We describe here the state-of-the-art development of on-line capillary electrophoresis-mass spectrometry (CE-MS) over the last two years. Technological developments included are novel designs of new interfaces and ionization sources, new capillary coatings, buffers, and micelles as well as application of various modes of CE-MS published in the recent literature. The areas of CE-MS application in analysis of small achiral and chiral solutes are covered in sections that highlight the recent advances and possibilities of each mode of CE-MS. Application areas reviewed in this paper include achiral and chiral pharmaceuticals, agrochemicals, carbohydrates, and small peptides. The separation of enantiomers using micellar electrokinetic chromatography (MEKC)-MS with molecular micelles and capillary electrochromatography (CEC)-MS using pack tapered columns appears to provide good tolerance to electrospray stability for routine on-line CE-MS. These two modes seem to be very suitable for sensitive detection of chiral pharmaceuticals in biological samples, but their use will probably increase in the near future. Overall, it seems that one mode of CE-MS, in particular capillary zone electrophoresis (CZE)-MS, is now recognized as established technique for analysis of small charged solutes, but other modes, such as MEKC-MS and CEC-MS, are still within a period of development in terms of both MS-compatible pseudostationary phases and columns as well as applications.

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The advent of the cylindrical internal reflectance (CIRCLE) cell has solved the difficult problem of quantitation of solutes in aqueous solutions by infrared spectroscopy. By a combination of flow injection analysis (FIA) and Fourier transform infrared (FT-IR) spectroscopy with the CIRCLE cell, a fast, reproducible technique suited for the determination of two choline compounds of pharmaceutical interest—succinylcholine chloride and bethanechol chloride—was developed. Quantitation was carried out with the use of either the ester band at 1075 cm−1 for bethanechol or the trimethyl quaternary ammonium band at 953 cm−1 for succinylcholine. Linearity of standard solutions was achieved from about 0.5 to at least 50 ppt for both compounds, and detection limits of 0.02% w/v were possible. A sample throughput of 60 samples/h was estimated. Analysis of pharmaceutical preparations was performed after minor sample clean-up, which was necessary only in the case of the bethanechol chloride tablets.

Descriptions of derivatization reactions applied to high-performance liquid chromatography for pharmaceuticals classified as alkaloids, amines, antibiotics, barbiturates, carbonyl/carboxylic compounds, catecholamines, hydroxy compounds, steroids, sulfur compounds, and miscellaneous are summarized.

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