Preparation And Characterization Of Nano-magnetic Cationic Liposomes

Objective: To make nano-magnetic cationic liposomes which have good properties of drug carrying, magnetic targeting and biocompatibility . To discuss how to make liposomes, cationic liposomes, nano-magnetic cationic liposomes morphology, particle size and the impact of Zeta electric potential .Therefore,to determine the best ratio and the best technology.Methods: We used the film dispersion method and RP-evaporation method in producing liposomes, the two methods of preparation of liposomes and particle morphology were compared, and studied the effect of ultrasonic power and concentration impact on liposomes. We used Cationic lipid (DC2chol/DOPE) as a raw material to produce cationic liposomes and nano-cationic liposomes which had magnetic property, also detected their morphology, size, Zcta electric potential, the interaction between DNA with them, and cell toxicity testing. We used agarose gel electrophoresis method to research the nano-magnet cationic liposomes complex reaction between DNA with them. MTT assay evaluated nano-magnet cationic liposomes cell toxicity.Results:The concentration of liposomes was 0.25-0.5 mg / ml, which had the best shape. The size of liposome particle and the distribution of particle size distribution decreased accompanying with the ultrasonic power increased. The size of liposomes produced by the film scattered was slightly bigger than that of liposomes produced by RP-evaporation. By analyzing particle size and TEM indicates that the addition of cationic lipid molecules would not increase the size of liposomes, cationic liposomes and nano-magnetic cationic liposomes had spherical morphology, the average size of particle ranged from 95 to 130-nm. Zeta electric potential test showed that the addition of cationic lipid molecules enabled the surface of liposomes with MMH. Gel electrophoresis analysis showed that the ratio of nano-magnet cationic liposomes to DNA was 2:1, and the DNA could completely shape into stable complexes. MTT assay showed that the toxicity of nano-magnetic cationic liposomes as gene vector was relatively lower.Conclusions: The non-magnetic cationic liposomes and magnetic cationic liposomes which made in this study can be screened as higher efficiency of transfection and lower cytotoxicity genetic carrier.