Micro-fabricated fluorescence-activated cell sorter

We demonstrate a high sensitivity, high throughput microfabricated cell sorting device with the integrated piezoelectric actuator and optofluidic waveguide on a chip. For automated sorting, field-programmable-gate-array (FPGA) embedded real time control loop system is built. The sorting is performed under high flow rate (~10 cm/sec), and the sorting system can achieve a high throughput (> 1 kHz) with high purity. Moreover, to enhance its sensitivity, Teflon AF coated liquid core waveguide (LCW) structure is demonstrated. Teflon AF has a lower refractive index (n=1.31) than water (n=1.33) and forms the cladding layer of the LCW. Incident light is confined and guided along the Teflon AF coated fluidic channel, and interact with samples flowing along the same channel. This enables flexible device design and gives high sensitivity to the fluorescence detection system. The preliminary results demonstrate sorting fluorescent beads at a sorting efficiency of ~70% with no false sorting.