At-line solid-phase extraction for capillary electrophoresis: application to negatively charged solutes.

Abstract

The analysis of complex biological samples with capillary electrophoresis (CE) requires proper sample pretreatment. In this paper the applicability of solid-phase extraction (SPE) coupled at-line with CE is studied, by using a laboratory-made interface. A fresh (disposable) SPE cartridge is used for each sample to prevent carry-over effects. The sample handling procedure is performed parallel with the analysis of the previous sample, to improve sample throughput. Using this set-up, negatively charged test compounds (some non-steroid anti-inflammatory drugs) can be determined in serum and urine. The method is linear over at least two decades and detection limits are around 40 microg/l. A single capillary, flushed only once a week with a sodium hydroxide solution, was used without problems for the analysis of ca. 900 samples during 1 year. The robustness of the system was very good: no blocking of loop, interface or capillary was found during this period. Furthermore, the system was successfully used for overnight runs.

Cite this paper

@article{Veraart1998AtlineSE, title={At-line solid-phase extraction for capillary electrophoresis: application to negatively charged solutes.}, author={J R Veraart and Cees Gooijer and Henk Lingeman and Nel H Velthorst and U . A . Th . Brinkman}, journal={Journal of chromatography. B, Biomedical sciences and applications}, year={1998}, volume={719 1-2}, pages={199-208} }