Pneumatic microfluidics-based multiplex single-cell array

Large-scale single-cell arrays are urgently required for current high-throughput screening of cell function and heterogeneity. However, the rapid and convenient generation of large-scale single-cell array in a multiplex and universal manner is not yet well established. In this paper, we report a simple and reliable method for the generation of a single-cell array by combining pneumatic microvalve arrays (PμVAs) and hydrodynamic single-cell trapping sites in a single microfluidic device. The PμVAs, which can be precisely controlled by actuated pressures, were designed to guide multiple types of cells being trapped in the corresponding single-cell trapping sites located in the fluidic channel. According to the theoretical demonstration and computational simulation, we successfully realized a multiplex single-cell array with three different types of cells by a step-by-step protocol. Furthermore, the analysis of cellular esterase heterogeneity of the three types of cells was concurrently implemented in the device as a proof-of-concept experiment. All the results demonstrated that the method developed in the current study could be applied for the generation of large-scale single-cell array with multiple cell types, which would be also promising and helpful for single-cell-based high-throughput drug test, multipurpose immunosensor and clinical diagnosis.