Capabilities and limitations of gel electrophoresis for elemental speciation: A laboratory’s experience*

Gel electrophoresis is a fractionation/separation technique that yields valuable information in the field of metalloproteomics, often referred to as metallomics. This paper is based on four years of practical experience of the authors’ lab in this domain and highlights the capabilities and limitations of gel electrophoresis. Pitfalls of the technique were recognized by identifying the origin of artefacts in the separation, species degradation being the most important. Gel electrophoresis can be accomplished under either native or denaturing conditions. The speciation of vanadium and selenium among serum and yeast proteins, respectively, is used to illustrate these two major modes. The most powerful approach is twodimensional denaturing gel electrophoresis. This review of the methods used in our laboratory also describes the application of the two major detection techniques, autoradiography on the one hand and electrothermal vaporization—or laser ablation (LA)—inductively coupled plasma–mass spectrometry (ICP–MS) on the other.