COUPLED-COLUMN REVERSED-PHASE LIQUID-CHROMATOGRAPHY IN ENVIRONMENTAL-ANALYSIS

An overview is given of the applicability of coupled-column reversed-phase liquid chromatography (LC-LC) to the trace analysis of organic micropollutants in environmental samples, based on typical examples of recent and current work. Although LC-LC, as applied to the analysis of polar pesticides in environmental samples, is usually based on the use of two separation columns with almost similar stationary phase selectivity, it will be shown that a considerable gain in the overall selectivity of methods is attainable. Moreover LC-LC provides sensitivity and potential for automation by utilisation of large volume injections. Due to the large number of parameters involved in the development of analytical procedures a systematic approach towards methodogy is discussed. Two basic types of applications are treated: (i) single-residue methodology focused at the rapid determination of one analyte and (ii) multi-residue methodology for the simultaneous determination of a number of analytes.