A Microfluidic System for Affinity Reagent Generation and Assay Development for High-Throughput Biomarker Validation

Protein biomarkers are finding increasing application in Force Health Protection and health surveillance. However, very few biomarkers have been verified and validated to-date. This deficiency can primarily be ascribed to the scarcity of reagents (affinity probes). There is a need for assays to measure biomarker candidates, which must be accompanied by the development of reagents for detection. Currently, no miniaturized system to develop reagents in a cost-effective, high-throughput format is commercially available. The goal of the proposed research is to develop a microfluidics-based high-throughput reagent generation platform using capillary electrophoresis (CE) to enable the discovery and directed evolution of molecular probes from combinatorial libraries using an in vitro protein selection technique. The platform will be adapted to develop immunoassays using the probes selected. Key benefits include faster screening, reduced reagent consumption (cost savings), thermostable probes, and automation. In Phase I, we successfully demonstrated the generation of high quality combinatorial probe libraries using innovative protein engineering strategies. Proof-of-principle of the microfluidic screening concept was also established. In Phase II, the microfluidic system will be refined and used to develop reagents for selected biomarker targets, including those of interest to USACEHR. A multidisciplinary team with proven expertise in microfluidics, protein engineering, and device development has been assembled.