2.3 Size and zeta potential of NCs
The size and zeta potential of the NCs were measured by a zetasizer. NCs
with 200 pmol of siRNA were formed at N/P ratio 1, 3, and 5 of RS
peptide and N/P ratio 5, 20, and 30 of RT peptide at room temperature
for 30 minutes. Three N/P ratios of each peptide were selected to
observe different aspects of NCs. Formed NCs were diluted to 200 nM in 1
ml DPBS and filtered with a 0.45-µm syringe filter (GVS, Bologna,
Italy). Each NC was loaded in a cell (Ratiolab, Dreieich, Germany).
Hydrodynamic radius and zeta potential were measured using a zetasizer
(Malvern Panalytical, Ltd., Malvern, UK, n=3).