Application of dynamic liquid-phase microextraction to the analysis of chlorobenzenes in water by using a conventional microsyringe.

A dynamic liquid-phase microextraction technique combined with gas chromatography/mass spectrometry (GC/MS) is described for the extraction of 10 chlorobenzenes from water samples into 1 microL of organic solvent by using a conventional microsyringe. The effects of extraction solvent, plunger movement pattern, sampling volume, number of samplings, and salt concentration on the extraction performance were investigated. Good repeatabilities of extraction were obtained, with the RSD values below 5.3% except for hexachlorobenzene (9.3%). By using a sampling volume of 6 microL and 15 samplings, detection limits were found to be between 0.02 and 0.05 microgram/L under GC/MS-selective ion monitoring mode.