Optimization of electrotransfection conditions of mammalian cells with different biological features

We introduced eukaryotic expression plasmid pEGFP-N1 encoding green fluorescent protein (GFP) genes into cells with different biological features through electroporation. The effects of conditions, including voltage, capacitor flow, pulse cycle, DNA dosage and buffer, on transfection efficiency were investigated based on fluorescent microscopy and posttransfection survival rate of cells by staining with trypan blue. Better electrotransfection outcomes were achieved in the following epithelial cells: Vero cells at 300 V/850 μF, PK15 cells at 300 V/500 μF, MDCK cells at 200 V/600 μF, F81 cells at 200 V/500 μF, cancer cells MB49 at 300 V/400 μF, Hela cells at 200 V/450 μF, HF-29 cells at 300 V/800 μF and B16F1 cells at 200 V/650 μF. Among fibroblast cells, better electrotransfection was achieved in BHK21 cells at 300 V/600 μF and ST cells at 200 V/750 μF. RPMI-1640 medium without antibiotics and serum demonstrated higher electrotransfection efficiency and cell survival rate than other cell culture media as electroporation buffer. Our findings further prove that electroporation transfection is an effective method for genetic transfection. Cells with different biological features require varying transfection conditions to obtain higher transfection efficiency of target genes.