title: Multiresponsive hydrogels based on xylan-type hemicelluloses and photoisomerized azobenzene copolymer as drug delivery carrier.
abstract: Stimulus-responsive hydrogels, which can undergo significant physicochemical changes in response to various physical or chemical stimuli, have drawn wide attention in many fields. In this study, novel photoresponsive hydrogels prepared by free radical copolymerization of xylan-type hemicellulose methacrylate with 4-[(4-acryloyloxyphenyl)azo]benzoic acid (AOPAB) were investigated, which showed multiresponsive behaviors to pH, water/ethanol alternating solutions, and light. The swelling ratios of the prepared hydrogels in distilled water decreased from 9.8 to 2.2 g/g with AOPAB content increase from 2% to 16%. The hydrogel displayed rapid swelling and deswelling performance in water and ethanol alternating solutions. Additionally, under UV irradiation the trans-conformation of azobenzene in the hydrogel would generally convert into the cis-conformation and resulted in the hydrophilic/hydrophobic balance variation of the hydrogel. Therefore, the hydrogel loaded with vitamin B12 (VB12) showed a higher drug cumulative release rate under UV irradiation than that without UV irradiation.
authors.affiliation: State Key Laboratory of Pulp and Paper Engineering, South China University of Technology , Guangzhou, 510640, China.
authors.forename: Xuefei
authors.initials: X
authors.lastname: Cao
authors.forename: Xinwen
authors.initials: X
authors.lastname: Peng
authors.forename: Linxin
authors.initials: L
authors.lastname: Zhong
authors.forename: Runcang
authors.initials: R
authors.lastname: Sun
mesh_terms: D001391:Azo Compounds / Q000737:chemistry*; D004337:Drug Carriers / Q000737:chemistry*; D016503:Drug Delivery Systems / Q000295:instrumentation*; D020100:Hydrogels / Q000737:chemistry*; D006863:Hydrogen-Ion Concentration; D057927:Hydrophobic and Hydrophilic Interactions; D058105:Polymerization / Q000528:radiation effects; D011108:Polymers / Q000138:chemical synthesis / Q000737:chemistry*; D011134:Polysaccharides / Q000737:chemistry*; D014466:Ultraviolet Rays; D014990:Xylans / Q000737:chemistry*
chemical_list: D001391:Azo Compounds; D004337:Drug Carriers; D020100:Hydrogels; D011108:Polymers; D011134:Polysaccharides; D014990:Xylans; C007916:hemicellulose; C009850:azobenzene
keywords: azobenzene; drug delivery; hydrogel; multiresponse; xylan-type hemicelluloses