Integrated DEP presorting and wireless electrode array for high-throughput selective single-cell isolation

Rare cell heterogeneity significantly impacts diagnosis, prognosis, therapeutic options and responses, particularly in diverse diseases like cancer. While single-cell analysis is the most effective route, isolating cells individually with high selectivity, purity, efficiency and throughput remains a major challenge. Thus, we present a unified platform coined "SC-DEPOT" to perform all analytical steps from selective isolation from a mixture of cells to parallel single-cell analysis. The platform integrates three sequential modules - one hydrodynamic and two DEP-based - to independently execute distinct and complementary functions. First, the hydrodynamic module focuses all cells towards the channel centerline. Then by DEP, slanted interdigitated electrodes selectively redirect target cells to the channel walls, where they are finally captured in cell-sized micropockets by insulator-based DEP (iDEP). This final stage builds on our previously reported iDEP device, which isolates cells in nanoliter-scale chambers - which are addressed by "wireless" bipolar electrodes (BPEs) - to facilitate individual analysis. The added two preceding steps enhance sample purity to 96% and enable an eightfold increase in channel width compared to a previous limitation of 100 μm. This result is important because it yields an eight-fold to sixteen-fold enhancement in volumetric throughput for samples comprising a mixture of cell types or only one cell type, respectively. The final iDEP module isolates single cells at 94% efficiency and transfers them into the sealable chambers at 92% efficiency. This combination of high throughput and gentle, extended capture from highly concentrated backgrounds expands the utility of the SC-DEPOT device in clinical workflows.