| Elemental speciation analysis in environmental and biological samples is an interesting topic in analytical chemistry and arises much more attention to analytical scientists. The specific form in which an element occurs dictates its physico-chemical properties, its behavior in the environment, physiological function, its toxicity and essentiality for humans, animals or plants. For instance, Cr (â…¢) is an essential trace element for the proper functioning of living organisms. Cr (â…¢) is the important component of glucose tolerance factor, which can enhance the utilization of glucose and restrain the synthesis of fatty acid and cholesterin. On the contrary, Cr (â…¥) can incur pathological changes in liver and kidney, and has been considered as carcinogenic substance. Another example to illustrate the importance of speciation analysis is aluminum. Free Al3+, A1(OH)2+, Al(OH)2+and polymeric Al species have been found to be primarily responsible for Al aquatic toxicity, while Al-F and Al-Org can reduce or diminish toxicity among all Al species. The element species are rather complicated in environmental and biological system, they are easy to change with the alteration of the conditions, and what is more, the concentration of specific form of an element in real sample is much lower than its total amount. Therefore, how to rapidly and accurately obtain the elemental species information in environmental and biological samples is always one of the most challenging task to analytical scientists.The concentrations of Al and Cr in some environmental and biological samples are as low as ng/mL level, even much lower concentration may be found for a specific species. ICP-AES/MS has been proven to be one of the most powerful detection techniques for elemental speciation due to their excellent analytical performance, the combination of column separation techniques, such as micro-column separation technique, high-performance liquid chromatography, with ICP-MS has exhibited the greatest potentiality in the rapid and accurate speciation of trace elements in biological and environmental systems.It is well established that the use of matrix matching, internal standard and chemical separation can eliminate matrix effect and spectral interference in determination trace impurity in high purity rare earth oxides by ICP-MS. However, it suffered from some drawbacks such as, tedious, time consuming and large amount of sample required. Thus, a sensitive, rapid and reliable analytical method without matrix matching and internal standard for analysis of trace rare earth (RE) impurities in high purity RE oxides by ICP-MS is strongly required.The purpose of this dissertation is to develop new methods for the speciation ofAl and Cr in biological and environmental samples by combination of HPLC or nanometer-sized Zr2 micro-column separation with ICP-MS; to examine the spectral interference and matrix effect and to develop a simple and effective ICP-MS method for direct determination of RE impurities in high purity europium oxide without matrix matching and internal standard added.The major contents of this dissertation are described as follows:(1) An ODS column dynamically coated with zwitterionic bile acid derivative, 3-[(3-cholamidopropyl)-dimethylammonio]-l -propanesulfonate (CHAPS), was evaluated for direct injection HPLC-UV-ICP-MS determination of small molecules Al-complex compounds (Al-Cit) and large molecules Al-protein compounds (Al-Tf) in human serum. Under the optimal conditions, large-molecule Al-protein compounds and small molecules Al-complex compounds could be baseline separated in 2min, and both aluminum species were determined by ICP-MS. The experimental results show that the most of Al exist as Al-protein in human serum, the small amount of Al exist as small molecules Al-complex compounds. The detection limit of the method was 0.4 ng/mL with the RSD of 7%(n=11). Compared with the reported methods in the literature, this method has several attractive features such as simple, rapid, small sample required (10L)...
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