Recent advances in microfluidic cell sorting systems

Effective and high-throughput cell sorting are critical technologies in single cell analysis in biology, medicine and clinical applications. Especially for single cell analysis requiring high accuracy, multiple sorting mechanisms are required, and they need to be well organized into a system based on the sorting ability. Therefore, we classify most recent methods of microfluidic cell sorting as precise or large amount sorting methods based on the ability for sorting the number of cells. Precise sorting applies an instantaneous force (e.g. acoustic, electric, optical, and jet force) to displace cells a short distance to isolate them one by one with relatively high accuracy. Large amount methods use a continuous force (e.g. acoustic, electric, magnetic and passive force) to arrange, separate and purify cell populations with relatively high-throughput. By combining precise sorting and large amount sorting methods, it is possible to achieve a high-accuracy sorting system with high-throughput. Therefore, in this review, we summarized merits and demerits of these advanced technologies of sorting (focusing on those devices in the last five years that have features of high-throughput, portability and high efficiency) to suggest some suitable combinations of large amount and precise sorting methods; then we discussed the direction of single cell sorting and the prospects of the combined microchips.