Advances in analytical methodology for bioinorganic speciation analysis: metallomics, metalloproteomics and heteroatom-tagged proteomics and metabolomics

The recent developments in analytical techniques capable of providing information on the identity and quantity of heteroatom-containing biomolecules are critically discussed. Particular attention is paid to the emerging areas of bioinorganic analysis including: (i) a comprehensive analysis of the entirety of metal and metalloid species within a cell or tissue type (metallomics), (ii) the study of the part of the metallome involving the protein ligands (metalloproteomics), and (iii) the use of a heteroelement, naturally present in a protein or introduced in a tag added by means of derivatisation, for the spotting and quantification of proteins (heteroatom-tagged proteomics). Inductively coupled plasma mass spectrometry (ICP MS), used as detector in chromatography and electrophoresis, and supported by electrospray and MALDI MS, appears as the linchpin analytical technique for these emerging areas. This review focuses on the recent advances in ICP MS in biological speciation analysis including sensitive detection of non-metals, especially of sulfur and phosphorus, couplings to capillary and nanoflow HPLC and capillary electrophoresis, laser ablation ICP MS detection of proteins in gel electrophoresis, and isotope dilution quantification of biomolecules. The paper can be considered as a followup of a previous review by the author on a similar topic (ref. 1: J. Szpunar, Analyst, 2000, 125, 963).