title: Synthesis of chitosan-PEO hydrogels via mesylation and regioselective Cu(I)-catalyzed cycloaddition.
abstract: In this work, a well-defined hydrogel was developed by coupling chitosan with PEO through "click chemistry". Azide functionalities were introduced onto chitosan, through mesylation of C-6 hydroxyl groups, and reacted with a di-alkyne PEO by a regioselective Cu(I)-catalyzed cycloaddition. This synthetic approach allowed us to obtain a hydrogel with a controlled crosslinking degree. In fact, the extent of coupling is strictly dependent on the amount of azido groups on chitosan, which in turn can be easily modulated. The obtained hydrogel, with a crosslinking degree of around 90%, showed interesting swelling properties. With respect to chitosan hydrogels reported in literature, a considerably higher equilibrium uptake was reached (940%). The possibility to control the crosslinking degree of hydrogel and its capability to rapidly absorb high amounts of water make this material suitable for several applications, such as controlled drug release and wound healing.
authors.affiliation: Institute for Polymers, Composites and Biomaterials, CNR, Via Campi Flegrei 34, 80078 Pozzuoli (Naples), Italy. Electronic address: pasquale.tirino@unina.it.
authors.forename: Pasquale
authors.initials: P
authors.lastname: Tirino
authors.affiliation: Department of Chemistry "Paolo Corradini", University of Naples "Federico II", Via Cinthia, Naples, Italy. Electronic address: sariala4@alice.it.
authors.forename: Rosaria
authors.initials: R
authors.lastname: Laurino
authors.affiliation: Department of Chemistry "Paolo Corradini", University of Naples "Federico II", Via Cinthia, Naples, Italy. Electronic address: giovanni.maglio@unina.it.
authors.forename: Giovanni
authors.initials: G
authors.lastname: Maglio
authors.affiliation: Institute for Polymers, Composites and Biomaterials, CNR, Via Campi Flegrei 34, 80078 Pozzuoli (Naples), Italy. Electronic address: mario.malinconico@ictp.cnr.it.
authors.forename: Mario
authors.initials: M
authors.lastname: Malinconico
authors.affiliation: Institute for Polymers, Composites and Biomaterials, CNR, Via Campi Flegrei 34, 80078 Pozzuoli (Naples), Italy. Electronic address: giovanna.gomez@ictp.cnr.it.
authors.forename: Giovanna Gomez
authors.initials: GG
authors.lastname: d'Ayala
authors.affiliation: Institute for Polymers, Composites and Biomaterials, CNR, Via Campi Flegrei 34, 80078 Pozzuoli (Naples), Italy. Electronic address: paola.laurienzo@ictp.cnr.it.
authors.forename: Paola
authors.initials: P
authors.lastname: Laurienzo
mesh_terms: D048271:Chitosan / Q000138:chemical synthesis / Q000737:chemistry*; D057930:Click Chemistry / Q000379:methods; D061565:Cycloaddition Reaction; D020100:Hydrogels / Q000737:chemistry*; D011092:Polyethylene Glycols / Q000737:chemistry*
chemical_list: D020100:Hydrogels; D011092:Polyethylene Glycols; D048271:Chitosan
keywords: (4-Chlorophenyl)methanesulfonyl chloride (PubChem CID: 227304); Bromocopper; Chitosan; Click chemistry; Hydrate (PubChem CID: 24654); Hydrazine; N-ethyl-N-propan-2-ylpropan-2-amine (PubChem CID: 81531); Propyl-2-ynyl carbonochloridate (PubChem CID: 3356829); Sodium; Triphenylphosphane (PubChem CID: 11251615).; Well-defined hydrogels; azide (PubChem CID: 33557)