Study On Determination Of Some Drugs By Surface-Enhanced Raman Spectroscopy

Surface-enhanced Raman scattering （SERS） can provide greatly enhanced Ramansignals of analytes that have been adsorbed onto specially prepared metal surfaces.This remarkable enhancement provides high sensitivity and gives an opportunity forthe development of ultra-sensitive analytical methods. As the small portableinstrumentation developing, makes this technique ideal for both qualitative andquantitative applications. Not only the SERS is used as quantitative tool, but also givechemical information on the molecular structure in a nondestructive manner. Thequalitative and quantitative information can be obtained at the same time. Based on theSERS some drugs were determined using collioid nanoparticles as substrates. Thethesis mainly includes two parts: determination of mesna in the pharmaceuticalpreparations and determination of thiram in the environmental water.Gold colloid was used as SERS substrates to determine2-mercaptoethanesulfonate（mesna）. In order to achieve the optimal SERS signals, the influence of experimentalparameters were examined. Under the optimum conditions, the SERS intensity isproportional to the concentration of mesna in the range of9.0×10^-8to9.0×10^-7mol/L.The corresponding correlation coefficient of the linear equation is0.996. The realsamples were analyzed. The recoveries of the analyte are from86.7to106.7%and theRSDs are lower than4.2%, which indicates that the proposed method is believable andsatisfactory.Au/Ag core/shell bipyramids were used as SERS substrates to determine the thiram.The metallic substrates show high SERS performance and are very suitable for theanalytical sensors. The fabrication and characterization of the Au/Ag core/shellbipyramids were described. The influence of experimental parameters, such as thethickness of Ag shell of the bipyramids, sodium chloride concentration and pH valueon SERS of thiram was examined and optimized. Under the optimum conditions, the SERS intensity is proportional to the concentration of thiram in the range of3.3to400.0μg/L. The corresponding correlation coefficient of the linear equation is0.997.The limit of detection for thiram is2.0μg/L. The recoveries of the thiram in the fourreal water samples are between67.83%and110.7%and the RSDs are between0.7%and5.98%. These results show that recoveries of thiram and the reproducibility aresatisfactory.