Microfluidic single-cell array platform enabling week-scale clonal expansion under chemical/electrical stimuli

Single-cell culture represents the most straightforward method for investigating cellular heterogeneity. In this paper, we present a novel microfluidic platform that can individually array and culture hundreds of cells under chemical and electrical stimuli for week-scale characterization. Single cells can be deterministically and gently captured in a microchamber array on the proposed platform. The size of the microchamber can be adjusted to fit different cell culture times, and this characteristic enables remarkable scalability. Transparent indium tin oxide microelectrodes were integrated with the single-cell array platform for on-chip electrical stimuli. The platform exhibited nearly 90% single-cell efficiency and facilitated week-scale clonal expansion of different types of single cells. Chemical and electrical stimuli affected proliferation and differentiation of MC 3T3-E1 cells were examined on the chip prototype that contained 416 (32 rows × 13 columns) microchambers, and each microchamber had 1 mm diameter. By tracking clonal expansion of cells under chemical/electrical stimuli for relatively long periods, the proposed platform can facilitate the screening of the cell subpopulation with a favorable growth phenotype for drug testing and cell therapy.