| It is necessary to establish a sensitive and rapid method for the speciation analysis of arsenic compounds because of widely use of arsenic compounds and the recognition of arsenic toxicity.The total arsenic content in environmental samples usually contains a few ug/L. Although there are many methods for arsenic speciation, UV, a routine detector, had low sensitivity while ICP-MS was not common used because of its expensive cost. Reference recent information, the HPLC-AFS technique was chosen as our research. Comparing with GC, HPLC, a common separation device, was more suitable to separate polarity arsenic compounds. AFS, had a high sensitivity, was a fairly cheap detector and it was suitable for common use. Thus, a technique of HPLC coupled with AFS has a high value of application. Li Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, the optimization of separate conditions of HPLC and determination conditions of AFS was established. The HPLC-AFS technique was established and it was successfully applied to the speciation and determination of arsenic compounds in different environmental and biological samples. This new technique was a convenient and reliable method, it was not only suitable for arsenic speciation but also suitable for elements which can form hydride compounds. In addition, it offered a theoretical and technical support for the development of civil apparatus thus made benefits for both society and economy. The main results in this thesis were as follows:1 Proposed a simple and sensitive method for the determination of total arsenic in sinters by hydride generation atomic fluorescence spectrometry (HGAFS). The linear range for Asv determination was 0~300 (ag/L. The method was validated by analyzing standard reference material and successfully applied to the determination of total arsenic in sinters with RSD less than 4%.2 A study has been conducted for the determination of arsenic species in plants using high performance liquid chromatoeraphy-atomic fluorescence spectrometry with emphasis on sample extraction procedures. The method was optimized with respect to selection of extraction solvent, extraction time and the extraction steps. Finally methanol-water(2:l), 20min shaking and 3 times were chosen for extractionarsenic species in plants. The linearity of the calibration curves and the LODs were as follows: As111, 0.9995 and 0.4 jag L'1; Asv, 0.9998 and 1.6 ug L'1; MMA, 0.9965 and 1.6 ng L"1; DMA, 0.9993 and 1.9 ng I/1. The analytical procedure was validated by analyzing certified reference material GBW 82301 (peach leaves) and was successfully applied to the arsenic speciation in plants. The results showed that inorganic arsenic species (As11 and Asv) were the major ones as well as organic arsenic species (MMA and DMA) existed hi plants at low concentration.3 Inorganic arsenic species (As111 #3 Asv) in Guanting reservoir and its downrivers were separated by anion exchange chromatography and determinated by atomic fluorescence spectrometry. Except in one sample, both As11 concentration and Asv concentration in other samples were less than 4 p.g/L.4 The total contents of arsenic and selenium in coals were reported. HGAFS was based on the oxidation of coals with strong acid mixtures in the pressure steel bomb. For arsenic, it can be determined after oxidizing to Asv while for selenium, it have to be reduced to SeIV with 6 mol/L HC1 after oxidizing to SeVI because the reduction of Sevl to SeIV is a slow process while the generation of Se hydride is a very fast procedure. The LODs of Asv and Seivwere O.Sug L"1 and 0.6u.g L'1 respectively. The method was validated by analyzing standard reference material (coal fly ash) with satisfactory results and was successfully used for the determination of arsenic and selenium in coals.5 Conducted the first small-scale investigation and determination of arsenic contents in some Chinese wines and beers by HGAFS after oxidation with HNOa and H2O2. The recovery were 96.79?.30% (n=9). Since China has no legi...
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