Sample preparation for the determination of chlorophenols

Chlorophenols are worldwide toxic contaminants for which a number of official regulatory organizations have set maximum environmental concentrations. Both liquid and gas chromatography combined with a variety of detectors have successfully been used for separation and unambiguous determination of these analytes at trace levels in complex environmental extracts. However, in all instances, pre-concentration and purification of the target compounds have been necessary to achieve adequate detectability. We review the sample-preparation techniques in use for analysis of chlorophenols in relevant environmental, enological and biological samples and highlight recent developments and trends in this field. We use selected examples involving novel analytical approaches for extraction and clean up of these trace pollutants to evaluate the merits of the various techniques on the basis of published data for real-life analysis of biotic and abiotic matrices.CQ thanks Ministerio de Medioambiente for funding via Project A016/2007/3-02.5. LR thanks Ministerio de Educacion (CTQ-2006-14993/BQU) and Ministerio de Medioambiente (A125/2007/3-14.4) for financial support.Peer reviewe