Etchegoin Pablo G, Le Ru Eric C, Meyer Matthias
The MacDiarmid Institute for Advanced Materials and Nanotechnology, School of Chemical and Physical Sciences, Victoria University of Wellington, P.O. Box 600, Wellington, New Zealand.
J Am Chem Soc. 2009 Feb 25;131(7):2713-6. doi: 10.1021/ja808934d.
We report on the observation of the natural isotopic spread of carbon from single-molecule surface-enhanced Raman spectroscopy (SM-SERS). By choosing a dye molecule with a very localized Raman-active vibration in a cyano bond (C[triple bond]N triple bond), we observe (in a SERS colloidal liquid) a small fraction of SM-SERS events where the frequency of the cyano mode is softened and in agreement with the effect of substituting (12)C by the next most abundant isotope, (13)C. This example adds another demonstration of single-molecule sensitivity in SERS through isotopic editing, which in this case is done not by artificial isotopic editing but rather by nature itself. It also highlights SERS as a unique spectroscopic tool that is capable of detecting an isotopic change in one atom of a single molecule.
我们报告了通过单分子表面增强拉曼光谱（SM-SERS）对碳的自然同位素分布的观察。通过选择一种在氰基键（C≡N三键）中具有非常局域化拉曼活性振动的染料分子，我们观察到（在SERS胶体液体中）一小部分SM-SERS事件，其中氰基模式的频率变软，并且与用下一个最丰富的同位素（13）C取代（12）C的效果一致。这个例子通过同位素编辑增加了SERS中单分子灵敏度的另一个证明，在这种情况下不是通过人工同位素编辑而是由自然本身完成的。它还突出了SERS作为一种独特的光谱工具，能够检测单个分子中一个原子的同位素变化。
