4.2.2. Characterization of Liposomal Size and Zeta Potential Distributions Using Dynamic and Electrophoretic Light Scattering

Both particle size and zeta potential distributions were measured using a Zetasizer Nano ZS (Malvern Instruments, Malvern, UK) equipped with a HeNe laser (633 nm). Scattered laser light was collected at a constant angle of 173°. Prior to measurements, liposome stock solutions were diluted 1/50 with purified and filtrated water (Milli-Q Gradient A10, Merck Millipore, Darmstadt, Germany). All measurements were performed at 20 °C and repeated three times at 1 min intervals. Data were collected from three independently prepared samples and analyzed using the instrument software (DTS from Malvern Instruments). Reported data are the mean peak positions and standard deviations (mean (SD)).

For stability analysis, liposomes were stored at 4 °C. Before measurements, 20 µL of them were incubated at 20 °C for 0.5 h, diluted, and characterized as described above.