Study Of Novel SERS Active Substrates And C₆₀ Modified Bilayer Lipid Membrane (BLM)

Empolying photons as probes, Raman spectroscopy is an ideal detective technique without damage directly related to the the vibrating spectrum of molecular structure, which is known as the fingerprint of material structures. Any tiny changes of structures can be sensitively reflected in Raman spectrum; therefore, Raman spectrum is widely used in physics, chemistry, life sciences of molecular structure, quality control, archaeology and so on. However, Raman signals are not easy to get due to the weak intensity. Therefore, the development of surface enhanced Raman Scattering (SERS) technique greatly enhances the scatting section, leading to the improvement of sensitiviry. Owing to the configuration of the SERS substrate's surface is a key factor for the appearance of SERS effect and the intensity of SERS singals(106-1014), so the substrate for the molecular's adsorbtion is very important. Therefore, the investigation of novel SERS active substrates is a hotspot for its extensive applications.Currently, there are many kinds of SERS-active substrares used in the wide range of SERS applications. Some examples are metal hydrosols (including gold, silver and copper colloid) and coarse surface with nano-scale using vacuum evaporation and mechanical polishment methords. But in practical applications, the above-mentioned SERS substrates have their own merits and defects and also limitness. The colloid prepared by reduction is easily obtained, but there are many disadvantages such as complex components, impurity and so on, which make it very difficult for its use to experiment systems and analysis for the results. The colloids gained by laser ablation are very pure, but the yield is not enough, either very expensive. Rough metal suface is normaly obtained by physical rubbing or chemical eroding. But there are also disadvantages such hangover, rudimental impurities, roughness difficult control and so on. So we want to investigate new kinds of SERS active substrates with a simple method and equipments, easily control, good repetition, broad applications and so on.By using pretreatment aluminum and copper foils deoxidizing silver nitrate solution we got the silver nano-structures with different surface morphology. SEM images indicate the reaction results are flowery and dendritic silver nanostructure. Through the investigation of surface enhanced Raman scattering (SERS) spectrum by p-hydroxybenzoic acid (PHBA) used as a probe molecule, it was found that the new system of the silver nanostructure is a highly efficient SERS active substrate whose SERS effect is even superior to the commonly used silver colloid system prepared by chemical method. Synchronously,the enhancement mechanism for the great enhancement of the new substrates is also discussed. The effect of SERS is condiered as a result of a combination of electromagnetic enhancement and chemical enhancement. Synchronously, it is anticipated this simple method can be extended to papare novel nanostructures of other metals which will help to extend the applications of SERS and furtherly used in the research fields of electronics, magnetics, catalyst, chemistry, biosensor, optics and micro-apparatus.Finally, we combine the Raman technique with electrochemistry method to study the spectroscopy characteristic of C60 embeded in bilayer lipid membrane supported by silver electrode (s-BLM). With precondition of good cycle volt-ampere (CV) curve so as to ensure the formation of favorable lipid membrane, simulatanetly, collect Raman signals and observe the change of Raman signals fore-and-aft the formation of bilayer lipid membrane(s-BLM). Using this new method we can study the reciprocity mechanism between C60 molecule and s-BLM and this will help to further discuss the sensor's mechanism of s-BLM decorated by C60.