title: Drug release from xyloglucan beads coated with Eudragit for oral drug delivery.
abstract: Xyloglucan (XG), which exhibits thermal sol to gel transition, non-toxicity, and low gelation concentration, is of interest in the development of sustained release carriers for drug delivery. Drug-loaded XG beads were prepared by extruding dropwise a dispersion of indomethacin in aqueous XG solution (2 wt.-%) through a syringe into corn oil. Enteric coating of XG bead was performed using Eudragit L 100 to improve the stability of XG bead in gastrointestinal (GI) track and to achieve gastroresistant drug release. Release behavior of indomethacin from XG beads in vitro was investigated as a function of loading content of drug, pH of release medium, and concentration of coating agent. Adhesive force of XG was also measured using the tensile test. Uniform-sized spherical beads with particle diameters ranging from 692 +/- 30 to 819 +/- 50 microm were obtained. The effect of drug content on the release of indomethacin from XG beads depended on the medium pH. Release of indomethacin from XG beads was retarded by coating with Eudragit and increased rapidly with the change in medium pH from 1.2 to 7.4. Adhesive force of XG was stronger than that of Carbopol 943 P, a well-known commercial mucoadhesive polymer, in wet state. Results indicate the enteric-coated XG beads may be suitable as a carrier for oral drug delivery of irritant drug in the stomach.
authors.affiliation: School of Agricultural Biotechnology, Seoul National University, Seoul 151-742, Korea.
authors.forename: Mi Kyong
authors.initials: MK
authors.lastname: Yoo
authors.forename: Hoo Kyun
authors.initials: HK
authors.lastname: Choi
authors.forename: Tae Hee
authors.initials: TH
authors.lastname: Kim
authors.forename: Yun Jaie
authors.initials: YJ
authors.lastname: Choi
authors.forename: Toshihiro
authors.initials: T
authors.lastname: Akaike
authors.forename: Mayumi
authors.initials: M
authors.lastname: Shirakawa
authors.forename: Chong Su
authors.initials: CS
authors.lastname: Cho
mesh_terms: D000284:Administration, Oral; D000894:Anti-Inflammatory Agents, Non-Steroidal / Q000008:administration & dosage; D003692:Delayed-Action Preparations; D004337:Drug Carriers; D005782:Gels; D005936:Glucans / Q000737:chemistry*; D006863:Hydrogen-Ion Concentration; D007213:Indomethacin / Q000008:administration & dosage; D008855:Microscopy, Electron, Scanning; D008863:Microspheres; D010316:Particle Size; D011109:Polymethacrylic Acids / Q000737:chemistry*; D013997:Time Factors; D014990:Xylans / Q000737:chemistry*
chemical_list: D000894:Anti-Inflammatory Agents, Non-Steroidal; D003692:Delayed-Action Preparations; D004337:Drug Carriers; D005782:Gels; D005936:Glucans; D011109:Polymethacrylic Acids; D014990:Xylans; C038300:methylmethacrylate-methacrylic acid copolymer; C029353:xyloglucan; D007213:Indomethacin