2.4. Determination of Zeta potential, particle size, and polydispersity index of liposomes

Values of the Zeta potential of liposomes indirectly reflect vesicle surface net charge and can therefore be used to evaluate the extent of interaction of the liposomal surface cationic charges with the anionic charges of DNA. The average particle size and the polydispersity of the particle-size distribution of the liposomes were determined by Zeta sizer. Zeta potential is an indirect measurement of the vesicle surface charge, and it can be used to evaluate the extent of interaction of the liposomal surface cationic charges with the anionic charges of DNA [2], [3], [4]. To check the stability of the liposomes, size and potential of the liposomes were checked every 4 days.