title: An electrostatically crosslinked chitosan hydrogel as a  drug carrier.
abstract: Considerable efforts have been devoted to control and maintain the sustained release of proteins. In this experiment, we used bovine serum albumin-fluorescein isothiocyanate (BSA-FITC) as a model protein to explore the potential utility of a chitosan and glycerol phosphate disodium salt (GP) hydrogel as a protein drug depot. The mixing of chitosan and GP solutions (0, 10, 20 and 30 wt%) formed a liquid at room temperature. At 37 &#176;C, however, the chitosan/GP solutions formed hydrogels through an electrostatic crosslinking process. This electrostatic interaction between the chitosan, cationic amine group, and GP, anionic phosphate group, was confirmed by the changes of zeta potentials and particle sizes of this solution. The electrostatic interaction depended both on the  GP ratios in chitosan and the incubation time of chitosan/GP solutions. Furthermore,  BSA-FITC-loaded chitosan/GP hydrogels were examined for their ability as potential depots for the BSA drugs. Hence, when observed, the BSA-FITC-loaded chitosan/GP hydrogels showed an in vitro sustained release profile of BSA up to 14 days. Collectively, our results show that the chitosan/GP hydrogels described here, can serve as depots for BSA drugs.
authors.affiliation: Hankuk Academy of Foreign Studies, Yongin 449-854, Korea. gaon1995@gmail.com
authors.forename: Ga On
authors.initials: GO
authors.lastname: Kim
authors.forename: Nawoo
authors.initials: N
authors.lastname: Kim
authors.forename: Da Yeon
authors.initials: DY
authors.lastname: Kim
authors.forename: Jin Seon
authors.initials: JS
authors.lastname: Kwon
authors.forename: Byoung-Hyun
authors.initials: BH
authors.lastname: Min
mesh_terms: D048271:Chitosan / Q000737:chemistry* / Q000378:metabolism; D004337:Drug Carriers / Q000737:chemistry*; D016650:Fluorescein-5-isothiocyanate / Q000031:analogs & derivatives* / Q000737:chemistry; D006801:Humans; D020136:Hydrogel, Polyethylene Glycol Dimethacrylate / Q000737:chemistry*; D011506:Proteins / Q000737:chemistry / Q000378:metabolism; D012710:Serum Albumin, Bovine / Q000737:chemistry*; D012996:Solutions; D055672:Static Electricity; D013696:Temperature
chemical_list: D004337:Drug Carriers; D011506:Proteins; D012996:Solutions; C039217:fluorescein isothiocyanate bovine serum albumin; D020136:Hydrogel, Polyethylene Glycol Dimethacrylate; D012710:Serum Albumin, Bovine; D048271:Chitosan; D016650:Fluorescein-5-isothiocyanate