title: Synthesis and characterization of a pH-sensitive hydrogel made of pyruvic-acid-modified chitosan.
abstract: Pyruvic-acid-type chitosan (PA-CS) was prepared by the reaction of an amine group on chitosan with a carbonyl group on pyruvic acid. Then, a novel hydrogel film was obtained via cross-linking of poly(ethylene glycol) diglycidyl ether (PEGDE) with PA-CS. 1H-NMR and FT-IR spectrometry were applied for the verification of the CS and PA-CS structure. The degree of swelling was studied by changing the molar ratio of PEGDE and PA-CS. Moreover, the swelling ratio of cross-linked membrane in different pH buffer solutions was measured. The result showed that the swelling of hydrogel exhibited obvious pH-sensitivity. The swelling ratio was higher at pH 1-4 and pH 7-12, but lower at pH 5-6.
authors.affiliation: Department of Chemical Engineering and Technology, Shanghai University, Jiading, Shanghai 201800, China.
authors.forename: Jie
authors.initials: J
authors.lastname: Sun
authors.forename: Jie
authors.initials: J
authors.lastname: Chen
authors.forename: Liming
authors.initials: L
authors.lastname: Yang
authors.forename: Sheng
authors.initials: S
authors.lastname: Wang
authors.forename: Zhijun
authors.initials: Z
authors.lastname: Li
authors.forename: Huifeng
authors.initials: H
authors.lastname: Wu
mesh_terms: D048271:Chitosan / Q000031:analogs & derivatives* / Q000138:chemical synthesis / Q000737:chemistry*; D003432:Cross-Linking Reagents / Q000737:chemistry; D004853:Epoxy Resins / Q000737:chemistry; D020100:Hydrogels / Q000138:chemical synthesis / Q000737:chemistry*; D006863:Hydrogen-Ion Concentration; D009682:Magnetic Resonance Spectroscopy; D019289:Pyruvic Acid / Q000031:analogs & derivatives* / Q000138:chemical synthesis / Q000737:chemistry*; D017550:Spectroscopy, Fourier Transform Infrared
chemical_list: D003432:Cross-Linking Reagents; D004853:Epoxy Resins; D020100:Hydrogels; C035364:Quetol 651; D019289:Pyruvic Acid; D048271:Chitosan