Basic Information

Abstract Number: 1770-3     Author Name: Robert T Kennedy Affiliation: University of Michigan Session Title: Young Investigator Award from Subdivision on Chromatography and Separation Chemistry of the Analytical Chemistry Division of the ACS Event Type: Award Event Title: High Throughput Electrophoresis Using Droplets and Microfluidics Presider(s): Bidlingmeyer, Brian A Start Time: 09:20 AM ( Slot # 5 ) Date: Wednesday, March 3rd, 2010 Location: 300 Keywords: Bioanalytical, Capillary Electrophoresis, Drug Discovery, Enzyme Assays

Abstract Content

The throughput of electrophoretic analysis has typically been improved using two main approaches. Miniaturization of electrophoresis channels allows application of high electric fields over short distances to reduce separations times to a few seconds or less. This approach has been mostly used for “sensing” applications where concentration of separated and detected substances is monitored over time. Advances in fabrication and detection technology have also allowed development of systems with parallel channels for improved throughput. This latter technology has mostly been applied to genetic analysis. We have combined rapid separations on microchips with parallel architectures (up to 48 channels) for a substantial improvement in overall throughput, up to ~17,000 assays/hour. This high throughput allows a variety of new applications. In one example, 36 individual enzymatic reactions are monitored at 10 s intervals using rapid, serial electrophoresis in parallel. Another application is to monitor cellular secretions from discrete tissue samples over time in parallel. We have shown the utility of a 15-channel system for monitoring insulin secretion from 15 individual islets of Langerhans. Both of these cases monitor concentration changes that are generated within sample chambers on the chip. A more difficult problem is introducing discrete samples to a chip for high-throughput analysis. We are exploring use of segmented flows, where aqueous samples are manipulated as droplets within an immiscible carrier fluid, as a method of preparing and introducing discrete samples to electrophoretic channels. This system may have application to high-throughput screening.