title: Preparation and characterization of glycidyl methacrylate organo bridges grafted mesoporous silica SBA-15 as ibuprofen and mesalamine carrier for controlled release.
abstract: Mesoporous silica SBA-15 was synthesized and functionalized with bridged polysilsesquioxane monomers obtained by the reaction of 3-aminopropyltriethoxy silane with glycidyl methacrylate in 2:1 ratio. The synthesized mesoporous silica materials were characterized by elemental analysis, infrared spectroscopy, nuclear magnetic resonance spectroscopy, nitrogen adsorption, X-ray diffraction, thermogravimetry and scanning electron microscopy. The nuclear magnetic resonance in the solid state is in agreement with the sequence of carbon distributed in the attached organic chains, as expected for organically functionalized mesoporous silica. After functionalization with organic bridges the BET surface area was reduced from 1311.80 to 494.2m(2)g(-1) and pore volume was reduced from 1.98 to 0.89cm(3)g(-1), when compared to original precursor silica. Modification of the silica surface with organic bridges resulted in high loading capacity and controlled release of ibuprofen and mesalamine in biological fluids. The Korsmeyer-Peppas model better fits the release data indicating Fickian diffusion and zero order kinetics for synthesized mesoporous silica. The drug release rate from the modified silica was slow in simulated gastric fluid, (pH1.2) where less than 10% of mesalamine and ibuprofen were released in initial 8h, while comparatively high release rates were observed in simulated intestinal (pH6.8) and simulated body fluids (pH7.2). The preferential release of mesalamine at intestinal pH suggests that the modified silica could be a simple, efficient, inexpensive and convenient carrier for colon targeted drugs, such a mesalamine and also as a controlled drug release system.
authors.affiliation: Institute of Chemistry, University of Campinas, UNICAMP, P.O. Box 6154, 13084-971 Campinas, SP, Brazil; Interdisciplinary Research Centre in Biomedical Materials (IRCBM), COMSATS Institute of Information Technology, Lahore, Pakistan. Electronic address: fozia@iqm.unicamp.br.
authors.forename: Fozia
authors.initials: F
authors.lastname: Rehman
authors.affiliation: Interdisciplinary Research Centre in Biomedical Materials (IRCBM), COMSATS Institute of Information Technology, Lahore, Pakistan.
authors.forename: Abdur
authors.initials: A
authors.lastname: Rahim
authors.affiliation: Institute of Chemistry, University of Campinas, UNICAMP, P.O. Box 6154, 13084-971 Campinas, SP, Brazil.
authors.forename: Claudio
authors.initials: C
authors.lastname: Airoldi
authors.affiliation: Institute of Chemistry, University of Campinas, UNICAMP, P.O. Box 6154, 13084-971 Campinas, SP, Brazil.
authors.forename: Pedro L O
authors.initials: PLO
authors.lastname: Volpe
mesh_terms: D003692:Delayed-Action Preparations / Q000737:chemistry*; D004852:Epoxy Compounds / Q000737:chemistry*; D007052:Ibuprofen / Q000737:chemistry / Q000493:pharmacokinetics*; D019804:Mesalamine / Q000737:chemistry / Q000493:pharmacokinetics*; D008689:Methacrylates / Q000737:chemistry*; D008954:Models, Biological; D012822:Silicon Dioxide / Q000737:chemistry*
chemical_list: D003692:Delayed-Action Preparations; D004852:Epoxy Compounds; D008689:Methacrylates; C509969:SBA-15; D019804:Mesalamine; D012822:Silicon Dioxide; C007870:glycidyl methacrylate; D007052:Ibuprofen
keywords: Drug delivery; Glycidyl methacrylate; Ibuprofen; Mesalamine; Mesoporous silica