title: Drug release from the enzyme-degradable and pH-sensitive hydrogel composed of glycidyl methacrylate dextran and poly(acrylic acid).
abstract: Hydrogels composed of glycidyl methacrylate dextran (GMD) and poly(acrylic acid, PAA) were prepared by UV irradiation method for colon-specific drug delivery. GMD was synthesized by coupling of glycidyl methacrylate to dextran in the presence of 4-(N,N-dimethylamino)pyridine. GMD was photo-polymerized by ammonium peroxydisulfate as initiating system in phosphate-buffered solution (0.1 M, pH 7.4). And then, acrylic acid monomer was added and subsequently heat-polymerized by 2,2'-azobisisobutyronitrile as an initiator. The hydrogels exhibited high swelling ratio (about 20) at 37 degrees C, and showed a pH-dependent swelling behavior. In addition, the swelling ratio of the hydrogel was remarkably enhanced to about 45 times in the presence of dextranase at pH 7.4. The swelling-deswelling behavior proceeded reversibly for the GMD/PAA hydrogels between pH 2 and pH 7.4. Release of 5-aminosalicylic acid from the GMD/PAA hydrogels was evaluated in simulated gastrointestinal pH fluids in the absence or presence of dextranase. We concluded that the hydrogels prepared could be used as a dual-sensitive drug carrier for sequential release in gastrointestinal tract.
authors.affiliation: College of Pharmacy and Research Institute of Drug Development, Chonnam National University, Gwangju 500757, Korea.
authors.forename: In-Sook
authors.initials: IS
authors.lastname: Kim
authors.forename: In-Joon
authors.initials: IJ
authors.lastname: Oh
mesh_terms: D000180:Acrylic Resins / Q000737:chemistry; D000894:Anti-Inflammatory Agents, Non-Steroidal / Q000737:chemistry / Q000378:metabolism; D003910:Dextranase / Q000378:metabolism; D003911:Dextrans / Q000737:chemistry; D004337:Drug Carriers / Q000138:chemical synthesis / Q000737:chemistry*; D004852:Epoxy Compounds / Q000737:chemistry; D020100:Hydrogels / Q000138:chemical synthesis / Q000737:chemistry* / Q000378:metabolism; D006863:Hydrogen-Ion Concentration; D019804:Mesalamine / Q000737:chemistry / Q000378:metabolism; D008689:Methacrylates / Q000737:chemistry; D012995:Solubility; D013997:Time Factors
chemical_list: D000180:Acrylic Resins; D000894:Anti-Inflammatory Agents, Non-Steroidal; D003911:Dextrans; D004337:Drug Carriers; D004852:Epoxy Compounds; D020100:Hydrogels; D008689:Methacrylates; D019804:Mesalamine; C006903:carbopol 940; D003910:Dextranase; C007870:glycidyl methacrylate