Single cell separation by using accessible microfluidic chip

Here we proposed a novel device named CACS (Convective Accumulation-based Cell Separator) system that is composed of a cell-trapper unit with accessible (open-structured) microfluidic device and a cell-picker device with high aspect ratio PDMS pillars. Utilizing this systematic instrument, we demonstrated proof-of-concept for cell separation through the process of (1) single cell trap in a well (2) single cell picking by pillar-based tweezers and (3) cell recovery. The optimized system for mammalian cells had enabled us to trap-in and pick-up target cells in 100% efficiency as far as tested. Moreover, picked cells showed 74.5% viability, as a result of a less-invasive cell separation technique. Furthermore, a series of different PDMS pillars indicated their varied efficiency in pick-up and recovery steps. We also found out that the aspect ratio of PDMS pillar is critical for tweezing a cell of interest. To improve on the performance of CACS system, further tuning is necessary, especially on the recovery unit for achieving an efficient and damage-free separation. Though CACS system shows low-throughput at this moment, its simplicity is applicable for any cell type by optimizing each pipeline.