EFFECT OF CATIONIC LIPOSOME COMPOSITION ON IN-VITRO CYTOTOXICITY AND PROTECTIVE EFFECT ON CARRIED DNA

Positively charged liposomes were prepared by using three different ca tionic surfactants, namely cetyl-trimethyl-ammonium bromide (CTAB), di dodecyl-dimethyl-ammonium bromide (DDAB(12)) and dioctadecyl-dimethyl- ammonium bromide (DDAB(18)). A study of the parameters influencing the in vitro toxicity of cationic liposomes on cultured cell lines was pe rformed, demonstrating the lower cytotoxicity of DDAB(18)-containing l iposomes. In addition, the stability of lambda DNA complexed to cation ic liposomes after exposure to serum exo- and endonucleases was evalua ted. Our results indicated that DDAB(12) and DDAB(18) liposomes are ab le to efficiently protect DNA from degradation, thus representing a po tential approach to deliver nucleic acid in vivo.