Chemical Engineering / Kimya Mühendisliği

Permanent URI for this collectionhttps://hdl.handle.net/11147/14

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Department: search.filters.department.İzmir Institute of Technology. Chemical EngineeringSubject: search.filters.subject.Theophylline

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Now showing 1 - 2 of 2
  • Article
    Citation - WoS: 23
    Citation - Scopus: 27
    In Vitro Drug Release Rates From Asymmetric-Membrane Tablet Coatings: Prediction of Phase-Inversion Dynamics
    (Elsevier Ltd., 2006) Alsoy Altınkaya, Sacide; Yenal, Hacer; Alsoy Altınkaya, Sacide; 03.02. Department of Chemical Engineering; 03. Faculty of Engineering; 01. Izmir Institute of Technology
    Most of the controlled-release systems developed for drug delivery applications depend on membrane technology. The dense structure of some membranes used in controlled-release systems can excessively prolong the release of drug due to the low permeability of the coating to drug. To increase the drug release rate, asymmetric-membrane tablet coatings were prepared by a phase-inversion technique using cellulose acetate/acetone/water solution. The roles of the composition of the membrane solution and the evaporation condition on the release rate of drug were determined using in vitro dissolution and morphological studies and predicted phase diagrams. Results show that drug release from asymmetric-membrane based tablet coatings is primarily governed by the dynamics of the phase-inversion process with zero-order or near-zero-order release easily achievable. In an attempt to derive an empirical expression for the release rate of drug as a function of composition of the coating solution, a statistical experimental design was used. Good fit of the experimental data by the empirical expression was obtained. In addition, the predictive capability of the model equation was also found to be satisfactory. Analysis of the significance of each term in the expression indicates that the cellulose acetate:acetone ratio has the most significant influence on the release rate of theophylline.
  • Article
    Citation - WoS: 106
    Citation - Scopus: 122
    Silk Fibroin as a Novel Coating Material for Controlled Release of Theophylline
    (Elsevier Ltd., 2005) Bayraktar, Oğuz; Malay, Özge; Batıgün, Ayşegül; Batıgün, Ayşegül; Bayraktar, Oğuz; 03.02. Department of Chemical Engineering; 03. Faculty of Engineering; 01. Izmir Institute of Technology
    The aim of this study was to explore potential use of the silk fibroin (SF) as an aqueous coating material for theophylline tablets. We have examined the film forming and coating properties of heat-treated fibroin, SF solution having different amounts of polyethylene glycol (PEG) and 1-ethyl-3-(3-dimethyl aminopropyl)carbodiimide (EDC) cross-linked SF. Heat-treated SF material possessed a brittle structure, which resulted in poor film forming and coating properties. The optimum PEG amount in SF solution was determined as 17% (by weight) for an acceptable film forming and zero order release profile. EDC cross-linked SF has shown a very good film forming and coating property with a potential for sustaining the drug release from coated theophylline tablets. Dissolution data for coated theophylline tablets were analyzed using Ritger and Peppas equation to describe the mechanism of drug release. Drug release from the EDC coated tablets followed zero-order kinetics. Release rate constants were found to be 0.26, 0.19, 0.16% min-1 for single-coated, double coated, and triple coated tablets, respectively. These results clearly demonstrated that silk fibroin has high utility as a novel aqueous coating material for controlled release products.