Effect of Acyl Chain Length of Spermine Derivatives on Transfection Efficiency

Abstract

In this study, cationic liposomes prepared from egg phosphatidylcholine (PC) and novel spermine-based cationic lipids at a molar ratio of 5:1 were formulated. The chemical structures of these cationic lipids consisted of spermine head group and four hydrocarbon tails with differences in acyl chain (C14, C16 and C18). The effects of acyl chain and weight ratio of liposomes to DNA on transfection efficiency and cytotoxicity were investigated on a human cervical carcinoma cell line (HeLa cells) using the pDNA encoding green fluorescent protein (pEGFP-C2). The results from agarose gel electrophoresis illustrated that all cationic liposomes were able to condense with pDNA. The transfection efficiency of these cationic liposomes was in the following order: C18 (3,497±120 cells/cm2) > C14 (809±52 cells/cm2) > C16 (91±5 cells/cm2). The highest transfection efficiency was observed in the formulation of cationic liposomes with C18 tail at weight ratio of 15. In cytotoxicity studies, all formulations showed low cytotoxicity. In conclusion, these cationic liposomes containing novel cationic lipids (C18), showed promising potential as a gene carrier by efficient DNA condensation and mediated higher level of gene transfection.