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A Freeze-Thawing Method to Prepare Chitosan-Poly(vinyl alcohol) Hydrogels Without Crosslinking Agents and Diflunisal Release Studies
Published on: January 14, 2020
Plasma depolymerization of chitosan in the presence of hydrogen peroxide
Fengming Ma1,2, Zhenyu Wang1,2, Haitian Zhao1
1School of Food Science and Engineering, Harbin Institute of Technology, 73 Huanghe Road, Nangang District, Harbin 150090, China.
Abstract:
The depolymerization of chitosan by plasma in the presence of hydrogen peroxide (H(2)O(2)) was investigated. The efficiency of the depolymerization was demonstrated by means of determination of viscosity-average molecular weight and gel permeation chromatography (GPC). The structure of the depolymerized chitosan was characterized by Fourier-transform infrared spectra (FT-IR), ultraviolet spectra (UV) and X-ray diffraction (XRD). The results showed that chitosan can be effectively degradated by plasma in the presence of H(2)O(2). The chemical structure of the depolymerized chitosan was not obviously modified. The combined plasma/H(2)O(2) method is significantly efficient for scale-up manufacturing of low molecular weight chitosan.
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