ANALYSIS FOR METALLOTHIONEINS USING COUPLED TECHNIQUES

Analytical chemistry of metallothioneins based on the coupling of a hi gh resolution separation technique with an element or species selectiv e detection technique is discussed. The role of size-exclusion chromat ography (SEC) with on-line atomic spectrometric detection for the quan tification of metallothionein fraction in cell cytosols is evaluated. Particular attention is given to the conditions for the separation of metallated metallothionein isoforms (MT-1, MT-2, MT-3) and sub-isoform s within these classes by anion-exchange and reversed-phase HPLC. Tech niques for interfacing chromatography with atomic absorption spectrome try (AAS), inductively coupled plasma atomic emission spectrometry (IC P AES) and ICP mass spectrometry (MS) are assessed. The potential of e lectrospray (tandem) mass spectrometry for the characterization of met allothionein isoforms with respect to molecular mass and aminoacid seq uence is highlighted. Perspectives for capillary zone electrophoresis (CZE), microbore and capillary HPLC with ICP MS and electrospray MS(/M S) detection for the probing of metallothioneins are discussed. Applic ations of hyphenated techniques to the analysis of real-world samples are reviewed. (C) 1998 Elsevier Science B.V. All rights reserved.