Analysis of phenylurea and propanil herbicides by solid-phase microextraction and liquid chromatography combined with post-column photochemically induced fluorimetry derivatization and fluorescence detection

This study examines the application of solid-phase microextraction coupled with high performance liquid chromatography combined with ost-column photochemically induced fluorimetry derivatization and fluorescence detection (SPME–HPLC–PIF–FD) for the determination of four henylurea herbicides (monolinuron, diuron, linuron and neburon) and propanil in groundwater. Direct immersion (DI) SPME was applied using 60 m polydimethylsiloxane/divinylbenzene (PDMS/DVB) fiber for the extraction of the pesticides from groundwater samples. An AQUASIL 18 column (150 mm× 4.6 mm i.d., 5 m) was used for separation and determination in HPLC. The method was evaluated with respect to the imits of detection (LODs) and the limits of quantification (LOQs) according to IUPAC. The limits of detection varied between 0.019 g L−1 and .034 g L−1. Limits of quantification ranged between 0.051 g L−1 and 0.088 g L−1. These values meet the recommended limits for individual esticides in groundwater (0.1 g L−1) established by the EU. Recoveries ranged between 86% and 105% and relative standard deviation values etween 2% and 8%. 2007 Elsevier B.V. All rights reserved.