title: Stabilization of polymer-hydrogel capsules via thiol-disulfide exchange.
abstract: Polymer hydrogels are used in diverse biomedical applications including drug delivery and tissue engineering. Among different chemical linkages, the natural and reversible thiol-disulfide interconversion is extensively explored to stabilize hydrogels. The creation of macro-, micro-, and nanoscale disulfide-stabilized hydrogels commonly relies on the use of oxidizing agents that may have a detrimental effect on encapsulated cargo. Herein an oxidization-free approach to create disulfide-stabilized polymer hydrogels via a thiol-disulfide exchange reaction is reported. In particular, thiolated poly(methacrylic acid) is used and the conditions of polymer crosslinking in solution and on colloidal porous and solid microparticles are established. In the latter case, removal of the core particles yields stable, hollow, disulfide-crosslinked hydrogel capsules. Further, a procedure is developed to achieve efficient disulfide crosslinking of multilayered polymer films to obtain stable, liposome-loaded polymer-hydrogel capsules that contain functional enzymatic cargo within the liposomal subcompartments. This approach is envisaged to facilitate the development of biomedical applications of hydrogels, specifically those including fragile cargo.
authors.affiliation: Centre for Nanoscience and Nanotechnology, Department of Chemical and Biomolecular Engineering, The University of Melbourne, Parkville, Victoria 3010, Australia.
authors.forename: Siow-Feng
authors.initials: SF
authors.lastname: Chong
authors.forename: Rona
authors.initials: R
authors.lastname: Chandrawati
authors.forename: Brigitte
authors.initials: B
authors.lastname: Städler
authors.forename: Jeongju
authors.initials: J
authors.lastname: Park
authors.forename: Jinhan
authors.initials: J
authors.lastname: Cho
authors.forename: Yajun
authors.initials: Y
authors.lastname: Wang
authors.forename: Zhongfan
authors.initials: Z
authors.lastname: Jia
authors.forename: Volga
authors.initials: V
authors.lastname: Bulmus
authors.forename: Thomas P
authors.initials: TP
authors.lastname: Davis
authors.forename: Alexander N
authors.initials: AN
authors.lastname: Zelikin
authors.forename: Frank
authors.initials: F
authors.lastname: Caruso
mesh_terms: D001672:Biocompatible Materials / Q000737:chemistry*; D002214:Capsules; D004220:Disulfides / Q000737:chemistry*; D020100:Hydrogels / Q000737:chemistry*; D008422:Materials Testing; D010084:Oxidation-Reduction; D011108:Polymers / Q000737:chemistry*; D013438:Sulfhydryl Compounds / Q000737:chemistry*
chemical_list: D001672:Biocompatible Materials; D002214:Capsules; D004220:Disulfides; D020100:Hydrogels; D011108:Polymers; D013438:Sulfhydryl Compounds