Microfluidic Devices for High Throughput Cell Sorting and Chemical Treatment

Separation by size is a fundamental analytical and preparative technique in biology, medicine, and chemistry. Deterministic lateral displacement (DLD) arrays are mi-crofluidic devices capable of high-precision particle sorting based on size. In this thesis, we will discuss improvements in the functionality of DLD arrays and several new applications. We’ll first discuss a methodology for performing sequential on-chip chemical treatment by using the DLD array to direct particles in the “bumping” trajectory across co-flowing reagent streams and demonstrates this technique with platelet labeling and washing and E. Coli lysis and chromosomal separation. We then discuss a deterministic microfluidic ratchet that could separate particles in an intermediate size range using a DLD array with triangular posts in an oscillating flow. We then extended this idea of using triangular posts in DLD arrays to continuous-flow operation and showed significant performance enhancements over arrays with circu-lar posts when the triangle vertex is used as the displacement edge. Taking this idea of increasing device throughput to the next step, we developed a highly parallelize