title: Thermal treating as a tool for sustained release of indomethacin from Eudragit RS and RL matrices.
abstract: Eudragit RS and RL are biocompatible non-swelling polymers that widely used in the preparation of sustained release drug delivery systems. In this study, the effect of thermal treating on the tensile strength of tablets and release of indomethacin from Eudragit RS and RL matrices were investigated. The results showed that thermal treating at 40 degrees C has no effect on the release of the drug, whereas heat-treating at temperatures higher than 50 or 60 degrees C decreases the release rate of indomethacin from Eudragit RS or RL, respectively. It was shown that the duration of the heat treatment was also an important factor in controlling the release rate of indomethacin from Eudragit matrices. The results showed that an increase in the duration of the heat treatment from 2 to 24 h resulted in a reduction in the release rate of the drug. The heating of the matrices over 24 h had no significant effect on the release rate of indomethacin. It was shown that heat treatment of the matrices over the glass transition temperature of the polymer can prolong the drug release but had no significant effect on the tensile strength of tablets.
authors.affiliation: Department of Pharmaceutics, School of Pharmacy, Tabriz University of Medical Sciences, Iran.
authors.forename: S
authors.initials: S
authors.lastname: Azarmi
authors.forename: J
authors.initials: J
authors.lastname: Farid
authors.forename: A
authors.initials: A
authors.lastname: Nokhodchi
authors.forename: S M
authors.initials: SM
authors.lastname: Bahari-Saravi
authors.forename: H
authors.initials: H
authors.lastname: Valizadeh
mesh_terms: D000180:Acrylic Resins / Q000737:chemistry*; D003692:Delayed-Action Preparations; D004337:Drug Carriers; D004339:Drug Compounding; D006361:Heating / Q000379:methods*; D007213:Indomethacin / Q000737:chemistry*; D008855:Microscopy, Electron, Scanning; D011108:Polymers / Q000737:chemistry*; D016062:Porosity; D012995:Solubility; D013607:Tablets; D013718:Tensile Strength; D013997:Time Factors
chemical_list: D000180:Acrylic Resins; D003692:Delayed-Action Preparations; D004337:Drug Carriers; D011108:Polymers; D013607:Tablets; C050528:Eudragit RS; C058665:Eudragit RL; D007213:Indomethacin