title: Diclofenac sodium releasing pH-sensitive monolithic devices.
abstract: A non-steroidal anti-inflammatory agent, diclofenac sodium (DFNa), was incorporated into the pH-sensitive monolithic systems prepared by crosslinking/copolymerization of 2-hydroxyethyl methacrylate (HEMA) with acrylate-based acidic and basic comonomers, i.e. acrylic acid (AA) and dimethylaminoethyl methacrylate (DMAEMA). Drug loading was done before polymerization and crosslinking. Hence, DFNa-containing polymeric discs approximately 10 mm in diameter and 3.0 mm in thickness were obtained. In vitro release studies were carried out in simulated gastric fluid for 3 h followed by simulated intestinal fluid at 37 degrees C. The release rate of DFNa was controlled by changing the composition of polymeric matrix, disc thickness and the drug loading between 5 and 33 mg/disc. Results indicate that in the low pH of the stomach, swelling degree of the AA-containing gels is low and less than 5% of the drug releases during first 3 h. But, in the intestine, the high pH causes the higher swelling degree of the AA-containing discs, allowing all the drug ( approximately 97.5%) is released. In the presence of DMAEMA in polymeric structure, opposite behavior was observed.
authors.affiliation: Faculty of Pharmacy, Department of Analytical Chemistry, Gazi University, 06330, Ankara, Turkey
authors.forename: Hasan
authors.initials: H
authors.lastname: Basan
authors.forename: Menemşe
authors.initials: M
authors.lastname: Gümüşderelíoğlu
authors.forename: Tevfik
authors.initials: T
authors.lastname: Orbey
mesh_terms: D000179:Acrylates / Q000737:chemistry; D000894:Anti-Inflammatory Agents, Non-Steroidal / Q000737:chemistry*; D004008:Diclofenac / Q000737:chemistry*; D004337:Drug Carriers; D005079:Excipients / Q000737:chemistry; D005744:Gastric Acid; D020100:Hydrogels; D006863:Hydrogen-Ion Concentration; D008689:Methacrylates / Q000737:chemistry; D008855:Microscopy, Electron, Scanning; D011108:Polymers; D013607:Tablets; D013997:Time Factors
chemical_list: D000179:Acrylates; D000894:Anti-Inflammatory Agents, Non-Steroidal; D004337:Drug Carriers; D005079:Excipients; D020100:Hydrogels; D008689:Methacrylates; D011108:Polymers; D013607:Tablets; D004008:Diclofenac; C005044:hydroxyethyl methacrylate; C036658:acrylic acid; C049840:2-(dimethylamino)ethyl methacrylate