Triangular microwell for single cell trapping and short-term culturing: Cellular study and analysis of Leukemia cell line

Microfluidic system is a single cell analysis (SCA) platform which is useful for cellular biological study. However, the system still needs further development and improvement for a complete high-throughput single cell analysis. The purpose of this study was to design and develop a microfluidic device for trapping and culturing single cells of human leukemia cell line. Trapping achievement and short-term culture capability were also evaluated. Polydimethylsiloxane (PDMS) microfluidic device consisted of two layers, one of which was a main channel with a dimension of 5 mm wide, 15 mm long, 70 & mu;m high; and an array of 40 & mu;m equilateral triangular microwells with 30 & mu;m deep arranged in downward oblique direction. Trapping efficacy results were about 70.8% for single cells. The effects of different cell densities on cell trapping rates showed that the increment of cell density reduced the single cell trapping capability, and the trapping method was not harmful to the cells. Potential short-term culture of single cell trapping examined by Trypan blue dye assay and Calcein AM/EthD-1 fluorescent staining revealed 80% and 75% of cellular viability after 24 and 48 h of incubation, respectively. In summary, our developed PDMS microfluidic device succeeded in single cell trapping pattern and short-term culturing of leukemia cell line single cells.