Charles Institute of Dermatology, School of Medicine and Medical Sciences, University College Dublin , Belfield, Dublin Dublin 4, Ireland.
Microbiology and Centre for Research in Medical Devices (CÚRAM), National University of Ireland , Galway SW4, Ireland.
ACS Appl Mater Interfaces. 2016 Oct 12;8(40):26648-26656. doi: 10.1021/acsami.6b11371. Epub 2016 Sep 29.
A multifunctional branched copolymer was synthesized by Reversible Addition-Fragmentation Chain Transfer polymerization (RAFT) of poly(ethylene glycol) diacrylate (PEGDA M = 575) and poly(ethylene glycol) methyl methacrylate (PEGMEMA M = 500) at a feed molar ratio of 50:50. Proton nuclear magnetic resonance spectroscopy (H 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.
通过聚乙二醇二丙烯酸酯（PEGDA，M = 575）和聚乙二醇甲基丙烯酸甲酯（PEGMEMA，M = 500）的可逆加成-断裂链转移聚合（RAFT），以 50:50 的进料摩尔比合成了一种多功能支化共聚物。质子核磁共振波谱（H NMR）证实了超支化的分子结构和高乙烯基官能度。通过该 PEGDA/PEGMEMA 共聚物体系中来自乙烯基官能团的“点击”硫醇-烯型迈克尔加成反应与巯基改性透明质酸结合，生成了原位可交联水凝胶体系。此外，将抗菌银磺胺嘧啶（SSD）包封到共聚物体系中，以创建先进的抗菌伤口护理敷料。与 SSD 的直接局部应用相比，该水凝胶对金黄色葡萄球菌、铜绿假单胞菌和大肠杆菌等细菌菌株表现出持续的抗菌活性。此外，体外毒理学评估表明，这种水凝胶-含有低浓度封装的 SSD-支持嵌入式人脂肪来源干细胞（hADSCs）的存活，并抑制上述病原体的生长。在这里，我们证明了这种包封有低浓度（1.0%w/v）SSD 的水凝胶可用作具有抑制病原体生长能力且对 hADSCs 无不良影响的干细胞载体系统。
