Preparation and properties of spherical chitosan hydrogel crosslinked with L-cystine for Cu~(2+) adsorption

Spherical chitosan hydrogel crosslinked with L-cystine(L-CYS)was synthesized by the dropping method.Chemical structure characterization of the product was performed with FTIR,13C NMR and SEM.The results showed that chitosan was amidated and esterified with L-cystine,resulting in internal porous structure.The disulfide bond on L-CYS contributed to Cu2+ adsorption.The adsorption capacity for Cu2+ reached 72.96 mg·g-1,which was close to that of the uncrosslinked chitosan hydrogel.But the anti-swelling property was better than the latter.