McClay Research Centre, School of Pharmacy, Queen's University Belfast, 97 Lisburn Road, Belfast BT9 7BL, Northern Ireland, UK.
Biomaterials. 2009 Dec;30(35):6739-47. doi: 10.1016/j.biomaterials.2009.08.047. Epub 2009 Sep 17.
Microbial adhesion to silicone elastomer biomaterials is a major problem often resulting in infection and medical device failure. Several strategies have been employed to modulate eukaryotic cell adhesion and to hamper bacterial adherence to polymeric biomaterials. Chemical modification of the surface by grafting of polyethylene glycol (PEG) chains or the incorporation of non-antibiotic antimicrobial agents such as triclosan into the biomaterial matrix may reduce bacterial adhesion. Here, such strategies are simultaneously applied to the preparation of both condensation-cure and addition-cure silicone elastomer systems, seeking a sustained release antimicrobial device biomaterial. The influence of triclosan incorporation and degree of pegylation on antimicrobial release, surface microbial adherence and persistence (Escherichia coli and Staphylococcus epidermidis) were evaluated in vitro. Non-pegylated silicone elastomers provided an increased percentage release of triclosan extending over a relatively short duration (99% release by day 64) compared with their pegylated (4% w/w) counterparts (65% and 72% release by day 64, for condensation and addition-cure systems respectively). Viable E. coli adherence to a non-pegylated silicone elastomer containing 1% w/w triclosan was reduced by over 99% after 24 h compared to the non-pegylated silicone elastomer containing no triclosan. No viable S. epidermidis adhered to any of the triclosan-loaded (>0.1% w/w) formulations other than the control. Persistence of the antimicrobial activity of the triclosan-loaded pegylated silicone elastomers continued for at least 70 days compared to the triclosan-loaded non-pegylated elastomers (at least 49 days). Understanding how PEG affects the release of triclosan from silicone elastomers may prove useful in the development of a biomaterial providing prolonged, effective antimicrobial activity.
微生物黏附在硅橡胶弹性体生物材料上是一个主要问题，常常导致感染和医疗设备故障。人们已经采用了几种策略来调节真核细胞黏附，并阻止细菌黏附在聚合生物材料上。通过接枝聚乙二醇 (PEG) 链或在生物材料基质中掺入非抗生素类抗菌剂（如三氯生）来对表面进行化学修饰，可能会减少细菌黏附。在这里，这些策略同时应用于缩合固化和加成固化硅橡胶弹性体系统的制备，寻求一种具有持续释放抗菌性能的装置生物材料。评估了三氯生掺入和 PEG 化程度对抑菌释放、表面微生物黏附及持久性（大肠杆菌和表皮葡萄球菌）的影响，所有实验均在体外进行。与未 PEG 化的硅橡胶弹性体相比，未 PEG 化的硅橡胶弹性体提供了一个相对较短时间内（第 64 天释放 99%）的三氯生的释放百分比增加，而其 PEG 化（缩合固化和加成固化系统分别为第 64 天释放 65%和 72%）。与不含三氯生的未 PEG 化硅橡胶弹性体相比，含有 1%w/w 三氯生的未 PEG 化硅橡胶弹性体在 24 小时后对大肠杆菌的黏附减少了 99%以上。除对照外，任何负载三氯生（>0.1%w/w）配方都没有可存活的表皮葡萄球菌黏附。与负载未 PEG 化三氯生的硅橡胶弹性体（至少 49 天）相比，负载 PEG 化三氯生的硅橡胶弹性体的抗菌活性持续至少 70 天。了解 PEG 如何影响三氯生从硅橡胶弹性体中的释放，可能有助于开发提供长期、有效抗菌活性的生物材料。
