61A-26 |
Preparation and release characteristics of polymer-coated and blended alginate microspheres |
D. W. LEE and H. J. Park. Graduate School of Biotechnology, Korea University, 1, 5-ka, Anam-dong, Sungbuk-ku, Seoul, 136-701, South Korea To prevent a rapid drug release from alginate microspheres in simulated instestinal media, alginate microspheres were coated or blended with polymers. There have been few published articles on polymer-blended microspheres produced from a mixture containing HPMC or Eudragit RS 30D and sodium alginate, contrary to many studies on chitosan-coated microspheres. Because the drug release from polymer-coated and blended microspheres was not systemically investigated, varying the type and amount of polymer added in sodium alginate in previous study, we selected and evaluated three polymers such as HPMC, Eudragit RS 30D, and chitosan as both coating materials and additive polymers for controlling the drug release. The objective was to prepare polymer-coated and blended alginate microspheres in order to control the drug release in simulated intestinal fluid. We focused on the release characteristics of polymer-coated and blended alginate microspheres, varying the type of polymer and its concentration. The alginate microspheres were prepared by dropping the mixture of drug and sodium alginate into CaCl2 solution using spray gun. Polymer-coated microspheres were prepared by adding alginate microspheres into polymer solution with mild stirring. Polymer-blended microspheres were prepared by dropping the mixture of drug, sodium alginate and additive polymer with plasticizer into CaCl2 solution. As the amount of additive polymers in sodium alginate or coating solution increase, the drug release generally decreased. HPMC-blended microspheres swelled but withstood the disintegration, showing an ideal linear release profiles. Chitosan-coated microspheres showed smooth and round surface and extended the release of drug. Other formulations were not significantly effective for controlling the drug release. The drug release from chitosan-coated and HPMC-blended microspheres was controlled. In comparison with chitosan-coated microspheres, HPMC-blended alginate microspheres can be easily made and used for controlled drug delivery systems due to convenient process and controlled drug release.
Session 61A, Carbohydrate
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