Effect of ratio of polyoxalate/PLGA microspheres on the release behavior of zaltoprofen

Zaltoprofen, a propionic acid derivative non-steroidal anti-inflammatory drug, was known to have powerful inhibitory effects on acute, subacute and chronic inflammation. For initial release and sustained release, the microspheres were prepared using an emulsion-solvent evaporation method like an O/W emulsion method with varying the ratio of zal-toprofen-loaded polyoxalate (POX)/PLGA micropheres. The morphology of the microspheres was confirmed by scanning electron microscopy. The crystallinity of microspheres was analyzed by X-ray diffraction and differential scanning calorimeter. Fourier transform infrared spectroscopy was used to analyze the chemical structure of microspheres. The increased ratio of POX microspheres affected the initial drug release, and the sustained release of drug was influenced by ratio of PLGA microspheres. In this study, the initial release behavior of zaltoprofen can be controlled by the ratio of POX/PLGA microspheres.