Flow-through electroporation of mammalian cells in decoupled flow streams using microcapillaries

We report on reversible electroporation of cells in a flow-through microfluidic device, whereby the required electric field is delivered through a set of integrated microcapillaries between a centre stream of cells and side streams of liquid electrolytes. The electrolytes are applied with a sine wave voltage and cells flow by the microcapillary openings encounter a burst of ac field with a duration and strength determined by their average speed and spatial proximity to the microcapillary openings, respectively. Effectiveness of the approach is presented through numerical simulations and empirical results on electroporation efficiency and cell viability against various flow rates (exposure time to the field) as well as frequencies and root-mean-square (rms) intensities of the field. High frequencies (80-400 kHz) and high intensities (e.g., 1.6 kV/cm, rms) are identified with increased electroporation efficiency 61% and viability 86% on average. These results suggest that the device demonstrated here with a simple design and robust operation offers a viable platform for flow-through electroporation.