(475af) pH-Sensitive Drug Delivery System Formulated by Polymerized Bicontinuous Microemulsions for Sustained Enzyme Release

The enzyme beta-galactosidase was encapsulated by photopolymerizing a precursor bicontinuous microemulsion. The microemulsion contained the beta-galactosidase, methyl methacrylate(MMA), acrylic acid(AA), a small amount of ethylene glycol dimethacrylate and the biocompatible surfactant Plurnic F127. The presence of the beta-galactosidase at a concentration level of 5 mg/g did not affect the phase behavior of the microemulsion. Photopolymerization was accomplished using visible light with 2 wt% 2,2-dimethoxy-2-phenyl acetophenone as the photoinitiator. Swelling behavior of the synthesized polymer was pH-dependent. The encapsulation efficiency and activity of the enzyme were also determined in releasing medium with different pH. This system will be a promising candidate for oral administration of enzyme.