| Summary: | 碩士 === 國立中山大學 === 化學系研究所 === 102 === Abstract
Chemical vapor generation（CVG）is a powerful sample introduction technique, which is used for inductively coupled plasma mass spectrometry（ICP-MS）to improve sensitivity and to eliminate matrix effect. Analytes can be transformed to hydride or elemental vapor through chemical reaction. The gaseous analytes have higher transport efficiency than pneumatic nebulizer, therefore it has the better sensitivity and lower detection limit. CVG system can separate analytes from matrix by a gas-liquid separator, so it can avoid spectral and non-spectral interferences caused by matrix elements.
First research is using slurry sampling as pretreatment, and to determine Ge, As, Cd, Sb, Hg and Bi in creams by FIA-CVG-ICP-MS. The cream slurry containing 2% m/v cream, 2% m/v Thiourea, 0.05% m/v L-cysteine, 0.5 μg L-1 Co(II) and 1.2% v/v HCl. The quantifications have been carried out using standard addition and isotope dilution methods. The influences of vapor generation conditions on the analyte signals were reported. This method has been applied for the determination of Ge, As, Cd, Sb, Hg and Bi in cream samples obtained from the local markets. The analytical results of cream cosmetics certified reference material（GBW09305）determined by standard addition and isotope dilution methods were in a good agreement with ETV-ICP-MS and those of digested samples analysed by pneumatic nebulization ICP-MS. Under the optimum operating conditions, the detection limit obtained from the standard addition curve was in the range of 0.02-0.45 ng g-1 for Ge, As, Cd, Sb, Hg and Bi, respectively, in the cream samples.
Second research is using slurry sampling as pretreatment, and to determine Pb in lipsticks by FIA-CVG-ICP-MS. The lipstick slurry containing 1% m/v cream, 0.5 m/v K3Fe(CN)6 and 0.5% v/v HNO3. The quantifications have been carried out using standard addition and isotope dilution methods. The influences of vapor generation conditions on the Pb signal were reported. This method has been applied for the determination of Pb in lipstick samples obtained from the local markets. The analytical results of cream cosmetics certified reference material（GBW09305）determined by standard addition and isotope dilution methods were in a good agreement with those of digested samples analysed by pneumatic nebulization ICP-MS. The method provided good reproducibility and the best detection limit was found to be 0.11 ng g-1 in the cream sample.
Key word: CVG, ICP-MS, Isotope dilution, Creams, Lipsticks
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