The Preparation Of Surface-enhanced Raman Scattering Active Substrate And Its Immunoassay Research

Since the surface-enhanced Raman scattering (SERS) phenomenon was discovered, SERSspectroscopy has been widely applied in various disciplines such as biomedicine, analyticalchemistry, environmental science because of the unique advantages of SERS spectroscopy, i.e.,high sensitivity, without destroy for sample, sample preparation simpleness and providing thecharacteristic fingerprint peaks of sample. It is well known that the intensity of the SERS signal isdependent on the performance of the SERS-active substrate, so it is very significant for theapplication of SERS spectroscopy to prepare SERS-active substrate with strong ability of signalenhancement, stability and reproducibility.In our study, the SERS-active substrate were prepared, characterized and carried out inimmunoassay research. It is found that the prepared SERS-active substrate have exhibited excellentpreformance in detection range, application condition and sensitivity, and its application is werywide.And this thesis is divided into four chapters. In the first chapter, we sketched the enhancementmechanism of SERS, generalize the research status and the preparation method of SERS-activesubstrate, and the application status of SERS spectroscopy in biology. In the second chapter, thechemical reduction method have been used to prepare gold/silver nanoparticles through thereduction of Au/Ag ions on the surface of the silicon wafer, and the gold/silver nanoparticlesmodified silicon as SERS-active substrate. Meanwhile the self-assembly of gold nanoparticles atthe oil-air interfaces have been used to prepare the gold nanoparticles micrometer ring as theSERS-active substrate. Then we characterize the performance of the prepared SERS-activesubstrate and research the SERS effect of the SERS-active substrate. The experimental resultshown that the prepared SERS-active substrate have strong ability of signal enhancement, stabilityand reproducibility, and the SERS enhancement factor is3.6×108. In the third chapter, theapplication of SERS spectroscopy in biology have been researched. The nano-Au immune probesand the nano-Ag immune substrate have been prepared, and then use them to assay theapolipoprotein B with a range of concentration from200pg/mL to2fg/mL, and the detection limitis as low as2fg/mL. In the contrast experimental, the apolipoprotein A1, as a contrast proteininstead of apoB, was used examined and certified the the immunologic specificity of the SERS-based immunoassay, and The results demonstrated that the SERS-based have high immunologicspecificity. Finally, we summarized our research work and potentially developments of the workare given.