Preparation and hydrolytic erosion of differently structured PLGA nanoparticles with chitosan modification.

Two types of poly-lactic-co-glycolic acid (PLGA) based nanoparticles were prepared by surface modification (C-NPs) and homogeneous modification (G-NPs) with chitosan. The naked PLGA NPs were served as control. These nanoparticles all showed regularly spherical shape with mean diameters as 191.3 ± 3.6 nm, 211.9 ± 13.2 nm and 187.5 ± 17.6 nm for PLGA NPs, C-NPs and G-NPs, respectively. Their zeta potentials were -22.4 ± 1.31 mV, -8.7 ± 0.45 mV, -3.1 ± 0.12 mV, respectively. Both C-NPs (15.3% PLGA remained after 2 weeks) and G-NPs (3.7% PLGA remained after 2 weeks) had higher hydrolysis rate than PLGA NPs (18.4% PLGA remained after 6 weeks), with G-NPs showing the highest rate in hydrolysis due to the incorporation of chitosan and its self-assembled structure. Self-assembling properties and controllable biodegradability of G-NPs indicated that it could be a promising drug delivery carrier for tumor drug delivery.