenous administration of liposomal doxorubicin can improve RF ablation, since it increases coagulation diameter in solid tumors compared with RF ablation alone or a combination of RF ablation with administration of empty liposomes.

}, keywords = {Animals, Antineoplastic Agents, Catheter Ablation, Combined Modality Therapy, Doxorubicin, Female, Infusions, Intravenous, Liposomes, Mammary Neoplasms, Experimental, Necrosis, Neoplasm Transplantation, Polyethylene Glycols, Rats, Rats, Inbred F344, Surface-Active Agents, Tumor Cells, Cultured}, issn = {0033-8419}, doi = {10.1148/radiol.2223010861}, author = {Goldberg, S Nahum and Girnan, Geoffrey D and Lukyanov, Anatoly N and Ahmed, Muneeb and Monsky, Wayne L and Gazelle, G Scott and Huertas, Juan Carlos and Stuart, Keith E and Jacobs, Timothy and Torchillin, Vladimir P and Halpern, Elkan F and Kruskal, Jonathan B} } @article {26, title = {Polyethylene glycol-diacyllipid micelles demonstrate increased acculumation in subcutaneous tumors in mice.}, journal = {Pharm Res}, volume = {19}, year = {2002}, month = {2002 Oct}, pages = {1424-9}, abstract = {

PURPOSE: The purpose of this work is to study the potential of micelles prepared from amphiphilic polyethelene glycol/phosphatidylethanolamine (PEG-PE) conjugates as a particulate drug delivery system capable of accumulation in tumors via the enhanced permeability and retention (EPR) effect.

METHODS: Micelles were prepared from PEGs of different molecular lengths conjugated with PE. The micelles were characterized by fluorescence-based critical micellization concentration (CMC) measure ments, dynamic light scattering, and HPLC. Blood clearance an tumor accumulation of 111In-labeled micelles were studied in mic with subcutaneously established Lewis lung carcinoma (LLC) and EL4 T lymphoma (EL4) tumors.

RESULTS: Various versions of PEG-PE conjugates with PEG blocks ranging from 750 to 5000 Da formed very stable low CMC micelles at all concentrations down to 10(-5) M. The size of the micelles varie between 7 and 35 nm depending on the length of the PEG block. Micelles remained intact after prolonged incubation with the blood serum. Upon intravenous administration into mice, the micelles demonstrated circulation longevity, and they efficiently and selectively accumulated in both subcutaneous Lewis lung carcinoma and EL4 T lymphoma tumors.

CONCLUSIONS: PEG-PE conjugates form very stable, long-circulating micelles. These micelles efficiently accumulate in tumors in vivo an may potentially be used as a tumor-specific delivery system for poorly soluble anticancer drugs.

}, keywords = {Animals, Carcinoma, Lewis Lung, Female, Injections, Subcutaneous, Mice, Mice, Inbred C57BL, Micelles, Phosphatidylethanolamines, Polyethylene Glycols, Tumor Cells, Cultured, Xenograft Model Antitumor Assays}, issn = {0724-8741}, author = {Lukyanov, Anatoly N and Gao, Zhonggao and Mazzola, Laureen and Torchilin, Vladimir P} } @article {27, title = {Radio-frequency ablation increases intratumoral liposomal doxorubicin accumulation in a rat breast tumor model.}, journal = {Radiology}, volume = {224}, year = {2002}, month = {2002 Sep}, pages = {823-9}, abstract = {

PURPOSE: To determine whether intratumoral accumulation of liposomal doxorubicin or free unencapsulated doxorubicin is increased when combined with radio-frequency (RF) ablation.

MATERIALS AND METHODS: Two 1.2-1.5-cm R3230 mammary adenocarcinomas were grown within the mammary fat pads of 19 female Fischer rats. One tumor of each pair was treated with RF ablation (tip temperature, 70 degrees C +/- 2 [SD]; 120 mA +/- 75) for 5 minutes, whereas the other tumor was a control. Intravenous liposomal doxorubicin (1 mg in 500 micro L, n = 6) or intravenous free unencapsulated doxorubicin (n = 7) was administered immediately following RF ablation. Doxorubicin was extracted in acid alcohol from tumors 24 hours following RF ablation, and fluorescent spectrophotometry was used to quantify extracted doxorubicin. Comparisons of intratumoral doxorubicin accumulation in tumors treated with RF ablation and in untreated tumors were analyzed with parametric (paired Student t test) and nonparametric (Wilcoxon rank sum test) statistics. Findings at autoradiography with densitometry (six additional tumors) demonstrated the spatial distribution of the intratumoral accumulation of liposomal doxorubicin.

RESULTS: When RF ablation preceded administration of liposomal doxorubicin, mean intratumoral doxorubicin concentration was 5.6 micro g/g +/- 2.1 (range, 1.9-7.7 micro g/g), whereas 1.0 micro g/g +/- 0.4 (range, 0.5-1.5 micro g/g) was present in control tumors not treated with RF ablation (P <.05). Thus, there was a mean 7.1-fold +/- 4.9 increase in intratumoral doxorubicin accumulation following RF ablation (range, 2.1-14.5-fold) compared with the amount without RF pretreatment (P <.05). Increased intratumoral accumulation was not seen in animals receiving free doxorubicin with (mean, 0.4 micro g/g +/- 0.1) or without (mean, 0.8 micro g/g +/- 0.4) RF pretreatment (P =.07). Autoradiographic findings demonstrated accumulation of liposomal doxorubicin in a peripheral rim of tumor adjacent to the zone of coagulation.

CONCLUSION: RF ablation augments the delivery of systemic antineoplastic agents such as liposomal doxorubicin.

}, keywords = {Adenocarcinoma, Animals, Antineoplastic Agents, Autoradiography, Catheter Ablation, Doxorubicin, Female, Injections, Intravenous, Liposomes, Mammary Neoplasms, Experimental, Rats, Rats, Inbred F344}, issn = {0033-8419}, doi = {10.1148/radiol.2243011421}, author = {Monsky, Wayne L and Kruskal, Jonathan B and Lukyanov, Anatoly N and Girnun, Geoffrey D and Ahmed, Muneeb and Gazelle, G Scott and Huertas, Juan Carlos and Stuart, Keith E and Torchilin, Vladimir P and Goldberg, S Nahum} } @patent {weigl_united_2002, title = {United {States} {Patent}: 6409832 - {Protein} crystallization in microfluidic structures}, number = {6409832}, year = {2002}, month = {jun}, abstract = {A device for promoting protein crystal growth (PCG) using microfluidic channels. A protein sample and a solvent solution are combined within a microfluidic channel having laminar flow characteristics which forms diffusion zones, providing for a well defined crystallization. Protein crystals can then be harvested from the device. The device is particularly suited for microgravity conditions.}, url = {http://patft.uspto.gov/netacgi/nph-Parser?Sect1=PTO2\&Sect2=HITOFF\&p=1\&u=\%2Fnetahtml\%2FPTO\%2Fsearch-bool.html\&r=26\&f=G\&l=50\&co1=AND\&d=PTXT\&s1=\%22Weigl\%3B+Bernhard\%22.INNM.\&OS=IN/\%22Weigl;+Bernhard\%22\&RS=IN/\%22Weigl;+Bernhard\%22}, author = {Weigl, Bernhard H. and Sygusch, Jurgen and CA} } @patent {weigl_united_2002-2, title = {United {States} {Patent}: 6454945 - {Microfabricated} devices and methods}, number = {6454945}, year = {2002}, month = {sep}, abstract = {This invention provides microfabricated systems for extraction of desired particles from a sample stream containing desired and undesired particles. The sample stream is placed in laminar flow contact with an extraction stream under conditions in which inertial effects are negligible. The contact between the two streams is maintained for a sufficient period of time to allow differential transport of the desired particles from the sample stream into the extraction stream. In a preferred embodiment the differential transport mechanism is diffusion. The extraction system of this invention coupled to a microfabricated diffusion-based mixing device and/or sensing means allows picoliter quantities of fluid to be processed or analyzed on devices no larger than silicon wafers. Such diffusion-based mixing or sensing devices are preferably channel cell systems for detecting the presence and/or measuring the quantity of analyte particles in a sample stream.}, url = {http://patft.uspto.gov/netacgi/nph-Parser?Sect1=PTO2\&Sect2=HITOFF\&p=1\&u=\%2Fnetahtml\%2FPTO\%2Fsearch-bool.html\&r=25\&f=G\&l=50\&co1=AND\&d=PTXT\&s1=\%22Weigl\%3B+Bernhard\%22.INNM.\&OS=IN/\%22Weigl;+Bernhard\%22\&RS=IN/\%22Weigl;+Bernhard\%22}, author = {Weigl, Bernhard H. and Yager, Paul and Brody, James P. and Holl, Mark R. and Forster, Fred K. and Altendorf, Eric and Galambos, Paul C. and Kenny, Margaret and Schutte, David and Hixson, Gregory and Zebert, Diane and Kamholz, Andrew and Wu, Caicai} } @patent {weigl_united_2002-1, title = {United {States} {Patent}: 6488896 - {Microfluidic} analysis cartridge}, number = {6488896}, year = {2002}, abstract = {A device for analyzing sample solutions such as whole blood based on coagulation and agglutination which requires no external power source or moving parts to perform the analysis. Single disposable cartridges for performing blood typing assays can be constructed using this technology.}, url = {http://patft.uspto.gov/netacgi/nph-Parser?Sect1=PTO2\&Sect2=HITOFF\&p=1\&u=\%2Fnetahtml\%2FPTO\%2Fsearch-bool.html\&r=24\&f=G\&l=50\&co1=AND\&d=PTXT\&s1=\%22Weigl\%3B+Bernhard\%22.INNM.\&OS=IN/\%22Weigl;+Bernhard\%22\&RS=IN/\%22Weigl;+Bernhard\%22}, author = {Weigl, Bernhard H. and Klein, Gerald L. and Bardell, Ronald L. and Williams, Clinton L. and Schulte, Thomas H.} } @article {227, title = {Lab-on-a-chip sample preparation using laminar fluid diffusion interfaces--computational fluid dynamics model results and fluidic verification experiments.}, journal = {Fresenius J Anal Chem}, volume = {371}, year = {2001}, month = {2001 Sep}, pages = {97-105}, abstract = {

Microfluidic structures for the generation of laminar fluid diffusion interfaces (LFDIs) for sample preparation and analysis are discussed. Experimental data and the results of fluid modeling are shown. LFDIs are generated when two or more streams flow in parallel in a single microfluidic structure without any mixing of the fluids other than by diffusion of particles across the diffusion interface. It has been shown that such structures can be used for diffusion-based separation and detection applications. The method has been applied to DNA desalting, the extraction of small proteins from whole blood samples, and the detection of various constituents in whole blood, among other examples. In this paper the design and manufacture of self-contained microfluidic cartridges for the extraction of small molecules from a mixture of small and large molecules by diffusion is demonstrated. The cards are operated without any external instrumentation, and use hydrostatic pressure as the driving force. The performance of the cartridges is illustrated by separating fluorescein from a mixture of fluorescein and dextran of molecular weight 2 x 10(6). In a single pass, 98.6\% of dextran was retained in the product whereas 43.1\% of fluorescein was removed. The method is adjustable for different separation requirements, and computational fluid dynamics (CFD) models are shown that demonstrate the tuning of various microfluidic parameters to optimize separation performance. Other applications of LFDIs for establishment of stable concentration gradients, and the exposure of chemical constituents or biological particles to these concentration gradients are shown qualitatively. Microfluidic chips have been designed for high-throughput screening applications that enable the uniform and controlled exposure of cells to lysing agents, thus enabling the differentiation of cells by their sensitivity to specific agents in an on-chip cytometer coupled directly to the lysing structure.

}, keywords = {Chemistry Techniques, Analytical, Dextrans, Diffusion, Equipment Design, Fluorescein, Microchemistry, Models, Chemical, Molecular Weight, Rheology, Viscosity}, issn = {0937-0633}, author = {Weigl, B H and Bardell, R L and Kesler, N and Morris, C J} } @article {30, title = {p-Nitrophenylcarbonyl-PEG-PE-liposomes: fast and simple attachment of specific ligands, including monoclonal antibodies, to distal ends of PEG chains via p-nitrophenylcarbonyl groups.}, journal = {Biochim Biophys Acta}, volume = {1511}, year = {2001}, month = {2001 Apr 2}, pages = {397-411}, abstract = {

We have attempted to simplify the procedure for coupling various ligands to distal ends of liposome-grafted polyethylene glycol (PEG) chains and to make it applicable for single-step binding of a large variety of a primary amino group-containing substances, including proteins and small molecules. With this in mind, we have introduced a new amphiphilic PEG derivative, p-nitrophenylcarbonyl-PEG-1,2-dioleoyl-sn-glycero-3-phosphoethanolamine (pNP-PEG-DOPE), synthesized by reaction of DOPE with excess of bis(p-nitrophenylcarbonyl)-PEG in a chloroform/triethylamine mixture. pNP-PEG-DOPE readily incorporates into liposomes via its PE residue, and easily binds primary amino group-containing ligands via its water-exposed pNP groups, forming stable and non-toxic urethane (carbamate) bonds. The reaction between the pNP group and the ligand amino group proceeds easily and quantitatively at pH around 8.0, and remaining free pNP groups are promptly eliminated by spontaneous hydrolysis. Therefore, pNP-PEG-DOPE could serve as a very convenient tool for protein attachment to the distal ends of liposome-grafted PEG chains. To investigate the applicability of the suggested protocol for the preparation of long-circulating targeted liposomes, we have coupled several proteins, such as concanavalin A (ConA), wheat germ agglutinin (WGA), avidin, monoclonal antimyosin antibody 2G4 (mon2G4), and monoclonal antinucleosome antibody 2C5 (mon2C5) to PEG-liposomes via terminal pNP groups and studied whether the specific activity of these immobilized proteins is preserved. The method permits the binding of several dozens protein molecules per single 200 nm liposome. All bound proteins completely preserve their specific activity. Lectin-liposomes are agglutinated by the appropriate polyvalent substrates (mannan for ConA-liposomes and glycophorin for WGA-liposomes); avidin-liposomes specifically bind with biotin-agarose; antibody-liposomes demonstrate high specific binding to the substrate monolayer both in the direct binding assay and in ELISA. A comparison of the suggested method with the method of direct membrane incorporation was made. The effect of the concentration of liposome-grafted PEG on the preservation of specific protein activity in different coupling protocols was also investigated. It was also shown that pNP-PEG-DOPE-liposomes with and without attached ligands demonstrate increased stability in mouse serum.

}, keywords = {Animals, Antibodies, Monoclonal, Avidin, Drug Stability, Hydrogen-Ion Concentration, Lectins, Ligands, Liposomes, Mice, Models, Chemical, Nitro Compounds, Phosphatidylethanolamines, Polyethylene Glycols, Protein Binding, Proteins, Surface-Active Agents}, issn = {0006-3002}, author = {Torchilin, V P and Levchenko, T S and Lukyanov, A N and Khaw, B A and Klibanov, A L and Rammohan, R and Samokhin, G P and Whiteman, K R} } @article {228, title = {A rapid diffusion immunoassay in a T-sensor.}, journal = {Nat Biotechnol}, volume = {19}, year = {2001}, month = {2001 May}, pages = {461-5}, abstract = {

We have developed a rapid diffusion immunoassay that allows measurement of small molecules down to subnanomolar concentrations in <1 min. This competitive assay is based on measuring the distribution of a labeled probe molecule after it diffuses for a short time from one region into another region containing antigen-specific antibodies. The assay was demonstrated in the T-sensor, a simple microfluidic device that places two fluid streams in contact and allows interdiffusion of their components. The model analyte was phenytoin, a typical small drug molecule. Clinically relevant levels were measured in blood diluted from 10- to 400-fold in buffer containing the labeled antigen. Removal of cells from blood samples was not necessary. This assay compared favorably with fluorescence polarization immunoassay (FPIA) measurements. Numerical simulations agree well with experimental results and provide insight for predicting assay performance and limitations. The assay is homogeneous, requires <1 microl of reagents and sample, and is applicable to a wide range of analytes.

}, keywords = {Antibody Specificity, Antigen-Antibody Complex, Binding, Competitive, Diffusion, Fluorescence Polarization Immunoassay, Immunoassay, Molecular Weight, Phenytoin, Rheology}, issn = {1087-0156}, doi = {10.1038/88135}, author = {Hatch, A and Kamholz, A E and Hawkins, K R and Munson, M S and Schilling, E A and Weigl, B H and Yager, P} } @patent {weigl_united_2001-1, title = {United {States} {Patent}: 6171865 - {Simultaneous} analyte determination and reference balancing in reference {T}-sensor devices}, number = {6171865}, year = {2001}, month = {jan}, abstract = {A reference sensor system is provided for detecting the presence and/or measuring the concentration of analyte particles in a sample stream. The system includes: a) a laminar flow channel; b) three or more inlet means in fluid connection with the laminar flow channel for respectively conducting into the laminar flow channel (1) an indicator stream which may include an indicator substance which indicates the presence of the analyte particles, (2) the sample stream, and (3) a reference stream, which can be a control stream and/or internal standard stream; and, c) wherein the laminar flow channel has a depth and/or width sufficiently small to allow laminar flow of said streams and a length sufficient to allow particles of the analyte to diffuse into the indicator stream to form a detection area. Branching channels may be provided as outlet means for conducting the streams out of the laminar flow channel. Also provided are methods of using the device to improve accuracy and increase convenience of measuring the concentration of analytes in a sample. Monitoring reference stream(s) in laminar flow with sample stream(s) allows for calibration or for monitoring or correcting for the effects of experimental conditions which might otherwise degrade accuracy. A reference stream which serves as both a control stream and an internal standard stream is convenient and economical. The device of this invention also needs less frequent calibration than previously-known fluid analysis devices because the devices and methods of this invention provide for continuous and simultaneous quality control and internal standardization.}, url = {http://patft.uspto.gov/netacgi/nph-Parser?Sect1=PTO2\&Sect2=HITOFF\&p=1\&u=\%2Fnetahtml\%2FPTO\%2Fsearch-bool.html\&r=30\&f=G\&l=50\&co1=AND\&d=PTXT\&s1=\%22Weigl\%3B+Bernhard\%22.INNM.\&OS=IN/\%22Weigl;+Bernhard\%22\&RS=IN/\%22Weigl;+Bernhard\%22}, author = {Weigl, Bernhard H. and Holl, Mark R. and Zebert, Diane and Kenny, Margaret and Wu, Caicai} } @patent {wu_united_2001, title = {United {States} {Patent}: 6221677 - {Simultaneous} particle separation and chemical reaction}, number = {6221677}, year = {2001}, abstract = {This invention provides a method and apparatus for detecting the presence of analyte particles in a sample fluid also comprising larger particles, particularly blood. It exploits diffusion to provide simultaneous filtering of the larger particles and reaction of the analyte particles. A sample stream and a reagent stream join on the upstream end of a laminar flow reaction channel and flow in adjacent laminar streams. The reagents can be in solution or immobilized on a bead. The analyte particles diffuse from the sample stream into the reagent stream, leaving behind the larger particles in the residual sample stream. In the reagent stream the analyte particles react with reagent particles and form product particles, thereby creating a product stream. At the downstream end of the reaction channel, the residual sample stream and the product stream are divided. The product particles are then detected, preferably optically, in the product stream. Prior to detection, the product stream can undergo further filtering or separation, or can join a second reagent stream to form secondary product particles. This apparatus and method can be used to implement competitive immunoassays or sandwich immunoassays using enzymatically or fluorescently labeled immunoreagents. The apparatus and method can also be used to synthesize products, in which case two reagent streams join in the laminar flow reaction channel.}, url = {http://patft.uspto.gov/netacgi/nph-Parser?Sect1=PTO2\&Sect2=HITOFF\&p=1\&u=\%2Fnetahtml\%2FPTO\%2Fsearch-bool.html\&r=29\&f=G\&l=50\&co1=AND\&d=PTXT\&s1=\%22Weigl\%3B+Bernhard\%22.INNM.\&OS=IN/\%22Weigl;+Bernhard\%22\&RS=IN/\%22Weigl;+Bernhard\%22}, author = {Wu, Caicai and Weigl, Bernhard and Kenny, Margaret A. and Yager, Paul} } @patent {forster_united_2001, title = {United {States} {Patent}: 6227809 - {Method} for making micropumps}, number = {6227809}, year = {2001}, month = {may}, abstract = {This invention provides a method by which the performance of reciprocating NMPV (No-Moving-Parts-Valve) micropumps can be optimized for a given choice of valve design, e.g. for diffuser/nozzle valves, rectifier valves etc. The method can more generally be used to design and produce NMPV micropumps with structures optimized for maximal pump performance. The method can further be used to design and construct NMPV pumps significantly smaller in size than those currently available to the art without significant loss in pump performance.}, url = {http://patft.uspto.gov/netacgi/nph-Parser?Sect1=PTO2\&Sect2=HITOFF\&p=1\&u=\%2Fnetahtml\%2FPTO\%2Fsearch-bool.html\&r=16\&f=G\&l=50\&co1=AND\&d=PTXT\&s1=\%22Bardell\%3B+Ron\%22.INNM.\&OS=IN/\%22Bardell;+Ron\%22\&RS=IN/\%22Bardell;+Ron\%22}, author = {Forster, Fred K. and Bardell, Ron L. and Sharma, Nigel R.} } @patent {weigl_united_2001, title = {United {States} {Patent}: 6294296 - {Method} and device for mutually aligning a mask pattern formed in a mask and a substrate}, number = {6294296}, year = {2001}, month = {sep}, abstract = {In a method for mutually aligning a mask pattern formed in a mask 1 and a substrate 2, on which the mask pattern is to be imaged, by using setting marks 12a, 12b and 13a or 13b in the mask 1 and in the substrate 2, the alignment is performed with the aid of an imaging system and a light beam with polarized light 9. A phase shift for the first diffraction orders 20 is undertaken in the beam path 9a, 9b. Higher diffraction orders 21 and unwanted light are filtered out after the phase shift, and after the filtering out the light beams of the first diffraction orders 20 are detected, and the result is evaluated for the purpose of alignment.}, url = {http://patft.uspto.gov/netacgi/nph-Parser?Sect1=PTO2\&Sect2=HITOFF\&p=1\&u=\%2Fnetahtml\%2FPTO\%2Fsearch-bool.html\&r=28\&f=G\&l=50\&co1=AND\&d=PTXT\&s1=\%22Weigl\%3B+Bernhard\%22.INNM.\&OS=IN/\%22Weigl;+Bernhard\%22\&RS=IN/\%22Weigl;+Bernhard\%22}, author = {Weigl, Bernhard and DE} } @patent {wu_united_2001-1, title = {United {States} {Patent}: 6297061 - {Simultaneous} particle separation and chemical reaction}, number = {6297061}, year = {2001}, month = {oct}, abstract = {This invention provides a method and apparatus for detecting the presence of analyte particles in a sample fluid also comprising larger particles, particularly blood. It exploits diffusion to provide simultaneous filtering of the larger particles and reaction of the analyte particles. A sample stream and a reagent stream join on the upstream end of a laminar flow reaction channel and flow in adjacent laminar streams. The reagents can be in solution or immobilized on a bead. The analyte particles diffuse from the sample stream into the reagent stream, leaving behind the larger particles in the residual sample stream. In the reagent stream the analyte particles react with reagent particles and form product particles, thereby creating a product stream. At the downstream end of the reaction channel, the residual sample stream and the product stream are divided. The product particles are then detected, preferably optically, in the product stream. Prior to detection, the product stream can undergo further filtering or separation, or can join a second reagent stream to form secondary product particles. This apparatus and method can be used to implement competitive immunoassays or sandwich immunoassays using enzymatically or fluorescently labeled immunoreagents. The apparatus and method can also be used to synthesize products, in which case two reagent streams join in the laminar flow reaction channel.}, url = {http://patft.uspto.gov/netacgi/nph-Parser?Sect1=PTO2\&Sect2=HITOFF\&p=1\&u=\%2Fnetahtml\%2FPTO\%2Fsearch-bool.html\&r=27\&f=G\&l=50\&co1=AND\&d=PTXT\&s1=\%22Weigl\%3B+Bernhard\%22.INNM.\&OS=IN/\%22Weigl;+Bernhard\%22\&RS=IN/\%22Weigl;+Bernhard\%22}, author = {Wu, Caicai and Weigl, Bernhard and Kenny, Margaret A. and Yager, Paul} } @patent {weigl_united_2000, title = {United {States} {Patent}: 6091502 - {Device} and method for performing spectral measurements in flow cells with spatial resolution}, number = {6091502}, year = {2000}, abstract = {A device and method for performing spectral measurements in flow cells with spatial resolution using a variable transmission optical filter having at least two areas with different optical properties. Light from a light source passes through the variable transmission filter to a flow cell containing a sample to be analyzed. The resultant light pattern is sensed by a detecting means, which analyzes the spectral properties of the sample within the flow cell.}, url = {http://patft.uspto.gov/netacgi/nph-Parser?Sect1=PTO2\&Sect2=HITOFF\&p=1\&u=\%2Fnetahtml\%2FPTO\%2Fsearch-bool.html\&r=34\&f=G\&l=50\&co1=AND\&d=PTXT\&s1=\%22Weigl\%3B+Bernhard\%22.INNM.\&OS=IN/\%22Weigl;+Bernhard\%22\&RS=IN/\%22Weigl;+Bernhard\%22}, author = {Weigl, Bernhard H. and Altendorf, Eric} } @patent {forster_united_2000, title = {United {States} {Patent}: 6134950 - {Method} for determining concentration of a laminar sample stream}, number = {6134950}, year = {2000}, month = {oct}, abstract = {A method and apparatus including programmed computers are provided for determining the viscosity of a first stream in a laminar flow and a second stream in a laminar flow, the flow rates, the centerline of the flow channel, and the position of the interface between the streams with respect to the centerline, and for calculating viscosity ratio of the first stream to the second.}, url = {http://patft.uspto.gov/netacgi/nph-Parser?Sect1=PTO2\&Sect2=HITOFF\&p=1\&u=\%2Fnetahtml\%2FPTO\%2Fsearch-bool.html\&r=33\&f=G\&l=50\&co1=AND\&d=PTXT\&s1=\%22Weigl\%3B+Bernhard\%22.INNM.\&OS=IN/\%22Weigl;+Bernhard\%22\&RS=IN/\%22Weigl;+Bernhard\%22}, author = {Forster, Fred K. and Galambos, Paul C. and Weigl, Bernhard H. and Holl, Mark R.} } @patent {weigl_united_2000-2, title = {United {States} {Patent}: 6136272 - {Device} for rapidly joining and splitting fluid layers}, number = {6136272}, year = {2000}, month = {oct}, abstract = {A device and method for introducing a second laminar fluid layer to, or removing a second laminar fluid layer from, a first laminar fluid layer are provided. Each laminar fluid layer can contain two or more side by side laminar streams. The device includes a main flow channel, and at least one tributary channel in fluid connection with a bridge channel which is in fluid connection with main flow channel. The device can be formed in a single piece of material, which can be optically transparent. Optionally, the channels can be formed in a first plate, the first and optionally the second surfaces of which are sealed to a second and optionally a third plate. The second and third plates can be optically transparent to allow for optical detection and analysis. A first laminar fluid layer is introduced into the main flow channel. If a second laminar fluid layer is to be added to the first laminar fluid layer, then the former is introduced into the tributary channel, from whence it flows into the bridge channel and then into the main flow channel, where it flows below the first laminar fluid layer and diffusionally mixes with it. Preferably, the width of the main flow channel is relatively small, so that particles in an added second laminar fluid layer diffusionally mix into the first laminar fluid layer rapidly. If a second laminar fluid layer is to be removed from a first laminar fluid layer, then the latter is split into two portions: one portion continues flowing down the main flow channel and one portion flows into the bridge channel from whence it flows into the tributary channel.}, url = {http://patft.uspto.gov/netacgi/nph-Parser?Sect1=PTO2\&Sect2=HITOFF\&p=1\&u=\%2Fnetahtml\%2FPTO\%2Fsearch-bool.html\&r=32\&f=G\&l=50\&co1=AND\&d=PTXT\&s1=\%22Weigl\%3B+Bernhard\%22.INNM.\&OS=IN/\%22Weigl;+Bernhard\%22\&RS=IN/\%22Weigl;+Bernhard\%22}, author = {Weigl, Bernhard and Zebert, Diane M. and Kenny, Margaret A.} } @patent {weigl_united_2000-1, title = {United {States} {Patent}: 6159739 - {Device} and method for 3-dimensional alignment of particles in microfabricated flow channels}, number = {6159739}, year = {2000}, month = {dec}, abstract = {The present invention provides a sheath flow module made from a first plate of material having formed therein a laminar fluid flow channel; at least two inlets, each inlet joining the laminar flow channel at a junction, the first inlet junction being wider than the second inlet junction, and an outlet from the flow channel. A second plate, e.g. a transparent cover plate, seals the module and allows for optical measurements. A first inlet allows for introduction of a first fluid into the flow channel. The first fluid is the sheath fluid. A second inlet allows for introduction of a second fluid into the sheath fluid while it is flowing through the flow channel. The second fluid is the center fluid. Because the second inlet junction is narrower than the first inlet junction, the center fluid becomes surrounded on both sides by the sheath fluid. After all fluids have been introduced and sheath flow has been achieved, the depth of the flow channel can be decreased, leading to vertical hydrodynamic focusing. Optionally, the width of the flow channel can be decreased, leading to horizontal hydrodynamic focusing. The decrease in depth and width can be gradual or abrupt. The device of the present invention can function in two modes, the sheath flow mode and the particle injector mode, depending on the relative densities of the sheath fluid, the center fluid, and any particles in either fluid.}, url = {http://patft.uspto.gov/netacgi/nph-Parser?Sect1=PTO2\&Sect2=HITOFF\&p=1\&u=\%2Fnetahtml\%2FPTO\%2Fsearch-bool.html\&r=31\&f=G\&l=50\&co1=AND\&d=PTXT\&s1=\%22Weigl\%3B+Bernhard\%22.INNM.\&OS=IN/\%22Weigl;+Bernhard\%22\&RS=IN/\%22Weigl;+Bernhard\%22}, author = {Weigl, Bernhard and Yager, Paul and Brody, James P.} } @article {229, title = {Quantitative analysis of molecular interaction in a microfluidic channel: the T-sensor.}, journal = {Anal Chem}, volume = {71}, year = {1999}, month = {1999 Dec 1}, pages = {5340-7}, abstract = {

The T-sensor is a recently developed microfluidic chemical measurement device that exploits the low Reynolds number flow conditions in microfabricated channels. The interdiffusion and resulting chemical interaction of components from two or more input fluid streams can be monitored optically, allowing measurement of analyte concentrations on a continuous basis. In a simple form of T-sensor, the concentration of a target analyte is determined by measuring fluorescence intensity in a region where the analyte and a fluorescent indicator have interdiffused. An analytical model has been developed that predicts device behavior from the diffusion coefficients of the analyte, indicator, and analyte--indicator complex and from the kinetics of the complex formation. Diffusion coefficients depend on the local viscosity which, in turn, depends on local concentrations of all analytes. These relationships, as well as reaction equilibria, are often unknown. A rapid method for determining these unknown parameters by interpreting T-sensor experiments through the model is presented.

}, keywords = {Kinetics, Models, Chemical, Spectrometry, Fluorescence}, issn = {0003-2700}, author = {Kamholz, A E and Weigl, B H and Finlayson, B A and Yager, P} } @patent {forster_united_1999-1, title = {United {States} {Patent}: 5876187 - {Micropumps} with fixed valves}, number = {5876187}, year = {1999}, month = {mar}, abstract = {Micropumps fabricated by micromachining techniques and employing fixed or no-moving-parts valves. As one aspect of the invention, a laser-assisted chemical etching technique is employed for providing smooth-walled, curved configuration necessary to obtain the desired flow characteristics of the valves that are used in conjunction with the micropump.}, url = {http://patft.uspto.gov/netacgi/nph-Parser?Sect1=PTO2\&Sect2=HITOFF\&p=1\&u=\%2Fnetahtml\%2FPTO\%2Fsearch-bool.html\&r=4\&f=G\&l=50\&co1=AND\&d=PTXT\&s1=\%22Sharma\%3B+Nigel\%22.INNM.\&OS=IN/\%22Sharma;+Nigel\%22\&RS=IN/\%22Sharma;+Nigel\%22}, author = {Forster, Fred K. and Bardell, Ronald L. and Blanchard, Alan P. and Afromowitz, Martin A. and Sharma, Nigel R.} } @patent {weigl_united_1999, title = {United {States} {Patent}: 5948684 - {Simultaneous} analyte determination and reference balancing in reference {T}-sensor devices}, number = {5948684}, year = {1999}, month = {sep}, abstract = {A reference T-sensor system is provided for detecting the presence and/or measuring the concentration of analyte particles in a sample stream. The system includes: a) a laminar flow channel; b) three or more inlet means in fluid connection with the laminar flow channel for respectively conducting into the laminar flow channel (1) an indicator stream which may include an indicator substance which indicates the presence of the analyte particles, (2) the sample stream, and (3) a reference stream, which can be a control stream and/or internal standard stream; c) wherein the laminar flow channel has a depth and/or width sufficiently small to allow laminar flow of the streams and a length sufficient to allow particles of the analyte to diffuse into the indicator stream to form a detection area; and d) outlet means for conducting the streams out of the laminar flow channel preferably to form a single mixed stream. Also provided are methods of using the device to improve accuracy and increase convenience of measuring the concentration of analytes in a sample. Monitoring reference stream(s) in laminar flow with sample stream(s) allows for calibration or for monitoring or correcting for the effects of experimental conditions which might otherwise degrade accuracy. A reference stream which serves as both a control stream and an internal standard stream is convenient and economical. The device of this invention also needs less frequent calibration than previously-known fluid analysis devices because the devices and methods of this invention provide for continuous and simultaneous quality control and internal standardization.}, url = {http://patft.uspto.gov/netacgi/nph-Parser?Sect1=PTO2\&Sect2=HITOFF\&p=1\&u=\%2Fnetahtml\%2FPTO\%2Fsearch-bool.html\&r=37\&f=G\&l=50\&co1=AND\&d=PTXT\&s1=\%22Weigl\%3B+Bernhard\%22.INNM.\&OS=IN/\%22Weigl;+Bernhard\%22\&RS=IN/\%22Weigl;+Bernhard\%22}, author = {Weigl, Bernhard H. and Holl, Mark R. and Zebert, Diane and Kenny, Margaret and Wu, Caicai} } @patent {weigl_united_1999-1, title = {United {States} {Patent}: 5972710 - {Microfabricated} diffusion-based chemical sensor}, number = {5972710}, year = {1999}, month = {oct}, abstract = {A channel-cell system is provided for detecting the presence and/or measuring the presence of analyte particles in a sample stream comprising: a) a laminar flow channel; b) two inlets in fluid connection with the laminar flow channel for respectively conducting into the laminar flow channel (1) an indicator stream which may comprise an indicator substance which indicates the presence of the analyte particles by a detectable change in property when contacted with the analyte particles, and (2) the sample stream; c) wherein the laminar flow channel has a depth sufficiently small to allow laminar flow of the streams and a length sufficient to allow particles of the analyte to diffuse into the indicator stream to the substantial exclusion of the larger particles in the sample stream to form a detection area; and d) an outlet for conducting the streams out of the laminar flow channel to form a single mixed stream.}, url = {http://patft.uspto.gov/netacgi/nph-Parser?Sect1=PTO2\&Sect2=HITOFF\&p=1\&u=\%2Fnetahtml\%2FPTO\%2Fsearch-bool.html\&r=36\&f=G\&l=50\&co1=AND\&d=PTXT\&s1=\%22Weigl\%3B+Bernhard\%22.INNM.\&OS=IN/\%22Weigl;+Bernhard\%22\&RS=IN/\%22Weigl;+Bernhard\%22}, author = {Weigl, Bernhard H. and Yager, Paul and Brody, James P. and Holl, Mark R. and Kenny, Margaret and Schutte, David and Hixson, Gregory and Zebert, M. Diane and Kamholz, Andrew and Wu, Caicai and Altendorf, Eric} } @patent {forster_united_1999, title = {United {States} {Patent}: 5974867 - {Method} for determining concentration of a laminar sample stream}, number = {5974867}, year = {1999}, abstract = {Methods and apparatuses including programmed computers are provided for determining the initial concentration of diffusible particles in a sample stream introduced into a system wherein the sample stream which contains the diffusible particles flows in adjacent laminar flow with an indicator stream containing an indicator substance capable of exhibiting an observable change at a known concentration of the diffusible particles.}, url = {http://patft.uspto.gov/netacgi/nph-Parser?Sect1=PTO2\&Sect2=HITOFF\&p=1\&u=\%2Fnetahtml\%2FPTO\%2Fsearch-bool.html\&r=35\&f=G\&l=50\&co1=AND\&d=PTXT\&s1=\%22Weigl\%3B+Bernhard\%22.INNM.\&OS=IN/\%22Weigl;+Bernhard\%22\&RS=IN/\%22Weigl;+Bernhard\%22}, author = {Forster, Fred K. and Galambos, Paul C. and Weigl, Bernhard H. and Holl, Mark R.} } @article {31, title = {Formation of high axial ratio microstructures from peptides modified with glutamic acid dialkyl amides.}, journal = {Biochim Biophys Acta}, volume = {1371}, year = {1998}, month = {1998 May 28}, pages = {168-84}, abstract = {

A growing number of amphiphiles are known to form high axial ratio microstructures (HARMs) such as the hollow cylindrical microstructures called lipid tubules. As a prelude to exploring the potential of HARMs formed from lipopeptides in controlled release drug delivery, several microstructure formation conditions were investigated. We report the preparation of several glutamic acid dialkyl amides with varying alkyl chain lengths bearing a verity of peptides (1-4 amino acids) [peptide-Glu-(NHCnH2n+1)2, n=12, 14, 16]. These surfactants have been rapidly and efficiently converted into HARMs in aqueous buffer at physiological pH and ionic strength, or in buffer containing MeOH or EtOH. Helical ribbons and tubular HARMs were produced that were stable for as long as 6 months below the phase transition temperatures of the compounds. To estimate the stability of HARMs in vivo, HARMs formed from (Pro)3-Glu(NHC16H33)2 were incubated with DOPC liposomes or fetal calf serum at 40 degreesC. HARM size and shape did not change significantly, suggesting that such lipopeptide particles can retain their morphology long enough in vivo to be useful as drug delivery vehicles.

}, keywords = {Amides, Calorimetry, Differential Scanning, Drug Carriers, Drug Stability, Glutamic Acid, Light, Lipoproteins, Liposomes, Peptides, Cyclic, Phosphatidylcholines, Scattering, Radiation}, issn = {0006-3002}, author = {Lee, K C and Lukyanov, A N and Gelb, M H and Yager, P} } @article {230, title = {Immunoregulatory mechanisms and stress hormones in psoriasis (part 1)}, journal = {Int J Dermatol}, volume = {37}, year = {1998}, month = {1998 May}, pages = {350-7}, abstract = {

BACKGROUND: In an earlier paper, the author noted that psoriatic eruptions may be produced in phases of humoral and cellular immunodeficiency and in the presence of streptococcal antigen-releasing inflammatory foci. In this study it was investigated as to whether stress hormones glucocorticoids, catecholamines) are substantially involved in the activity phases (eruptions) of psoriasis.

METHODS: During a series of investigations over two years, the following were determined for 70 chronic psoriasis patients and 50 controls: cortisol-adrenaline serum levels, polyclonal serum immunoglobulins IgM, IgG, IgA, total serum IgE, complements C3, C4, T-cells and subpopulations, streptococcal antibody titres ASO/ADNase B.

RESULTS: Phases of clinical inactivity are associated with a mechanism called immunologic regulation: elevated antibacterial titres and unremarkable findings for all other parameters. Phases of clinical activity (in 25/70 patient) showed absolutely elevated serum cortisol levels, absolutely decreased serum epinephrine levels, deficient serum IgM or IgG and IgE levels, increased C3, decreased C4 and T4:T8 ratio, and significantly elevated streptococcal titres.

CONCLUSIONS: The greatly elevated serum cortisol levels indicate that glucocorticoids are produced in excess via the pituitary adrenal axis and are significantly involved in the triggering of immunosuppressive phases (eruptions) in psoriasis.

}, keywords = {Adult, Case-Control Studies, Catecholamines, Chromatography, High Pressure Liquid, Female, Humans, Immunoglobulins, Infection, Male, Middle Aged, Psoriasis}, issn = {0011-9059}, author = {Weigl, B A} } @patent {yager_united_1998, title = {United {States} {Patent}: 5716852 - {Microfabricated} diffusion-based chemical sensor}, number = {5716852}, year = {1998}, month = {feb}, abstract = {A channel-cell system is provided for detecting the presence and/or measuring the presence of analyte particles in a sample stream comprising: a) a laminar flow channel; b) two inlet means in fluid connection with said laminar flow channel for respectively conducting into said laminar flow channel (1) an indicator stream which may comprise an indicator substance which indicates the presence of said analyte particles by a detectable change in property when contacted with said analyte particles, and (2) said sample stream; c) wherein said laminar flow channel has a depth sufficiently small to allow laminar flow of said streams and a length sufficient to allow particles of said analyte to diffuse into said indicator stream to the substantial exclusion of said larger particles in said sample stream to form a detection area; and d) outlet means for conducting said streams out of said laminar flow channel to form a single mixed stream.}, url = {http://patft.uspto.gov/netacgi/nph-Parser?Sect1=PTO2\&Sect2=HITOFF\&p=1\&u=\%2Fnetahtml\%2FPTO\%2Fsearch-bool.html\&r=39\&f=G\&l=50\&co1=AND\&d=PTXT\&s1=\%22Weigl\%3B+Bernhard\%22.INNM.\&OS=IN/\%22Weigl;+Bernhard\%22\&RS=IN/\%22Weigl;+Bernhard\%22}, author = {Yager, Paul and Weigl, Bernhard H. and Brody, James P. and Holl, Mark R.} } @patent {van_den_engh_united_1998, title = {United {States} {Patent}: 5747349 - {Fluorescent} reporter beads for fluid analysis}, number = {5747349}, year = {1998}, abstract = {The present invention provides a method and apparatus for rapid measurement of a fluid bulk analyte, requiring only microscale volumes. Several fluid bulk analytes can be measured simultaneously and, for biological samples, the cell content can also be measured simultaneously. The invention comprises reporter beads for chemical analysis of fluid bulk properties such as pH, oxygen saturation and ion content. Each reporter bead comprises a substrate bead having a plurality of at least one type of fluorescent reporter molecules immobilized thereon. The fluorescent properties of the reporter bead are sensitive to a corresponding analyte. Reporter beads are added to a fluid sample and the analyte concentration is determined by measuring fluorescence of individual beads, for example in a flow cytometer. Alternatively, reporter molecules which change absorbance as a function of analyte concentration can be employed.}, url = {http://patft.uspto.gov/netacgi/nph-Parser?Sect1=PTO2\&Sect2=HITOFF\&p=1\&u=\%2Fnetahtml\%2FPTO\%2Fsearch-bool.html\&r=38\&f=G\&l=50\&co1=AND\&d=PTXT\&s1=\%22Weigl\%3B+Bernhard\%22.INNM.\&OS=IN/\%22Weigl;+Bernhard\%22\&RS=IN/\%22Weigl;+Bernhard\%22}, author = {van den Engh, Ger and Weigl, Bernhard H.} } @article {32, title = {Formation of high-axial-ratio-microstructures from natural and synthetic sphingolipids.}, journal = {Chem Phys Lipids}, volume = {88}, year = {1997}, month = {1997 Aug 8}, pages = {21-36}, abstract = {

Amphiphiles that form high-axial-ratio-microstructures (HARMs) are being considered as novel materials for controlled release of drugs and other biologically functional molecules. HARMs consisting of tubules, ribbons, solid rods and helices are formed from sphingolipids by addition of water to a solution of amphiphile in DMF. Single molecular species of galactocerebroside (GalCer) containing long unsaturated fatty acid chains or natural GalCer containing mixed-length, non-hydroxy fatty acids (NFA-GalCer) or alpha-hydroxy fatty acids (HFA-GalCer) form cylindrical structures. In contrast, single molecular species of GalCer containing long saturated fatty acids form ribbons and helices. GalCer HARMs are typically under 100 nm in diameter and have lengths of several microns. The importance of the amide of GalCer for HARM formation was evaluated using psychosine, which forms solid fibers, whereas sphingosine and an analog of GalCer in which the amide is reduced to a secondary amine form amorphous aggregates. Single molecular species of ceramide containing long unsaturated fatty acid chains form cylindrical structures, whereas those with long saturated fatty acids form ribbons and helices. Short chain saturated ceramide also forms cylindrical structures. GalCer analogs with N-acetyl-glycine in place of the galactose form fibers whereas those with N-acetyl-proline yield amorphous material. The N-acetyl-proline-containing amphiphile can de doped into pure GalCer or NFA-GalCer without perturbing tubule formation.

}, keywords = {Amides, Amino Acids, Calorimetry, Differential Scanning, Ceramides, Delayed-Action Preparations, Fatty Acids, Galactosylceramides, Sphingolipids}, issn = {0009-3084}, author = {Goldstein, A S and Lukyanov, A N and Carlson, P A and Yager, P and Gelb, M H} } @article {231, title = {Capillary waveguide optrodes: an approach to optical sensing in medical diagnostics.}, journal = {Appl Opt}, volume = {35}, year = {1996}, month = {1996 Jul 1}, pages = {3426-31}, abstract = {

Glass capillaries with a chemically sensitive coating on the inner surface are used as optical sensors for medical diagnostics. A capillary simultaneously serves as a sample compartment, a sensor element, and an inhomogeneous optical waveguide. Various detection schemes based on absorption, fluorescence intensity, or fluorescence lifetime are described. In absorption-based capillary waveguide optrodes the absorption in the sensor layer is analyte dependent; hence light transmission along the inhomogeneous waveguiding structure formed by the capillary wall and the sensing layer is a function of the analyte concentration. Similarly, in fluorescence-based capillary optrodes the fluorescence intensity or the fluorescence lifetime of an indicator dye fixed in the sensing layer is analyte dependent; thus the specific property of fluorescent light excited in the sensing layer and thereafter guided along the inhomogeneous waveguiding structure is a function of the analyte concentration. Both schemes are experimentally demonstrated, one with carbon dioxide as the analyte and the other one with oxygen. The device combines optical sensors with the standard glass capillaries usually applied to gather blood drops from fingertips, to yield a versatile diagnostic instrument, integrating the sample compartment, the optical sensor, and the light-collecting optics into a single piece. This ensures enhanced sensor performance as well as improved handling compared with other sensors.

}, issn = {0003-6935}, doi = {10.1364/AO.35.003426}, author = {Lippitsch, M E and Draxler, S and Kieslinger, D and Lehmann, H and Weigl, B H} } @article {232, title = {Optical triple sensor for measuring pH, oxygen and carbon dioxide.}, journal = {J Biotechnol}, volume = {32}, year = {1994}, month = {1994 Feb 14}, pages = {127-38}, abstract = {

A triple sensor unit consisting of opto-chemical sensors for measurement of pH, oxygen and carbon dioxide in bioreactors is presented. The pH and the CO2 sensor are based on the color change of a pH-sensitive dye immobilized on a polymeric support. The resulting changes in absorption are monitored through optical fibers. The oxygen sensor is based on the quenching of the fluorescence of a metal-organic dye. All three sensors are fully LED compatible. The sensitive membranes consist of plastic films and can be stored and replaced conveniently. The sensors are sterilizable with hydrogen peroxide and ethanol. In addition, the pH sensor is steam sterilizable. Accuracy, resolution and reproducibility fulfill the requirements for use in biotechnological applications. Calibration procedures for each sensor are presented. The working principle and the performance of all three sensors are described, with particular emphasis given to their application in bioreactors.

}, keywords = {Carbon Dioxide, Hydrogen-Ion Concentration, Oxygen}, issn = {0168-1656}, author = {Weigl, B H and Holobar, A and Trettnak, W and Klimant, I and Kraus, H and O{\textquoteright}Leary, P and Wolfbeis, O S} }