Preparation of Drug-Loaded Composites by Supercritical Carbon Dioxide Impregnation

The use of biocompatible polymeric devices loaded with drugs or bioactive compounds is growing, and it is seen as an excellent alternative to conventional implants or to other clinical therapies. In recent years, the supercritical carbon dioxide process has been developed and received increased attention. In this study, drug-loaded polymer microparticles were prepared using a supercritical solution impregnation process with cefadroxil as the model drug and a nano-hydroxyapatite/chitosan/poly(lactic acid) composite as the drug carrier. The morphology and functional groups of the drug-loaded microparticles were characterized using scanning electron microscopy and Fourier transform infrared analysis. The effects of pressure and temperature on the drug loading and release properties of the prepared microparticles were investigated. The in vitro drug release kinetics of drug-loaded microparticles were studied using five models. These results indicated that the supercritical solution impregnation process did not influence the morphology of the drug-loaded polymer microparticles. The drug was released after more than 50 h and the drug release kinetics showed that the drug release of the drug loaded composite was basically consistent with the Weibull model. This composite is expected to be used as an implant material in the medical field.