To clarify physicochemical properties of the pDNA/AF-liposomes, we determined the particle sizes and ζ-potential values of the pDNA/γ-CyD/AFliposomes at the charge ratio of 1.6. The mean diameter of the pDNA/γ-CyD/AF-liposomes was smaller than that of pDNA/AF-liposomes or pDNA/HP-γ-CyD/AF-liposomes (Table 2) . Meanwhile, the ζ-potential values of pDNA/AFliposomes, pDNA/γ-CyD/AF-liposomes, and pDNA/HP-γ-CyD/AF-liposomes were almost comparable ( Table 2 ). These results indicate that γ-CyD reduced the particle size of AF-liposomes but did not change the ζ-potential value of pDNA/CyD/AF-liposomes. The charge ratio of AF-liposome/pDNA was 1.6. γ-CyDs were added to AFliposome suspension before freeze-drying. The concentrations of γ-CyDs were 1 μM/μM lipids. The encapsulation ratios of pDNA were determined using Picogreen assay. The encapsulation ratios of γ-CyDs were determined by an anthrone-sulfuric acid method. Each value represents the mean ± SEM of 3 experiments. * P < .05 versus without CyD.