Applications Of Slurry-sampling/Ionic Liquid Extraction In Atomic Fluorescence Spectrometry

In this paper, hydride generation-atomic fluorescence spectrometry combined with slurry sampling, acid digestion and ionic liquids extraction, respectively, was used for for speciation analysis of Se in food and dietary supplements, and trace amounts of Cd in Baiyang lake water. The new, sensitive and effective methods were developed.This paper includes four chapters:Chapter one:The advancement of hydride generation atomic fluorescence spectrometry, speciation analysis of trace element, the application of slurry-sampling technique and ionic liquid extraction were reviewed with 41 references.Chapter two:A new method is developed for directly determination of total Se, inorganic Se and Se(VI) by slurry sampling-hydride generation atomic fluorescence spectrometry (SS-HGAFS). The total Se was extracted with HC1 and determined by SS-HGAFS. The inorganic Se and organic Se were separated by extracting with cyclohexane, Se(VI) in the aqueous phase were masked by Na2 SO3. The organic Se could be calculated by difference of the total Se and the inorganic Se, and the Se(IV) could be calculated by difference of the inorganic Se and the Se(VI). This method was used for the determination of total Se, inorganic Se and Se(VI) in rice flour, wheat flour,selenium-richen salt and dietary supplements.The proposed method has the characteristics of accuracy, facility,celerity and sensitivity, can be used for speciation analysis of selenium in real samples.Chapter three:Effective separation of organic selenium and inorganic selenium in selenium-enriched eggs was achieved by precipitating protein with trichloroacetic acid and extraction with cyclohexane, and a new method was established for the speciation of selenium by hydride generation-atomic absorption fluorescence spectrometry. The proposed method has been used for the determination of organic selenium, inorganic selenium and total selenium in selenium-enriched eggs. The content of organic selenium was 3-7 times that of inorganic selenium.Chapter four:The physicochemical performance of room-temperature ionic liquid and its application as extraction reagent in separation and concentration of metal ions were described. The research advancement for applications of room-temperature ionic liquid in flame atomic absorption, vapor generation atomic absorption, graphite furnace atomic absorption spectrometry and atomic fluorescence spectrometry as well as atomic emission spectrometry was reviewed. The 1-Butyl-3-MethylimidazoliumHexafluorophosphate was chosen as extractant for the extraction of Cd-dithizone.complex, Cd in water phase obtained by the anti-phase extraction from ionic liquid layer was was determined by hydride generation atomic fluorescence spectrometry.