**Figure 3. **The effects of N/P ratio on the hydrodynamic diameter and zeta-potential of CS-*g*-(PEI-*b*-mPEG)/siRNA complexes and 25 kDa PEI/siRNA complexes. The diameter of complexes decreased while the N/P ratios increased
from 1 to 10 and then remained constant up to N/P of 20; the zeta-potential of complexes increased in parallel with the rinsing
N/P ratio. **A**: hydrodynamic diameter (mean±SD, n=3); **B**: zeta-potential (mean±SD, n=3).