Shell-isolated nanoparticle-enhanced Raman spectroscopy
Shell-isolated nanoparticle-enhanced Raman spectroscopy
复制标题
DOI：
10.1038/s43586-023-00229-8
复制
发表时间：
2010-03
期刊：
影响因子：
64.8
通讯作者：
J. F. Li;Yi Fan Huang;Yong Ding;Zhi-Lin Yang;S. Li;Xiao Shun Zhou;F. Fan;Wei Zhang;Z. Zho
中科院分区：
文献类型：
--
作者：
J. F. Li;Yi Fan Huang;Yong Ding;Zhi-Lin Yang;S. Li;Xiao Shun Zhou;F. Fan;Wei Zhang;Z. Zho
表面增强拉曼散射(SERS)是一种强大的光谱技术，可以提供可与单分子荧光光谱相媲美的单分子水平的非破坏性和超灵敏的表征。然而，通常需要以银、金和铜等金属为衬底，表面粗糙或以纳米颗粒的形式来实现实质性的SERS效应，这严重限制了SERS的实际应用范围。许多方法已将该技术扩展到非传统衬底，最著名的是尖端增强拉曼光谱(TERS)，其中被探测物质(分子或材料表面)可以位于普通衬底上，衬底上方的纳米级金尖端充当拉曼信号放大器。缺点是来自尖端区域的总拉曼散射信号相当弱，因此将TERS的研究限制在具有大拉曼截面的分子上。在这里，我们报告了一种方法，我们称之为壳层隔离纳米颗粒增强拉曼光谱，其中拉曼信号放大是由具有超薄二氧化硅或氧化铝外壳的金纳米颗粒提供的。这种纳米颗粒的单层被作为“智能尘埃”散布在待探测的表面上。超薄的涂层防止纳米颗粒结块，将它们与被探测材料的直接接触隔开，并允许纳米颗粒符合不同的衬底轮廓。在铂、金单晶表面吸附的各种分子以及具有氢单分子膜的硅表面都获得了高质量的拉曼光谱。这些测量和我们对酵母细胞和含有农药残留的柑橘类水果的研究表明，我们的方法大大扩展了SERS在材料和生命科学以及食品安全、药物、爆炸物和环境污染物检测中的灵活性。
Surface-enhanced Raman scattering (SERS) is a powerful spectroscopy technique that can provide non-destructive and ultra-sensitive characterization down to single molecular level, comparable to single-molecule fluorescence spectroscopy. However, generally substrates based on metals such as Ag, Au and Cu, either with roughened surfaces or in the form of nanoparticles, are required to realise a substantial SERS effect, and this has severely limited the breadth of practical applications of SERS. A number of approaches have extended the technique to non-traditional substrates, most notably tip-enhanced Raman spectroscopy (TERS) where the probed substance (molecule or material surface) can be on a generic substrate and where a nanoscale gold tip above the substrate acts as the Raman signal amplifier. The drawback is that the total Raman scattering signal from the tip area is rather weak, thus limiting TERS studies to molecules with large Raman cross-sections. Here, we report an approach, which we name shell-isolated nanoparticle-enhanced Raman spectroscopy, in which the Raman signal amplification is provided by gold nanoparticles with an ultrathin silica or alumina shell. A monolayer of such nanoparticles is spread as ‘smart dust’ over the surface that is to be probed. The ultrathin coating keeps the nanoparticles from agglomerating, separates them from direct contact with the probed material and allows the nanoparticles to conform to different contours of substrates. High-quality Raman spectra were obtained on various molecules adsorbed at Pt and Au single-crystal surfaces and from Si surfaces with hydrogen monolayers. These measurements and our studies on yeast cells and citrus fruits with pesticide residues illustrate that our method significantly expands the flexibility of SERS for useful applications in the materials and life sciences, as well as for the inspection of food safety, drugs, explosives and environment pollutants.