Lu Yilin, Yao Guohua, Sun Kexi, Huang Qing
Key Laboratory of Ion Beam Bioengineering, Institute of Technical Biology and Agriculture Engineering, Hefei Institutes of Physical Science, Chinese Academy of Sciences and Anhui Province, China.
Phys Chem Chem Phys. 2015 Sep 7;17(33):21149-57. doi: 10.1039/c4cp04904g. Epub 2014 Dec 5.
A new type of surface-enhanced Raman scattering (SERS) substrate consisting of β-cyclodextrin (β-CD) coated SiO2@Au@Ag nanoparticles (SiO2@Au@Ag@CD NPs) has been achieved. Our protocol was a simplified approach as the fabrication and modification of the silver shell were realized in a single-step reaction by taking advantage of β-CD as both the reducing and stabilizing agents. The as-synthesized SiO2@Au@Ag@CD NPs were uniform in size and demonstrated high SERS activity and reproducibility. The substrates consisting of the SiO2@Au@Ag@CD NPs were employed for SERS detection of polychlorinated biphenyls (PCBs) including PCB-3, PCB-29 and PCB-77. The SERS detection sensitivity was significantly improved due to enrichment of more PCB molecules captured by β-CD on the substrate surface, as confirmed by the appearance of the new Raman bands which are attributed to the complexes between β-CD and PCBs according to the theoretical simulation. Therefore, this work presents a novel approach to the fabrication of effective SERS substrates that can be employed for rapid determination of trace amounts of PCBs in the environment with high detection sensitivity and recognition selectivity.
一种由β-环糊精（β-CD）包覆的SiO₂@Au@Ag纳米粒子（SiO₂@Au@Ag@CD NPs）组成的新型表面增强拉曼散射（SERS）基底已被制备出来。我们的方案是一种简化方法，因为利用β-CD作为还原剂和稳定剂，在一步反应中实现了银壳的制备和修饰。所合成的SiO₂@Au@Ag@CD NPs尺寸均匀，具有高SERS活性和重现性。由SiO₂@Au@Ag@CD NPs组成的基底用于多氯联苯（PCBs）包括PCB-3、PCB-29和PCB-77的SERS检测。由于β-CD捕获的更多PCB分子在基底表面富集，SERS检测灵敏度显著提高，这通过新拉曼谱带的出现得到证实，根据理论模拟，这些谱带归因于β-CD与PCBs之间的络合物。因此，这项工作提出了一种制备有效SERS基底的新方法，该基底可用于以高检测灵敏度和识别选择性快速测定环境中痕量的PCBs。
