Capillary electrophoresis

This chapter describes electrophoresis, a separating technique used in capillary format or in microsystems, and its coupling with inductively coupled plasma mass spectrometry (ICPMS). Electrophoresis is based on the differences in the migration velocities of charged species, from small inorganic ions to biological macromolecules, in an electric field. Capillary electrophoresis (CE) offers unique separation capabilities, such as high efficiency and resolution, rapidity (especially in microsystems), and very low sample consumption. Thanks to the development of interfaces with ICPMS, which is particularly sensitive and selective, the CE technique has evolved dramatically and has made its entry into the field of speciation analysis. Following a discussion of the principles of this electromigration technique and of the influence of the main parameters affecting its performance, special attention will be given to instrumentation and particularly to interfaces with ICPMS instruments. Quantification performance will then be described. Representative examples will finally illustrate the numerous applications of CE-ICPMS in areas such as the environment, life sciences, and nuclear energy, in order to point to current and future trends with this technique.