Published online by Cambridge University Press: 21 February 2011
Cationic gelatin was evaluated as a non-viral vector for cell transfection. We hypothesized that cationic gelatin would be a nontoxic alternative to already existing viral and non-viral cationic vectors. Cationic gelatin was synthesized by modifying gelatin with hexanediamine. Complexation of cationic gelatin with psv-β-gal plasmid caused an electrophoretic mobility shift of the plasmid. Cationic gelatin/DNA complexes were optimized in terms of transfection efficiency in CHODUK XB1 and COS 7 cell lines. Maximal gene expression for both cell types occurred in serum free medium with chloroquine (100 μM) at cationic gelatin/DNA ratios of approximately 2 and 7. In comparison with DEAE dextran, polylysine and Lipofectamine, cationic gelatin was the most efficient in transfecting COS 7 cells, with up to 18% cells transfected. In a dye reduction cytotoxicity assay, cationic gelatin caused < 5% of cells to become nonviable at a concentration of 100 μg/ml, while the other transfection reagents tested at the same concentration caused 25–100% of cell death. These results suggest that cationic gelatin holds promise as an effective vehicle for gene delivery to mammalian cells.