الفهرس 
Acknowledgement
Steeioselective of InteractionOnly 14 pages are availabe for public view
 |  | from | 334 |  |  |
| | | from | 334 | | |
Abstract
Controlled release pharmaceutical dosage forms may offer one or more advantages over conventional or immediate release forms of the same drug, incuding aredced dosing frequency, adecreased incidence and or intensity of adverse effects, agreater selectivity of pharmacologic activity, and amore constant or prolonged therapeutic effect.Ca-alginate beads loaded with ibuprofen or tiaramide were prepared. Alginates with different chemical composition (content of mannuronic acid block to guluronic acid block; MM/ GG ratios) were used. The beads were evaluated as a controlled-release formulation through in-vitro study and in
vivo study.
The most important findings of this work could be summarized in the following:
1-The method of preparation of Ca-alginate beads loaded with ibuprofen or tiaramide was simple, did not require elevated temperature and avoided the use of organic solvent.
2-Some relevant properties of calcium alginate beads including shrinking, swelling, resistance to interference by monovalent cations were highly dependent upon mannuronic acid blocks to gul uronic acid block (MM/ GG) ratio of alginate used. Beads based on alginate rich in guluronic acid block (low MM/GG ratio) showed, low shrinkage, low reswelling and high stability towards non-gelling ions.