Capillary Zone Electrophoresis

Abstract

SUMMARY Capillary electrophoresis offers the possibility of rapid and effective separations in an instrumental format. The two most serious obstacles for future development are the present insufficient detector sensitivity and residual adsorption of solutes to the capillary surface. Capillaries offer some advantages over traditional gel systems. Efficient heat dissipation from capillaries permits the application of unusually high voltages which results in fast and efficient separations. On-line sample injection and detection along with the reusable nature of capillaries makes this format suitable for automation. This could be a significant advantage in situations where repetitive analyses must be run. Capillaries lend themselves to collection of accurate physico-chemical data such as mobilities from migration times and diffusion coefficients from zone widths. They are also an ideal system in which to investigate non-aqueous separation media (ref. 14). Forming gels in a variety of non-aqueous solvents might be difficult, and capillaries offer an uncomplicated approach to the problem. Non-aqueous solvents, although not traditional in electrophoresis, offer exciting possibilities. The wider range of acid and base strengths possible in solvents other than water, as well as the ability to solvate very hydrophobic solutes, could greatly expand the range of substances amenable to electrophoretic separation and analysis.