ABSTRACT
I. INTRODUCTION Separations in electrical fields have been successfully applied to analytical problems in the biological sciences throughout the twentieth century, and the principle of moving charged particles by electricity has been known for almost two centuries. As early as in 1807 Reuss communicated his observations on the effects of electrical fields on colloid clay particles suspended in a solution (published in 1809 [1]). Faraday and Du Bois-Reymond characterized the phenomenon in more detail later in the same century [2], and Michaelis coined the term electrophoresis in 1909 [3]. The foundations of electrophoretic separations in tubes were subsequently laid in Scandinavia by Arne Tiselius and later by Stellan Hjertén and Rauno Virtanen [4-6]. Tiselius in his early work on moving boundary electrophoresis discussed the following features: (a) online detection by ultraviolet light of analytes moving in transparent quartz capillaries; (b) the increase in separation efficiency with increase in field strengths; and (c) the realization of this in the efficient heat-dissipating format of capillaries [7,8]. Even though Tiselius and his colleagues and their successors in the moving boundary electrophoresis field for technical reasons used schlieren optics of refractive index gradients for detection as wells as large U-tubes made of glass and relatively low field strengths, the features outlined by Tiselius are in fact the basis of contemporary capillary electrophoresis (CE).
