title: Release characteristics of brilliant blue from calcium-alginate beads coated with quaternized chitosan.
abstract: Calcium-alginate beads coated with quaternized chitosan were prepared in a neutral environment, and morphologies were observed by SEM. Optimum conditions for the encapsulation and retention of a model drug (brilliant blue, BB) in acid were obtained from studies of preparation conditions, including alginate and quaternized chitosan concentration, calcium chloride (CaCl2) concentration in the gelling medium and by comparing one-step and two-step preparation methods. Results showed that very high BB encapsulation efficiency (99%, w/w) and low leakage in acid (8%, w/w) was achieved from dry beads when 2.0% (w/v) alginate was dropped into 1.0% (w/v) CaCl2 containing 0.3% (w/v) quaternized chitosan by a one-step method. The release of BB in 0.9% (w/v) NaCl was modulated by coating calcium-alginate with different weight average molecule weight (Mw) and degree of substitution (DS) of quaternized chitosan. A decreased of Mw accelerated the release of BB and a high DS value significantly decreased the release in 0.9% (w/v) NaCl.
authors.affiliation: Department of Environmental Science, College of Resource and Environmental Science, Wuhan University, PR China.
authors.forename: X-W
authors.initials: XW
authors.lastname: Shi
authors.forename: Y-M
authors.initials: YM
authors.lastname: Du
authors.forename: J
authors.initials: J
authors.lastname: Li
authors.forename: X-L
authors.initials: XL
authors.lastname: Su
authors.forename: J-H
authors.initials: JH
authors.lastname: Yang
mesh_terms: D000284:Administration, Oral; D000464:Alginates; D001557:Benzenesulfonates / Q000737:chemistry* / Q000493:pharmacokinetics; D002118:Calcium; D004396:Coloring Agents / Q000737:chemistry* / Q000493:pharmacokinetics; D053138:Cyclohexenes / Q000737:chemistry; D004339:Drug Compounding / Q000379:methods*; D020723:Glucuronic Acid; D006603:Hexuronic Acids; D008855:Microscopy, Electron, Scanning; D008863:Microspheres; D008970:Molecular Weight
chemical_list: D000464:Alginates; D001557:Benzenesulfonates; D004396:Coloring Agents; D053138:Cyclohexenes; D006603:Hexuronic Acids; C413286:aglycone 4-hydroxy-2,6,6-trimethyl-1-carboxyaldehyde-1-cyclohexene; D020723:Glucuronic Acid; C006796:brilliant blue; D002118:Calcium