Determination of chlorophenols by solid-phase microextraction and liquid chromatography with electrochemical detection

A solid-phase microextraction method has been developed for the determination of 19 chlorophenols (CPs) in environmental samples. The analytical procedure involves direct sampling of CPs from water using solid-phase microextraction (SPME) and determination by liquid chromatography with electrochemical detection (LC–ED). Three kinds of fibre [50 μm carbowax-templated resin (CW-TPR), 60 μm polydimethylsiloxane–divinylbenzene (PDMS–DVB) and 85 μm polyacrylate (PA)] were evaluated for the analysis of CPs. Of these fibres, CW-TPR is the most suitable for the determination of CPs in water. Optimal conditions for both desorption and absorption SPME processes, such as composition of the desorption solvent (water–acetonitrile–methanol, 20:30:50) and desorption time (5 min), extraction time (50 min) and temperature (40 °C) as well as pH (3.5) and ionic strength (6 g NaCl) were established. The precision of the SPME–LC–ED method gave relative standard deviations (RSDs) of between 4 and 11%. The method was linear over three to four orders of magnitude and the detection limits, from 3 to 8 ng l−1, were lower than the European Community legislation limits for drinking water. The method was applied to the analysis of CPs in drinking water and wood samples.