LOADING LEVEL INFLUENCE ON DRUG RELEASE FROM ETHYLENE-GLYCOL DIMETHACRYLATE CROSS-LINKED POLY(2-HYDROXYETHYL METHACRYLATE) MICROSPHERES

This report analyses the loading process of EGDMA crosslinked PHEMA microspheres by soaking with Ketoprofen in presence of different solvents: methanol, ethanol, isopropanol and water and the influence of the loading levels on release. The effect of the soaking temperature was also studied. Methanol and ethanol prove to be the most suitable loading solvents at soaking temperatures of at least 40-degrees-C. The release depends on the dissolution of Ketoprofen in the swollen gel and follows a kinetics approaching zero order particularly at the higher loading levels. The release rate rises with the increase in the loading levels of the drug in the microspheres.