The Systematic Optimization of Square Wave Electroporation for Six Commonly Used Human Cell Lines

Abstract

During cellular electroporation, the formation of transient pores allow for the diffusion of innately impermeable molecules. The diversity of cell and membrane structure results in unique properties with respect to sensitivity to electric fields. The growing use of human cell lines in biomedical research and technology has led to a demand for protocols that can effectively and economically perform electroporation. We electroporated six human cell lines using a fluorescent reporter to investigate the effects of pulse electric field strength, pulse duration, and DNA concentration during electroporation. It was found that the cell lines all responded to electric field strengths within 400-950V/cm with viability decreasing with increasing voltage. It was also observed that the concentration of DNA used directly impacts transfection efficiency and cell viability as well. To better characterize square wave electroporation, we adopted a model where the pulse is described by its energy density (J/L) with respect to the sample buffer volume. It was determined that the key electrical characteristics of electroporation can be generalized with this value to provide a simplified measure of pulse intensity. The resulting analysis was consistent with other models, indicating cell type specific optimal electrical and DNA concentrations.