title: Uniform chitosan microspheres for potential application to colon-specific drug delivery.
abstract: Uniform chitosan microspheres have been fabricated and weakly crosslinked for potential applications in colon-specific 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 (35-38 microm), while the small spheres (23-25 microm) with higher crosslinking exhibited the most retention of highly acidic drug, indicating that they are a promising candidate for colon-specific delivery.
authors.affiliation: Department of Electrical and Computer Engineering, Thin Film and Charged Particle Research Laboratory, University of Illinois at Urbana-Champaign, Urbana, IL 61801, USA.
authors.forename: Young Bin
authors.initials: YB
authors.lastname: Choy
authors.forename: Felice
authors.initials: F
authors.lastname: Cheng
authors.forename: Hyungsoo
authors.initials: H
authors.lastname: Choi
authors.forename: Kyekyoon Kevin
authors.initials: KK
authors.lastname: Kim
mesh_terms: D048271:Chitosan / Q000008:administration & dosage* / Q000737:chemistry; D003106:Colon / Q000378:metabolism*; D016503:Drug Delivery Systems; D008855:Microscopy, Electron, Scanning; D008863:Microspheres; D008970:Molecular Weight
chemical_list: D048271:Chitosan