FIG. 5.

DEP significantly effects the capture probability of cells in the obstacle array. Here, the percent change in simulated $P_{\text{capture}}$—i.e., $(P_{\text{capture}\hspace{0.17em}\mathrm{w}/\hspace{0.17em}\text{DEP}}-P_{\text{capture}\hspace{0.17em}\mathrm{w}/\mathrm{o}\hspace{0.17em}\text{DEP}})/(P_{\text{capture}\hspace{0.17em}\mathrm{w}/\mathrm{o}\hspace{0.17em}\text{DEP}})$—is shown for pancreatic cancer cells and PBMCs for two independent simulations, one driven at 50 kHz and another at 200 kHz, in an array with Δ = 2 μm. The simulations show that the capture of contaminating PBMCs is reduced by greater than 99% at 200 kHz (from 0.16 to 0.001); simultaneously, the capture of target pancreatic cancer cells is increased by 370%–450% (from 0.03–0.10 to 0.14–0.55, based on cell line). Although the absolute capture probability for pancreatic cancer cells would be greater at a larger offset, the improvement in sample purity (i.e., the large reduction in P_capture for PBMCs) predicted using DEP at a small offset outweigh a small decrease in capture efficiency, especially for applications such as single-cell genetic analyses.