纳米粒子修饰硅胶整体柱的制备及其在柱表面增强拉曼光谱应用研究

通过溶胶-凝胶法以四甲氧基硅烷(TMOS)和甲基三甲氧基硅烷(MTMS)作为混合的前体，聚乙二醇(PEG)为致孔剂，制备了具有贯通孔道结构的双孔硅胶整体柱，采用3-巯基丙基三甲氧基硅烷(MTPMS)对硅胶整体柱表面进行巯基化修饰后，分别将金、 银纳米粒子组装在整体柱材料表面。 利用透射电子显微镜(TEM)、 紫外-可见吸收光谱(UV-Vis)、 扫描电子显微镜(SEM)对金、 银纳米粒子形貌、 吸收光谱及组装金、 银纳米粒子前后整体柱的形貌进行了表征。 以对巯基苯胺(PATP)为探针分子，分别采用波长为633和532 nm的激发光作为激发光源，研究金和银纳米粒子修饰的硅胶整体柱的在柱表面增强拉曼光谱(SERS)性能。 结果表明，该基底呈现出很强的SERS活性，结合整体柱的分离富集优势将在食品/环境领域现场痕量检测方面具有广泛的应用前景。

Preparation of Nanoparticles-Modified Silica Monolith for on-Column Surface Enhanced Raman Spectroscopy

A novel silica monolith modified with Ag/Au nanoparticles was prepared for the on-column surface enhanced Raman spectroscopy (SERS). The bare monolithic silica column was prepared from in-situ co-condensation of tetraethoxysilane (TMOS) and methyl trimethoxysilane (MTMS) in the presence of polyethylene glycol (PEG) via a sol-gel process in the capillary, and was chemically modified with (3-mercaptopropyl) trimethoxysilane (MTPMS), followed by immobilization of Ag/Au nanoparticles. Transmission electron microscopy (TEM) and UV-Vis spectrometer were used to collect the TEM images and the extinction spectra of the nanoparticles colloid, respectively. Scanning electron microscope (SEM) was utilized to record the morphology of the silica monolith. The authros used p-aminothiophenol (PATP) as a probing molecule，and the SERS effect was investigated on Au/Ag nanoparticle-modified silica monolith under the excitation line of 633 and 532 nm, respectively. It is concluded that nanoparticle-modified silica monoliths will have broad application to the on-site detection of food and water contaminants in the field.