Multielement profiling analyses of biological, geochemical, and environmental samples as studied by analytical atomic spectrometry

The progress of modern analytical atomic spectrometry is briefly reviewed with emphasis on ICP-AES and ICP-MS; these provide some excellent analytical features such as high sensitivity, wide linear dynamic range, and multielement detection capability. Thus, the multielement determination of the major-to-ultratrace elements from % to sub-ppt (1 ppt = 10(-12) g ml(-1)) level is possible for the biological, geochemical, and environmental samples. The standard or certified reference materials of plant, human blood serum, and the other biological samples were analyzed to establish the reliable analytical methods for the multielement determination by ICP-AES and ICP-MS. The modern analytical methods were applied to: (i) the correlation analysis of the elements in human blood serum, and (ii) the determination of rare earth elements in human blood serum on a personal basis. The speciation of trace elements in natural water was also carried out by the SEC (size exclusion chromatography)/UV absorption detection/ICP-MS combined system after ultrafiltration of the water samples. The SEC chromatograms indicated that most of trace elements in natural water existed as large organic molecule-metal complexes with the molecular weight of > 300000 and 10000-50000. In addition, trace elements in man and in the sea were discussed from the viewpoints of the geochemical classification of the elements on the earth, the Lewis's acid-base theory, and the principle of HSAB (hard and soft acids and bases). Such multielement information allows the multielement profiling analyses of various samples to elucidate the elemental distributions, physicochemical characteristics, and behaviors of the major-to-ultratrace elements in relation with the biological functions or with the geochemical and environmental phenomena.