Human mammalian cell sorting using a highly integrated micro-fabricated fluorescence-activated cell sorter (μFACS)

We demonstrate a high performance microfabricated FACS system with highly integrated microfluidics, optics, acoustics, and electronics. Single cell manipulation at a high speed is made possible by the fast response time (∼0.1 ms) of the integrated PZT actuator and the nozzle structure at the sorting junction. A Teflon AF-coated optofluidic waveguide along the microfluidic channel guides the illumination light, enabling multi-spot detection, while a novel space-time coding technology enhances the detection sensitivity of the μFACS system. The real-time control loop system is implemented using a field-programmable-gate-array (FPGA) for automated and accurate sorting. The μFACS achieves a high purification enrichment factor: up to ∼230 fold for both polystyrene microbeads and suspended human mammalian cells (K562) at a high throughput (>1000 cells s −1 ). The sorting mechanism is independent of cell properties such as size, density, and shape, thus the presented system can be applied to sort out any pure sub-populations. This new lab-on-a-chip FACS system, therefore, holds promise to revolutionize microfluidic cytometers to meet cost, size, and performance goals. The novel high fluorescence detection strategy called "space-time coding" technique and the on chip PZT actuator realized a lab-on-a-chip sorter with high purity and high throughput.