Microarray Chip and Method for Simultaneous and Highly Consistent Electroporation of Multiple Cells of Different Sizes

Cell electroporation is an importantcell manipulationtechnologyto artificially transfer specific extracellular components into cells.However, the consistency of substance transport during the electroporationprocess is still an issue due to the wide size distribution of thenatural cells. In this study, a cell electroporation microfluidicchip based on a microtrap array is proposed. The microtrap structurewas optimized for single-cell capture and electric field focusing.The effects of the cell size on the cell electroporation in the microchipwere investigated through simulation and experiment methods usingthe giant unilamellar vesicle as the simplified cell model, and anumerical model of a uniform electric field was used as a comparison.Compared with the uniform electric field, a lower threshold electricfield is required to induce electroporation and produces a highertransmembrane voltage on the cell under a specific electric fieldin the microchip, showing an improvement in cell viability and electroporationefficiency. The larger perforated area produced on the cells in themicrochip under a specific electric field allows a higher substancetransfer efficiency, and the electroporation results are less affectedby the cell size, which is beneficial for improving substance transferconsistency. Furthermore, the relative perforation area increaseswith the decrease of the cell diameter in the microchip, which isexactly opposite to that in a uniform electric field. By manipulatingthe electric field applied to the microtrap individually, a consistentproportion of substance transfer during electroporation of cells withdifferent sizes can be achieved.

Automated summary

This study proposes a microfluidic chip for cell electroporation based on a microtrap array, which optimizes the microtrap structure for single-cell capture and electric field focusing. Compared with a uniform electric field, a lower threshold electric field is required to induce electroporation and produces a higher transmembrane voltage on the cell in the microchip, showing an improvement in cell viability and electroporation efficiency. Furthermore, the larger perforation area produced on the cells in the microchip under a specific electric field allows a higher substance transfer efficiency and is less affected by the cell size, benefiting the consistency of substance transfer.