Preparation and Drug Release of Aspirin-Loaded PLGA-PEG-PLGA/Montmorillonite Microparticles

A polymerization method was used to synthesize biodegradable poly(lactide-co-glycolide)/poly(ethyleneglycol)/poly(lactide-co-glycolide) (PLGA-PEG-PLGA) copolymers. These copolymers were then used to prepare microparticles for encapsulating drug (aspirin). The results of X-ray diffraction (XRD) analysis showed that the montmorillonite (MMT) can be converted into organic montmorillonite (o-MMT). Subsequently, the emulsion solvent evaporation method was used to separately prepare aspirin-loaded PLGA-PEG-PLGA and aspirin-loaded PLGA-PEG-PLGA/o-MMT microparticles. The results of scanning electron microscopy (SEM) showed that microparticle formation was related to the polyvinyl alcohol (PVA) concentration and the proportion of o-MMT. In addition, the ultraviolet-visible (UV-Vis) spectroscopy was conducted to determine the release rate of these microparticles.