Assembly of Plasmid DNA into Liposomes After Condensation by Cationic Lipid in Anionic Detergent Solution

A novel strategy to prepare negatively charged and small DNA-containing liposomes after condensation of plasmid DNA by a cationic lipid in deoxycholate micelle environment is described. The average diameter of resulting complexes was 62±8 nm. DNA-containing liposomes were then prepared by dialysis. The shape of the resulting liposomes was spherical. The average diameter and the surface charge of the liposomes were 86±6 nm and −24±3 mV, respectively. The plasmid DNA inside liposomes remained in a supercoiled form after incubation with DNase.