Regulatory Assembly Of Noble Metal Nanorods SERS Substrates For Fabrication Of Drug Detection Module

Nowadays,the abuse of drugs has become an increasingly serious problem in public security.The situation in China is also severe and complex,the penetration and the production of drugs are becoming more and more serious.Faced with such a severe situation,drug detection plays an increasingly important role in combating drug crimes.Surface-enhanced Raman Spectroscopy(SERS)technique has been a powerful analytical tool since its discovery.It not only provided structural information of target molecules,but also attracted more and more attention with the advantages of high sensitivity,nondestructive property and fingerprint identification.Although it has been widely used in chemical detection,surface analysis and biological application,there are many problems in fast and quantitative drug detection,of which SERS substrate still faces challenges in the practical application.At present,the universal substrate in the laboratory was prepared under strict conditions with large cost,so it can not be applied in practical testing.Therefore,it is necessary to build a SERS substrate with low-cost,high sensitivity and reproducibility.In recent years,quantitative detection of SERS was attracted a lot of attention.The substrate construction with internal standard molecules of noble metal cavity structure as a strategy to solve the problem is proposed.Herein,in this thesis,considering the construction and application of the practical SERS substrate,we carried out the following parts:(1)This chapter presents a SERS substrates construction method based on self-assembled structure of gold nanorods.The self-assembled gold nanorods SERS substrates with dense uniformity can be obtained by reducing or removing the coffee ring effect by solvent evaporation-controlled assembly mechanism.We used the simulated climatic chamber to fix the environmental conditions and adjusted the surface properties of the silicon wafer,the re-dispersed concentration of the gold nanorods,and the dropping volume to prepare the substrate for gravity-induced solvent evaporation..Through the characterization of the substrates prepared under different parameters,the optimal parameters of the process were determined,and the SERS detection of the crystal violet with the substrate prepared by this process was highly sensitive and reproducible.(2)The second chapter is mainly based on the content of first chapter to further explore.It need to optimize the construction of the SERS substrate of the assembly structure from the point of view of field testing.We construct the substrate detection module which is suitable for the portable Raman spectrometer.The substrate module is simple,cheap,convenient and easy to carry.Combined with portable Raman spectroscopy and rapid pretreatment of drug-containing urine,the substrate can be used for drug SERS detection with high sensitivity and good reproducibility,which can be used in drug-related urine drug detection analysis.Moreover,it is expected to apply to the rapid detection of drug-related sites.(3)The last chapter is to design and construct a hollow Au/Ag nanorod with internal standard molecule,the preparation process of the materials was discussed and the detailed structure characterization was performed.The SERS detection was further systematically studied.CV as model molecule was used to explore the feasibility of the materials in quantitative detection,and then used it for SERS quantitative detection of drugs.The research shows that it has certain feasibility for SERS quantitative detection,which is a practical SERS substrate.