Headspace-single drop microextraction with a commercial capillary electrophoresis instrument.

Automated coupling of headspace-single drop microextraction (HS-SDME) and CE has been demonstrated using a commercial CE instrument. When a drop hanging at the inlet tip of a capillary for CE is used as the acceptor phase, HS-SDME becomes a simple but powerful sample pretreatment technique for CE before injection to facilitate sample cleanup and enrichment. By combining HS-SDME with an on-line sample preconcentration technique, large volume sample stacking using an electroosmotic flow pump, the sensitivity can be improved further. The overall enrichment factors for phenolic compounds were from 1900 to 3400. HS-SDME large volume sample stacking using an electroosmotic flow pump was successfully applied to a red wine sample to obtain an LOD of 4 nM (0.8 ppb) for 2,4,6-trichlorophenol which is a precursor for 2,4,6-trichloroanisole causing the foul odor in wine called cork taint.