APPLICATIONS OF CAPILLARY ELECTROCHROMATOGRAPHY IN PHARMACEUTICAL ANALYSIS

The operational parameters and factors which control the performance o f capillary electrochromatography (CEC) using commercially available C EC instrumentation are evaluated and discussed. The CEC of neutral or ion-suppressed acidic analytes shows marked advantages such as increas ed column efficiency and reduced analysis times compared to convention al high-performance liquid chromatography (HPLC). Development of the C EC method using C-18 stationary phases follows similar guidelines to t hat of HPLC and, due to the high efficiencies obtained, the time requi red for method development can be substantially reduced. The technique of CEC is extremely attractive for the analysis of pharmaceuticals du e to its excellent quantitative characteristics: good repeatability, r eproducibility, wide UV detector linearity, and excellent detection li mits. The analysis of acidic and neutral analytes by CEC using reverse -phase material is highly successful. However, in order to analyze hig hly basic analytes a strong cation exchange stationary phase is needed . This phase can produce staggering and as yet unexplained ''apparent' ' efficiencies of over 40 x 10(6) plates per meter; however, to-date t hese results are highly non-reproducible. The application of CEC to th e pharmaceutical industry has been demonstrated in the analysis of a w ide range of structurally diverse pharmaceutical compounds using capil laries packed with reverse-phase materials. (C) 1997 John Wiley & Sons , Inc.