title: Preparation and optimization of superabsorbent hydrogel micromatrices based on poly(acrylic acid), partly sodium salt-g-poly(ethylene oxide) for modified release of indomethacin.
abstract: The purpose of this study was to prepare modified-release dosage of indomethacin (IND) in the form of micromatrices based on a superabsorbent hydrogel (SAH), poly(acrylic acid), partly sodium salt-g-poly(ethylene oxide) (PAAc-Na-g-PEO). A soaking procedure was used for the preparation of drug-loaded hydrogel micromatrices. The amount of IND, volume of drug-loading solution, and amount of PAAc-Na-g-PEO granules used for preparing micromatrices were the independent factors. The dependent factors were the measured responses from micromatrices, that is, percent recovery, percent entrapment efficiency, and the time at which 63.2% of the drug was released (T(d), minutes). A three-factor, three-level full factorial design (33) was created to optimize formulations. Nonlinear regression analysis indicated a good correlation between the measured responses and the independent factors. Optimum responses were obtained from medium levels of IND and SAH and low level of drug-loading solution. Differential scanning calorimetry, X-ray diffraction analysis, and scanning electron micrography indicated that IND crystals are physically adsorbed into the pores and irregular spaces of the hydrogel.
authors.affiliation: Department of Pharmaceutical Technology, School of Pharmacy, Ankara University, Tandogan, Ankara, Turkey. nyuksel@pharmacy.ankara.edu.tr
authors.forename: Nilufer
authors.initials: N
authors.lastname: Yuksel
authors.forename: Leyla
authors.initials: L
authors.lastname: Beba
mesh_terms: D000180:Acrylic Resins / Q000737:chemistry*; D000894:Anti-Inflammatory Agents, Non-Steroidal / Q000008:administration & dosage* / Q000737:chemistry; D002152:Calorimetry, Differential Scanning; D003460:Crystallization; D003692:Delayed-Action Preparations; D004337:Drug Carriers / Q000737:chemistry; D020100:Hydrogels; D007213:Indomethacin / Q000008:administration & dosage* / Q000737:chemistry; D008855:Microscopy, Electron, Scanning; D017711:Nonlinear Dynamics; D011092:Polyethylene Glycols / Q000737:chemistry*; D012044:Regression Analysis; D012492:Salts; D014961:X-Ray Diffraction
chemical_list: D000180:Acrylic Resins; D000894:Anti-Inflammatory Agents, Non-Steroidal; D003692:Delayed-Action Preparations; D004337:Drug Carriers; D020100:Hydrogels; D012492:Salts; D011092:Polyethylene Glycols; C006903:carbopol 940; D007213:Indomethacin