纳米粒子体系中染料分子的表面增强拉曼光谱

Surface-Enhanced Raman Spectrum of Dye Molecules in Nanoparticle Systems

用化学还原的方法制得银胶体,并加入酒精或腺嘌呤(A)使其聚集,以聚集的银胶体作为表面增强拉曼散射的衬底。分别用原子力显微镜和紫外分光光度计来检测银胶体聚集前后的表面形貌和吸收光谱。以罗丹明B(RhB),罗丹明6G(R6G)作为探针分子测定衬底的表面增强拉曼散射效应。结果表明,在同一衬底上,RhB的拉曼灵敏度大约是R6G的2倍。RhB在腺嘌呤引起银胶体聚集形成的衬底表面的拉曼灵敏度比在酒精引起银胶体聚集形成的衬底表面的拉曼灵敏度高。由此可知腺嘌呤引起银胶体聚集的SERS衬底上的"活性点"比酒精引起银胶体聚集的衬底上的"活性点"活跃。

We prepare silver nanoparticles colloids by reducing silver nitrate with sodium borohydride. We also investigate their spectral properties and morphology with silver nanoparticles aggregation as substrates by ultraviolet and visual absorption spectroscopy and atomic force microscopy. We employ rhodamine B （RhB） and rhodamine 6G （R6G） to determine the SERS activity on these substrates of 10^-7 mol/L . Experimental results show that the SERS sensitivity of RhB is two times that of R6G on an identical substrate, and that the SERS sensitivity of RhB of the substrate formed by DNA induced silver nanoparticles aggregation is higher than that of the substrate formed by ethanol induced silver nanoparticles aggregation. Experimental results show that the SERS sensitivity of RhB is two times that of R6G on an identical substrate, and that the SERS sensitivity of RhB of the substrate formed by DNA induced silver nanoparticles aggregation is higher than that of the substrate formed by ethanol induced silver nanoparticles aggregation.