title: Poly(ethylene glycol)-Based Hyperbranched Polymer from RAFT and Its Application as a Silver-Sulfadiazine-Loaded Antibacterial Hydrogel in Wound Care.
abstract: A multifunctional branched copolymer was synthesized by Reversible Addition-Fragmentation Chain Transfer polymerization (RAFT) of poly(ethylene glycol) diacrylate (PEGDA Mn= 575) and poly(ethylene glycol) methyl methacrylate (PEGMEMA Mn= 500) at a feed molar ratio of 50:50. Proton nuclear magnetic resonance spectroscopy (1H NMR) confirmed a hyperbranched molecular structure and a high degree of vinyl functionality. An in situ cross-linkable hydrogel system was generated via a "click" thiol-ene-type Michael addition reaction of vinyl functional groups from this PEGDA/PEGMEMA copolymer system in combination with thiol-modified hyaluronic acid. Furthermore, encapsulation of antimicrobial silver sulfadiazine (SSD) into the copolymer system was conducted to create an advanced antimicrobial wound care dressing. This hydrogel demonstrated a sustained antibacterial activity against the bacterial strains Staphylococcus aureus, Pseudomonas aeruginosa, and Escherichia coli in comparison to the direct topical application of SSD. In addition, in vitro toxicology evaluations demonstrated that this hydrogel-with low concentrations of encapsulated SSD-supported the survival of embedded human adipose derived stem cells (hADSCs) and inhibited growth of the aforementioned pathogens. Here we demonstrate that this hydrogel encapsulated with a low concentration (1.0% w/v) of SSD can be utilized as a carrier system for stem cells with the ability to inhibit growth of pathogens and without adverse effects on hADSCs.
authors.affiliation: Charles Institute of Dermatology, School of Medicine and Medical Sciences, University College Dublin , Belfield, Dublin Dublin 4, Ireland.
authors.forename: Sean
authors.initials: S
authors.lastname: McMahon
authors.affiliation: Charles Institute of Dermatology, School of Medicine and Medical Sciences, University College Dublin , Belfield, Dublin Dublin 4, Ireland.
authors.forename: Robert
authors.initials: R
authors.lastname: Kennedy
authors.affiliation: Charles Institute of Dermatology, School of Medicine and Medical Sciences, University College Dublin , Belfield, Dublin Dublin 4, Ireland.
authors.forename: Patrick
authors.initials: P
authors.lastname: Duffy
authors.affiliation: Charles Institute of Dermatology, School of Medicine and Medical Sciences, University College Dublin , Belfield, Dublin Dublin 4, Ireland.
authors.forename: Jeddah Marie
authors.initials: JM
authors.lastname: Vasquez
authors.affiliation: Microbiology and Centre for Research in Medical Devices (CÚRAM), National University of Ireland , Galway SW4, Ireland.
authors.forename: J Gerard
authors.initials: JG
authors.lastname: Wall
authors.affiliation: School of Chemistry, Bangor University , Bangor LL57 2UW, United Kingdom.
authors.forename: Hongyun
authors.initials: H
authors.lastname: Tai
authors.affiliation: Charles Institute of Dermatology, School of Medicine and Medical Sciences, University College Dublin , Belfield, Dublin Dublin 4, Ireland.
authors.forename: Wenxin
authors.initials: W
authors.lastname: Wang
mesh_terms: D000900:Anti-Bacterial Agents; D006801:Humans; D020100:Hydrogels; D011092:Polyethylene Glycols / Q000737:chemistry*; D012834:Silver; D013411:Sulfadiazine
chemical_list: D000900:Anti-Bacterial Agents; D020100:Hydrogels; D013411:Sulfadiazine; D012834:Silver; D011092:Polyethylene Glycols
keywords: antibacterial; hyaluronic acid; hydrogels; hyperbranched polymer; poly(ethylene glycol); thiol−ene click chemistry; wound care