Chiral trace-element speciation in biological samples: present importance and application to speciation for seleno-amino acids

Abstract

Chiral trace-element speciation, the recognition of the particular enantiomer where the trace element sought is present, is restricted so far virtually to speciation of seleno-amino acids. The present importance of such studies, in general, and of chiral speciation, in particular, is highlighted in this article by comparing existing chiral speciation methods for seleno-amino acids. Usually these methods rely on hybrid techniques, where an adequate separation technique, such as high-performance liquid chromatography (HPLC) or gas chromatography (GC), is coupled on-line with element (selenium)-specific detection by inductively coupled plasma mass spectrometry (ICP-MS). Reported chiral speciation studies of seleno-amino acids in real biological samples, such as selenized yeast, are reviewed.