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E. Rosenberg:
"Speciation Analysis: A Cross-Sectional Discipline Between General Chemistry, Environmental Analysis and Life Sciences";
Vortrag: Universität Salzburg, Universität Salzburg, Fakultät für Biochemie (eingeladen); 16.05.2007.

Speciation analysis has for many years challenged analytical chemists, prompting them to design new and more sensitive methods and instrumentation for the determination of organometallic species, once that it has been recognised that it is not the total element concentration but rather the specific chemical form (= species) in which an element occurs that determines its toxicity or beneficial effect, its physiological effect or environmental fate [1]. The particular difficulties of analysing elemental species are due to the low concentrations at which they typically occur, the lability of certain species, calling for very judicious sample preparation techniques to maximise extraction efficiencies while minimising analyte decomposition, and finally the unavailability of many relevant species as reference substances in pure form.
Much of the early work in speciation analysis has focused on the quantitative determination of few well-known, low molecular weight species of environmental relevance, such as organolead, organotin or organomercury compounds. The development of reliable analytical methods for the low concentration levels encountered in the complex environmental matrices was the biggest challenge in this context. Methods for this type of speciation analysis are well established now and can successfully be performed in expert labs. Consequently, research in speciation analysis has turned now to other fields such as pharmaceuticals, "nutraceuticals" (= nutritional additives with health-supporting effects) or to the analysis of metalloproteins or other metal-binding biomolecules. It is evident that this change of scope of speciation analysis was stipulating a change in analytical methodology: No longer were hyphenated techniques with element-specific detection such as the atomic emission detector (GC-AED) the most valuable tool to perform speciation analysis, but mass spectrometry (coupled to gas or liquid chromatography) proved to be the more versatile technique in this context. This development will be critically discussed and illustrated by examples from own work. Specific attention will be given to Germanium speciation as this element has recently attracted great interest as particular organic compounds of Germanium are claimed to act as chemopreventive agent against cancer. Various analytical approaches will be presented for the speciation analysis of Germanium sesquioxide (the currently most used Ge drug) and discussed with their merits and pitfalls. An outlook will be given on the potential future progress and development of this specialised field of analytical chemistry that is at the intersection of life sciences, environmental chemistry and general chemistry.

[1] L. Ebdon, L. Pitts, R. Cornelis, H. Crews (Eds.), Trace Element Speciation for Environment, Food and Health, Royal Society of Chemistry, Cambridge, UK (2001)