Metabolites organic trace analysis

Ion chromatography plays a prominent role in the characterization of pharmaceutically relevant compounds predominantly in the early stages of research. This includes the trace analysis of impurities and metabolites, the elemental analysis and structural elucidation of counter ions. These counter ions are often inorganic anions such as chloride and bromide or organic acids such as acetate, methyl sulfate, and trifluoroacetate. 

Figure 3. HPLC Analysis of Ginsenosides. Ginsenosides were isolated from spent broth in which either no organism (upper trace), Trichoderma hamatum (middle trace) or Pythium irregulare (lower trace) had been cultured for five days at 25 °C in the dark. Ginsenosides were chromatographed on a Microsorb-MV C-18 column (150 x 4.6 mm, 5 mm) using an acetonitrile H20 gradient (Nicol et al., 2002), and detected at 203 nm. The in the lower trace indicates the unknown metabolite found in the spent broth of Py. irregulare.

In the late 1970s HPLC provided an ideal tool for the analysis of pollutants and other environmental contaminants. Techniques were developed for analyzing chlorophenols, pesticide residues, and metabolites in drinking water and soil (parts per trillion) and trace organics in river water and marine sediments, and for monitoring industrial waste water and polynuclear aromatics in air. Techniques were also developed for determining fungicides and their decomposition products and herbicide metabolites in plants and animals. 

In the last years, the intensive agriculture has highlighted the need of procedures to study the presence of pollutants in crops and foodstuffs and other environmental matrices (Marco et al., 1996 Kramer, 1996). Pesticides and their metabolites have received particular attention during the last few years in environmental trace-organic analysis. 

This type of detector is used for the detection and determination of very small quantities of substances with high electron affinities. In the trace range, the ECD is employed amongst other things for the analysis of traces of pesticides, nitro compounds, ozonides, chemical poison gases, pharmaceuticals, carcinogens, metabolites and metallo-organic compounds. 

Analytical chemistry is important in practically all areas of human endeavor and in all spheres of the environment. Industrial raw materials and products processed in the anthrosphere are assayed by chemical analysis, and analytical monitoring is employed to monitor and control industrial processes. Hardness, alkalinity, and trace-level pollutants (see Chapters 3-5) are measured in water by chemical analysis. Nitrogen oxides, sulfur oxides, oxidants, and organic pollutants (see Chapters 6-8) are determined in air by chemical analysis. In the geosphere (see Chapters 9-11), fertilizer constituents in soil and commercially valuable minerals in ores are measured by chemical analysis. In the biosphere, xenobiotic materials and their metabolites (see Chapters 2 and 12) are monitored by chemical analysis. As discussed further in this chapter, analytical chemistry is very important in the area of occupational health and the practice of industrial hygiene. 

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