PREPARATION AND CHARACTERIZATION OF PROTEIN-LOADED TEMPERATURE-SENSITIVE PNIPAAm-PLA AND P(NIPAAm-co-DMAAm)-PLA MICROSPHERES

摘要

Temperature-sensitive block copolymers, poly (N-isopropylacrylamide)-b-polylactide (PNIPAAm-PLA) and poly(N-isopropylacrylamide-co-N, N-dimethylacrylamide)-b-polylactide (P(NIPAAm-co-DMAAm)-PLA) were synthesized. BSA-loaded microspheres were fabricated using these block copolymers by a water-in-oil-in-water double emulsion process. The surface and internal morphologies were examined using SEM. The BSA release rate at 37°C increased with the introduction of DMAAm segment that is more hydrophilic than NIPAAm. A higher emulsifier concentration in the internal water phase yielded microspheres with a faster BSA release. In addition, it was found that BSA release from the microspheres responded to the external temperature changes.