Nie S, Emory SR
Department of Chemistry, Indiana University, Bloomington, IN 47405, USA.
Science. 1997 Feb 21;275(5303):1102-6. doi: 10.1126/science.275.5303.1102.
Optical detection and spectroscopy of single molecules and single nanoparticles have been achieved at room temperature with the use of surface-enhanced Raman scattering. Individual silver colloidal nanoparticles were screened from a large heterogeneous population for special size-dependent properties and were then used to amplify the spectroscopic signatures of adsorbed molecules. For single rhodamine 6G molecules adsorbed on the selected nanoparticles, the intrinsic Raman enhancement factors were on the order of 10(14) to 10(15), much larger than the ensemble-averaged values derived from conventional measurements. This enormous enhancement leads to vibrational Raman signals that are more intense and more stable than single-molecule fluorescence.
利用表面增强拉曼散射，在室温下实现了单分子和单纳米颗粒的光学检测与光谱分析。从大量异质群体中筛选出具有特殊尺寸依赖性性质的单个银胶体纳米颗粒，然后用于放大吸附分子的光谱特征。对于吸附在所选纳米颗粒上的单个罗丹明6G分子，其固有拉曼增强因子在10(14)至10(15)的量级，远大于传统测量得到的总体平均值。这种巨大的增强导致振动拉曼信号比单分子荧光更强烈、更稳定。
