Future Industries Institute , The University of South Australia , Mawson Lakes , SA 5095 , Australia.
School of Information Technology and Mathematical Sciences , University of South Australia , Mawson Lakes Campus , Mawson Lakes , SA 5095 , Australia.
ACS Appl Mater Interfaces. 2019 Feb 20;11(7):7320-7329. doi: 10.1021/acsami.8b16853. Epub 2019 Feb 8.
The growing number of patient morbidity related to nosocomial infections has placed an importance on the development of new antibacterial coatings for medical devices. Here, we utilize the versatile adhesion property of polydopamine (pDA) to design an antibacterial coating that possesses low-fouling and nitric oxide (NO)-releasing capabilities. To demonstrate this, glass substrates were functionalized with pDA via immersion in alkaline aqueous solution containing dopamine, followed by grafting of low-fouling polymer (poly(ethylene glycol) (PEG)) via Michael addition and subsequent formation of N-diazeniumdiolate functionalities (NO precursors) by purging with NO gas. X-ray photoelectron spectroscopy confirmed the successful grafting of PEG and formation of N-diazeniumdiolate on polydopamine-coated substrates. NO release from the coating was observed over 2 days, and NO loading is tunable by the pDA film thickness. The antibacterial efficiency of the coatings was assessed using Gram-negative Pseudomonas aeruginosa (i.e., wild-type PAO1 and multidrug-resistant PA37) and Gram-positive Staphylococcus aureus (ATCC 29213). The NO-releasing PEGylated pDA film inhibited biofilm attachment by 96 and 70% after exposure to bacterial culture solution for 24 and 36 h, respectively. In contrast, films that do not contain NO failed to prevent biofilm formation on the surfaces at these time points. Furthermore, this coating also showed 99.9, 97, and 99% killing efficiencies against surface-attached PAO1, PA37, and S. aureus bacteria. Overall, the combination of low-fouling PEG and antibacterial activity of NO in pDA films makes this coating a potential therapeutic option to inhibit biofilm formation on medical devices.
越来越多的医院感染相关的患者发病率使开发新的抗菌涂层成为医疗器械的重要任务。在这里,我们利用聚多巴胺(pDA)的多功能粘附特性来设计一种具有低污染和一氧化氮(NO)释放能力的抗菌涂层。为此,通过将多巴胺溶于碱性水溶液中使玻璃基底功能化,然后通过迈克尔加成接枝低污染聚合物(聚乙二醇(PEG)),并通过用 NO 气体吹扫形成 N-二氮烯二酸盐官能团(NO 前体)来实现。X 射线光电子能谱证实了 PEG 的成功接枝和 pDA 涂层基底上 N-二氮烯二酸盐的形成。观察到涂层在 2 天内释放 NO,并且可以通过 pDA 膜厚度来调节 NO 负载量。使用革兰氏阴性铜绿假单胞菌(即野生型 PAO1 和多药耐药性 PA37)和革兰氏阳性金黄色葡萄球菌(ATCC 29213)评估了涂层的抗菌效率。NO 释放的 PEG 化 pDA 薄膜在暴露于细菌培养液 24 和 36 小时后分别抑制生物膜附着 96%和 70%。相比之下,不包含 NO 的薄膜在这些时间点未能防止表面生物膜的形成。此外,该涂层对附着在表面上的 PAO1、PA37 和金黄色葡萄球菌的杀灭效率分别达到 99.9%、97%和 99%。总的来说,低污染 PEG 和 pDA 薄膜中 NO 的抗菌活性的结合使这种涂层成为抑制医疗器械上生物膜形成的潜在治疗选择。