“…[3][4][5] Electro-transfection is also termed as electroporation, which creates the transient permeabilization of the plasma membrane with temporary pores, due to high local transmembrane potential induced by an external electric field. However, existing electrotransfection systems, including microfluidic platforms and commercial benchtop systems, are only able to study monolayer cell suspensions in vitro, which is incapable of clinical translation within in vivo tissue microenvironment [6][7][8][9][10][11][12][13] . It has been well documented that cells growing in two-dimensional (2D) culture system significantly differ from living threedimensional (3D) tissues in terms of cell morphology, functions, cell-to-cell communications, and cell-to-matrix adhesions.…”