High-throughput inertial microfluidic platforms for single-cell mechanotyping and intracellular molecule delivery

Abstract

Second, the iMCS platform can be expanded to inertial microfluidic cell hydroporator (iMCH) for a high-throughput and single-step intracellular molecule delivery, providing emerging opportunities for single-cell engineering. Briefly, rapid cell mechanical deformation and fluid shearing upon cell-wall collision at a T-junction create transient membrane openings that facilitate passive diffusion of biomaterials into the cell cytosol. Unlike traditional delivery methods that rely on external fields, exogenous materials, endocytosis, or chemical modification of target molecules, our approach provides a faster and reliable process with lower costs. Using this method, various biomolecules (CRISPR-Cas9, plasmid DNA, DNA nanostructures, siRNA, and dextran) have been successfully delivered to different cell lines with high delivery efficiencies and minimal effect on cell viability. Finally, to further simplify the operation of the device, a sheathless microfluidic platform with extensional flow region has been developed to stretch cells at the stagnation point, where the compression and shear forces generate transient membrane discontinuities that facilitate passive diffusion of external materials into the cell cytoplasm. This platform has achieved highly efficient delivery of various materials into a wide range of cell types.