Smart Poly (N-Isopropylacrylamide)-block-Poly (L-Lactide) Nanoparticles for Prolonged Release of Naltrexone

The authors synthesized core-shell smart nanoparticles composed of poly (N-isopropylacrylamide)-b-poly (L-lactide) (PNIPAAm-b-PLA) and developed for narcotic antagonists' drug-delivery purpose. Micelle structure was verified by H-1-NMR, FT-IR, and TEM. Effect of drug loading, polymer composition, and temperature on micelles morphology and diameter was investigated. Stimuli-responsive behaviors of these nanoparticles were determined using a three-factor full factorial experiment. Naltrexone was successfully incorporated into the PLA cores. By varying the PLA to PNIPAAm ratio, drug loading content, and release time were changed. Results suggest that smart micelles can be suitable for preparation of sustained release systems.