Abstract: In 2006, we showed the first true evidence of a sample-in/answer-out microfluidic technology that could detect Bacillus anthracis in infected mouse blood and Bordetella pertussis in a human nasal swab; DNA extraction, PCR amplification of target sequences and separation/detection was complete in less than 30 minutes. This development seeded the possibility for doing short tandem repeat (STR) profiling in human DNA – this is the DNA basis for human identification used by the justice system, and is technology being commercialized by a UVA start-up. We have since exerted effort on diagnostic applications with the focus of simplifying the technology. We are exploring novel, more rational approaches to fluid flow control on microdevices, both passive (with UC-SB) and active. The latter involves centrifugally-driven flow systems fabricated from polyethylene (overhead transparencies) with architecture defined by laser printing and ablation. These present an innovative means of creating functional microdevices that are cost-effective (<$1USD) amenable to simple colorimetric assays. Finally, and time allotted, we will discuss a simple DNA detection modality we have discovered that is less about microfluidics and more about microscale bead aggregation that occurs under conditions with the appropriate bead surface chemistry and surrounding environment. We show that these can be used for generic DNA quantification and extrapolated to cell counting for white cells in whole blood and even CD4+ lymphocytes. When oligos are appended to the bead surface, specific DNA sequences induce aggregation, presenting some interesting possibilities for mutation detection of endogenous DNA but also applicable to detecting infectious agents.
Bio: James Landers is Professor of Chemistry, Professor of Mechanical Engineering at the University of Virginia, and an Associate Professor of Pathology at the University of Virginia Health System. James received his Bachelor of Science degree in Biochemistry with a minor in Biomedicine at the University of Guelph in Ontario (Canada) in 1984. He earned his Ph.D. in Biochemistry from the same department in 1988. After a one-year post-doctoral fellowship at the University of Toronto’s School of Medicine, he was awarded a MRC Fellowship to study cancer biology at the Mayo Clinic. After the post-doc, he launched and directed the Clinical Capillary Electrophoresis Facility in the Department of Lab Medicine and Pathology at Mayo developing clinical assays using capillary electrophoretic technology. After two years as a Professor of Analytical Chemistry at the University of Pittsburgh, he forayed into analytical microfluidic systems with the goal of developing the next generation molecular diagnostics platform. He has published more than 200 papers in peer-reviewed journals, 22 book chapters and edited three editions of the CRC Press Handbook of Capillary Electrophoresis. A 2006 PNAS paper showed the generation of one of the first sample in-answer out microdevices for genetic analysis and this work led to his receiving of the 2008 Association for Lab Automation ‘Innovative Technology of the Year’ Award. He is currently the Microfluidics Editor for Analytica Chimica Acta, a member of the Analytical Chemistry Editorial Advisory Board, and member of the Chemical and Biological Microsystems Society.