Materials Chemistry Research Centre, Department of Chemistry, University College London, 20 Gordon Street, London WC1H 0AJ, United Kingdom.
Department of Chemical Engineering, University College London, Torrington Place, London WC1E 7JE, United Kingdom.
ACS Appl Mater Interfaces. 2020 Oct 28;12(43):49021-49029. doi: 10.1021/acsami.0c07691. Epub 2020 Oct 19.
Thiolate-gold nanoclusters have various applications. However, most of the synthesis methods require prolonged synthesis times from several hours to days. In the present study, we report a rapid synthesis method for [Au(Cys)] nanoclusters and their application for photobactericidal enhancement. For [Au(Cys)] synthesis, we employed a tube-in-tube membrane reactor using CO as a reducing agent at elevated temperatures. This approach allows continuous generation of high-quality [Au(Cys)] within 3 min. Photobactericidal tests against showed that crystal violet-treated polymer did not have photobactericidal activity, but addition of [Au(Cys)] in the treated polymer demonstrated a potent photobactericidal activity at a low white light flux, resulting in >4.29 log reduction in viable bacteria numbers. Steady-state and time-resolved photoluminescence spectroscopies demonstrated that after light irradiation, photoexcited electrons in crystal violet flowed to [Au(Cys)] in the silicone, suggesting that redox reaction from [Au(Cys)] enhanced the photobactericidal activity. Stability tests revealed that leaching of crystal violet and [Au(Cys)] from the treated silicone was negligible and cyclic testing showed that the silicone maintained a strong photobactericidal activity after repeated use.
硫醇金纳米簇具有多种应用。然而，大多数合成方法需要数小时到数天的长时间合成。在本研究中，我们报告了一种快速合成[Au(Cys)]纳米簇的方法及其在光杀菌增强中的应用。对于[Au(Cys)]的合成，我们采用了一种管式膜反应器，在高温下使用 CO 作为还原剂。这种方法允许在 3 分钟内连续生成高质量的[Au(Cys)]。对 进行的光杀菌测试表明，经结晶紫处理的聚合物没有光杀菌活性，但在处理后的聚合物中添加[Au(Cys)]在低白光通量下表现出很强的光杀菌活性，导致活菌数减少超过 4.29 log。稳态和时间分辨光致发光光谱表明，在光照射后，结晶紫中的光激发电子流向硅酮中的[Au(Cys)]，表明[Au(Cys)]的氧化还原反应增强了光杀菌活性。稳定性测试表明，处理后的硅酮中结晶紫和[Au(Cys)]的浸出可以忽略不计，循环测试表明，硅酮在反复使用后仍保持很强的光杀菌活性。
