Coupling continuous separation techniques to capillary electrophoresis

One of the weak points of capillary electrophoresis is the need to implemen t rigorously sample pretreatment because its great impact on the quality of the qualitative and quantitative results provided. One of the approaches t o solve this problem is through the symbiosis of automatic continuous flow systems (CFSs) and capillary electrophoresis (CE). In this review a systema tic approach to CFS-CE coupling is presented and discussed. The design of t he corresponding interface depends on three factors, namely: (a) the charac teristics of the CFS involved which can be non-chromatographic and chromato graphic; (b) the type of CE equipment: laboratory-made or commercially avai lable; and (c) the type of connection which can be in-line (on-capillary), on-line or mixed off/on-line. These are the basic criteria to qualify the h yphenation of CFS (solid-phase extraction, dialysis, gas diffusion, evapora tion, direct leaching) with CE described so far and applied to determine a variety of analytes in many different types of samples. A critical discussi on allows one to demonstrate that this symbiosis is an important topic in r esearch and development, besides separation and detection, to consolidate C E as a routine analytical tool. (C) 2001 Elsevier Science B.V. All rights r eserved.