Studies On The Speciation Analysis Of Mercury, Arsenic And Antimony In Traditional Chinese Medicine By Atomic Fluorescence Spectrometry

The studies of speciation analysis of mercury, arsenic and antimony in Traditional Chinese Medicine by atomic fluorescence spectrometry are described in this disertation, which consists of six chapters.Chapter one: The recent progress of the application of hydride generation-double channel atomic fluorescence spectrometry and the speciation analysis of elements in Traditional Chinese Medicine has been reviewed with the relative references of 88.Chapter two: A method has been described for the determination of mercury by vapor generation-atomic fluorescence spectrometry. The experimental conditions that influence the atomic fluorescence signal intensity were investigated and optimized, and the influence from foreign ions and the elimination were studied. Thiourea-citric acid-ferrite ion was selected as enhancement reagent. The detection limit and relative standard deviation were of 5.748jj,g/L and 1.56 %, respectively. The proposed method was applied to the determination of mercury in six kinds of Traditional Chinese Medicines with a recovery range of 90.4-109.6%.Chapter three: A sensitive method has been proposed for the determination of inorganic mercury and total organic mercury in Traditional Chinese Medicine by vapor generation-atomic fluorescence spectrometry. The experimental conditions that influence the atomic fluorescence signal intensity of Hg and the oxidization of organic mercury were investigated and optimized. Thiourea-citric acid was selected as sensitization reagent. The influence from foreign ions and their elimination were studied. The detection limit of the method for Hg was of 7.611 ng/L and the relative standard deviation was 1.24%. The proposed method was successfully applied to the speciation analysis of mercury in the real samples with a recovery range of 90.3-110.3%.Chapter four: A method has been described for the simultaneous determination of As(III), As(V), Sb(III) and Sb(V) in Traditional Chinese Medicines by hydride generation-double channel atomic fluorescence spectrometry. The experimental conditions that influence the fluorescence intensities of arsenic and antimony wereinvestigated and optimized, and the influence from foreign ions and the eliminations were studied. The detection limits were found to be 90.31 ng/L and 57.82 ng/L for arsenic and antimony, respectively. The proposed method was applied to the determination of arsenic and antimony species in seven kinds of Traditional Chinese Medicines. Recoveries were in the ranges of 90.1%~105.0%, 89.2%~102.0%, 89.7%~102.0% and 90.3%~110.0% for As(III), As(V), Sb(III) and Sb(V), respectively.Chapter five: A method has been described for the determination of arsenic species by hydride generation-atomic fluorescence spectrometry using separation technique with sulphhydryl cotton fiber (SCF). In a medium of 1 mol/L HC1, As(III) can be adsorbed by SCF and separated from As(V). The experimental conditions that influence the atomic fluorescence signal intensity and the reduction of As(V) were investigated and optimized. The influence from foreign ions and the elimination were studied. The detection limit of 64.31 ng/L, relative standard deviations of 1.12% and a recovery range of 90.2%~116.3% were obtained. The proposed method was applied to the speciation analysis of arsenic in five kinds of Traditional Chinese Medicines.Chapter six: A method has been described for the simultaneous determination of mercury and arsenic by vapor generation-double channel atomic fluorescence spectrometry. The experimental conditions that influence the atomic fluorescence signal intensities of Hg and As were investigated and optimized. Thiourea-citric acid-ferric ion was selected as enhancement reagent. The influence from foreign ions and the elimination were studied. The detection limits of this method for Hg and As were of 21.10 ng/L and 103.1 ng/L, respectively. Relative standard deviations of 2.01% and 2.39% for Hg and As, respectively, were obtained under optimum conditions. The proposed method was applied to the determination of mercury an...