title: Controlled release of biomolecules from pH-sensitive network polymers prepared by radiation polymerization.
abstract: Copolymers of 2-hydroxyethyl methacrylate (HEMA) and methacrylic acid (MAA) based hydrogels containing 5 and 10% of a cross-linking agent were studied as drug delivery systems. Terephthalic acid was covalently linked with HEMA, abbreviated as CA. Radiation copolymerization of HEMA and MAA, mixed with a particulate glibenclamide with the various ratios CA as crosslinking agent were carried out at the room temperature. The structure of the CA was confirmed by FTIR, H NMR and C NMR spectroscopy. The compositions of the cross-linked three-dimensional polymers were determined by FTIR spectroscopy. Glass transition temperature (T) of the network polymers was determined calorimetrically. The hydrolysis of drug-polymer conjugates was carried out in cellophane membrane dialysis bags containing an aqueous buffer solution (pH 7.4 and pH 1) at 37 degree C. The drug-release profiles indicate that amount drug release depends on their degree of swelling and cross-linking.
authors.affiliation: Faculty of Science, Chemistry Department, Azarbaijan University of Tarbiat Moallem, Tabriz, Iran. mmahkam@yahoo.com
authors.forename: Mehrdad
authors.initials: M
authors.lastname: Mahkam
authors.forename: Mojgan
authors.initials: M
authors.lastname: Allahverdipoor
mesh_terms: D002152:Calorimetry, Differential Scanning; D002851:Chromatography, High Pressure Liquid; D003432:Cross-Linking Reagents / Q000737:chemistry; D003692:Delayed-Action Preparations; D004339:Drug Compounding; D016503:Drug Delivery Systems; D005905:Glyburide / Q000008:administration & dosage / Q000737:chemistry; D006358:Hot Temperature; D020100:Hydrogels; D006863:Hydrogen-Ion Concentration; D006868:Hydrolysis; D007052:Ibuprofen / Q000008:administration & dosage / Q000737:chemistry; D008689:Methacrylates / Q000138:chemical synthesis / Q000737:chemistry*; D044367:Phase Transition; D010795:Phthalic Acids / Q000737:chemistry; D011102:Polyhydroxyethyl Methacrylate / Q000138:chemical synthesis / Q000737:chemistry*; D011355:Prodrugs / Q000138:chemical synthesis / Q000737:chemistry; D017550:Spectroscopy, Fourier Transform Infrared; D013997:Time Factors; D014965:X-Rays
chemical_list: D003432:Cross-Linking Reagents; D003692:Delayed-Action Preparations; D020100:Hydrogels; D008689:Methacrylates; D010795:Phthalic Acids; D011355:Prodrugs; D011102:Polyhydroxyethyl Methacrylate; C059480:poly(hydroxyethyl methacrylate-methacrylic acid)hydrogel; C011363:terephthalic acid; D005905:Glyburide; D007052:Ibuprofen