Synthesis and characterization of novel drug delivery nanoparticles based on miktoarm star terpolymers

Well-defined miktoarm star terpolymers consisting of poly(ethyleneglycol) (PEG), poly(tert-butylacrylate) (PtBA) and polycaprolactone (PCL) were successfully synthesized by combination of click chemistry and single electron transfer-living radical polymerization (SET-LRP) in one-step. PH-sensitive ABC miktoarm star terpolymers, mPEG-b-PAA-b-PCL, were prepared by selective acidolysis of tBA groups of mPEG-b- PtBA-b-PCL. The terpolymers were characterized by FT-IR, 1 H NMR and GPC. The pH sensitivity and selfassembly behavior of nanoparticles were investigated by DLS and TEM techniques. DLS analysis showed that the produced nanoparticles had nanometric size (<200 nm) and low poly dispersity in size at different pHs. Nanoprecipitation method was used to prepare naproxen-loaded nanoparticles. The behavior of Naproxen release from the nanoparticles indicated that the rate of drug release could be effectively controlled by altering the pH values of the environment.