Uniform Chitosan Microspheres for Potential Application to Colon-Specific Drug Delivery
β Scribed by Young Bin Choy; Felice Cheng; Hyungsoo Choi; Kyekyoon (Kevin) Kim
- Publisher
- John Wiley and Sons
- Year
- 2008
- Tongue
- English
- Weight
- 767 KB
- Volume
- 8
- Category
- Article
- ISSN
- 1616-5187
No coin nor oath required. For personal study only.
β¦ Synopsis
Abstract
Uniform chitosan microspheres have been fabricated and weakly crosslinked for potential applications in colonβspecific drug delivery. The effects of microsphere size, crosslinking density and electrostatic interactions between the drug and chitosan on drug release were studied, employing model drugs of different acidities. When the drug was basic, all chitosan spheres exhibited 100% release within 30 min. As the acidity of the drug increased, the release slowed down and depended on the crosslinking density and microsphere size. The release of weakly acidic drug was most suppressed for large spheres (35β38 Β΅m), while the small spheres (23β25 Β΅m) with higher crosslinking exhibited the most retention of highly acidic drug, indicating that they are a promising candidate for colonβspecific delivery.
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