Potential of short-column liquid chromatography with tandem mass spectrometric detection for the rapid study of pesticide degradation

The applicability of solid-phase extraction-LC using two short columns (SPE -LC) and/or single-short-column liquid chromatography (SSC) combined on-lin e with tandem mass spectrometry (MS) was demonstrated for the rapid study o f pesticide degradation. A fast analytical procedure was developed to provi de preliminary information concerning experimental conditions, approximate rates of degradation and identity of the degradation products. Surface wate r samples were spiked at relevant concentration levels with well-known micr o-contaminants and photolysis was used to transform parent compounds into t heir degradation products. In general, the strategy was as follows: at 30-m in intervals 10-mL samples were on-line enriched, separated by short-column LC and recorded in full-scan MS to obtain information on the disappearance of the parent compound and the appearance of breakdown products. To obtain structural information, product-ion spectra of selected compounds appearin g in the full-scan MS chromatogram were recorded; this enabled the identifi cation of several degradation products. Total analysis time of enrichment/s eparation and detection was about 10-15 min.