In Situ Study of the Antibacterial Activity and Mechanism of Action of Silver Nanoparticles by Surface-Enhanced Raman Spectroscopy
In Situ Study of the Antibacterial Activity and Mechanism of Action of Silver Nanoparticles by Surface-Enhanced Raman Spectroscopy
复制标题
表面增强拉曼光谱原位研究银纳米粒子的抗菌活性和作用机制
DOI：
10.1021/ac400245j
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发表时间：
2013-06-04
影响因子：
7.4
通讯作者：
Zhang, Kaisong
中科院分区：
文献类型：
--
作者：
Cui, Li;Chen, Pengyu;Zhang, Kaisong
银纳米颗粒（Ag NPs）作为抗菌添加剂广泛应用于商业产品中，并且它们的释放已经引起环境风险。然而，用于Ag NPs毒性检测的常规方法非常耗时，并且作用机制不清楚。我们开发了一种新的，原位，快速，灵敏的指纹方法，使用表面增强拉曼光谱（Sers），研究抗菌活性和机制的银纳米粒子的80和18 nm（Ag 80和Ag 18，分别），通过使用强电磁增强所产生的银纳米粒子。随着银纳米颗粒浓度的增加，观察到代表细菌中各种生物分子的敏感光谱变化。它们不仅允许Sers监测不同尺寸的银纳米颗粒在不同水介质中的抗菌活性，而且还可以在分子水平上研究抗菌机制。Ag18在水中的毒性比Ag80大，但在PBS培养基中的毒性下降到相似的水平。通过与模型化合物的Sers光谱进行比较，在仔细鉴定其化学来源的基础上，提出了抗菌机理。蛋白质、次黄嘌呤、腺苷和鸟苷条带的显著变化表明Ag纳米颗粒对蛋白质和嘌呤代谢过程具有显著影响。最后，通过添加无毒且Sers活性的Au纳米粒子，成功地利用Sers研究了不能产生可观察到的Sers信号的纳米粒子的作用模式。这项工作为今后广泛研究各种非SERS活性纳米颗粒的抗菌机制打开了一扇窗户。
Silver nanoparticles (Ag NPs) are extensively used as an antibacterial additive in commercial products and their release has caused environmental risk. However, conventional methods for the toxicity detection of Ag NPs are very time consuming and the mechanisms of action are not clear. We developed a new, in situ, rapid, and sensitive fingerprinting approach, using surface-enhanced Raman spectroscopy (SERS), to study the antibacterial activity and mechanism of Ag NPs of 80 and 18 nm (Ag80 and Ag18, respectively), by using the strong electromagnetic enhancement generated by Ag NPs. Sensitive spectra changes representing various biomolecules in bacteria were observed with increasing concentrations of Ag NPs. They not only allowed SERS to monitor the antibacterial activity of Ag NPs of different sizes in different water media but also to study the antibacterial mechanism at the molecular level. Ag18 were found to be more toxic than Ag80 in water, but their toxicity declined to a similar level in the PBS medium. The antibacterial mechanism was proposed on the basis of a careful identification of the chemical origins by comparing the SERS spectra with model compounds. The dramatic change in protein, hypoxanthine, adenosine, and guanosine bands suggested that Ag NPs have a significant impact on the protein and metabolic processes of purine. Finally, by adding nontoxic and SERS active Au NPs, SERS was successfully utilized to study the action mode of the NPs unable to produce an observable SERS signal. This work opens a window for the future extensive SERS studies of the antibacterial mechanism of a great variety of non-SERS-active NPs.