This paper reviews the application of CE to the analysis of small-molecule pharmaceuticals. The areas of pharmaceutical analysis covered are enantiomer separation, the analysis of small molecules such as amino acids or drug counter-ions, pharmaceutical assay, determination of related substances and physicochemical measurements such as log P and pK(a) of compounds. The different electrophoretic modes available and their advantages for pharmaceutical analysis are described. Recent applications of CE for each subject area are tabulated with electrolyte details.

Microemulsion electrokinetic chromatography (MEEKC) is an electrodriven separation technique. Separations are typically achieved using oil-in-water microemulsions, which are composed of nanometre-sized droplets of oil suspended in aqueous buffer. The oil droplets are coated in surfactant molecules and the system is stabilised by the addition of a short-chain alcohol cosurfactant. The novel use of water-in-oil microemulsions for MEEKC separations has also been investigated recently. This report summarises the different microemulsion types and compositions used to-date and their applications with a focus on recent papers (2002-2004). The effects of key operating variables (pH, surfactant, cosurfactant, oil phase, buffer, additives, temperature, organic modifier) and methodology techniques are described.

The migration behaviour of nicotine and related tobacco alkaloids was investigated using three different capillary electrophoretic (CE) modes. Novel separations were achieved both using microemulsion electrokinetic chromatography (MEEKC) and nonaqueous CE (NACE). Improved resolution compared to previous studies was obtained using free-solution CE (FSCE). Each technique resulted in different, orthogonal separation selectivity. The suitability of each method for application to the analysis of nicotine lozenges is discussed. The FSCE method was applied to the analysis of nicotine lozenges due to its compatibility with an established lozenge extraction solvent. The method used gave good injection precision and linearity. Good agreement of CE and high-performance liquid chromatography (HPLC) results was obtained. The CE method is therefore considered suitable for the quantitative determination of nicotine in nicotine lozenges.