Application of SPE‐HPLC‐DAD and SPE‐TLC‐DAD to the determination of pesticides in real water samples

Abstract

Planar chromatography with diode array scanning (TLC-DAD) and high-performance chromatography with diode array detection (HPLC-DAD) were used to screen water samples for pesticides. Pesticides were enriched from lake water samples by SPE on C18/SDB-1, C18, C18 Polar Plus and cyanopropyl (CN) cartridges. The recovery rates were high for all extraction materials except for all pesticides on CN cartridges, for which the values were lower. SPE was used not only for preconcentration of analytes but also for their fractionation. The analytes were eluted first with methanol and then with dichloromethane. Methanol eluates were analysed by HPLC-DAD, the dichloromethane eluates with TLC-DAD. The method was validated for precision, repeatability and accuracy. The calibration plots were linear between 0.1 and 50.0 microg/mL for all pesticides, the correlation coefficients, r, were between 0.9992 and 1.000 as determined by HPLC-DAD. In the TLC experiments, the best fit for the calibration lines was found when the calibration data were analysed using a second-degree polynomial regression. Calibration plots lay between 0.1 and 17 microg/spot for all pesticides, the correlation coefficients, r, were between 0.9974 and 0.9997 determined by TLC-DAD. The LOD was between 0.04 and 0.65 microg/spot (TLC-DAD) and between 0.02 and 3.68 microg/mL (HPLC-DAD).

Dispersive micro-solid phase extraction based on self-assembling, ionic liquid-coated magnetic particles for the determination of clofentezine and chlorfenapyr in environmental water samples

“…A suitable extraction method for the determination of pesticides at trace levels in environmental samples is required. Techniques, such as solid phase extraction (SPE) 11,12 and solid phase microextraction (SPME), 13,14 have been developed for the separation and the preconcentration of analytes from different matrices. The coating of materials on SPME bers is generally limited, which is disadvantageous for extraction efficiency.…”

Basic Principles of Planar Chromatography and Its Potential for Hyphenated Techniques

“…The limit of detection (LOD) was between 0.04 and 0.23 mg/spot (TLC-DAD) and between 0.02 and 0.45 mg ml À1 (HPLC-DAD) (Tuzimski 2008a). Application of SPE and HPLC-DAD and/or TLC-DAD to the determination of pesticides in water samples from lakes from Łęczyńsko-Włodawskie Lake District (South-Eastern Poland) was also described (Tuzimski 2008b(Tuzimski , 2009aTuzimski and Sobczyński 2009). Dichloromethane eluates were analyzed by TLC-DAD (Fig.…”

Synthesis of magnetic multiwall carbon nanotubes for enantioseparation of three pesticide residues in fruits and vegetables by chiral liquid chromatography

“…For the pesticides in fruits and vegetables, it is challenging to develop an effective method to extract and analyze since they occur in complex matrixes at trace levels. A number of methods have been used to deal with complex matrixes such as: solid phase extraction (SPE), matrix solid‐phase dispersion (MSPD), quick, easy, cheap, effective, rugged, and safe (QuEChERS) method, and ultrasound‐assisted solvent extraction …”

“…For the pesticides in fruits and vegetables, it is challenging to develop an effective method to extract and analyze since they occur in complex matrixes at trace levels. A number of methods have been used to deal with complex matrixes such as: solid phase extraction (SPE), [3][4][5] matrix solid-phase dispersion (MSPD), [6][7][8] quick, easy, cheap, effective, rugged, and safe (QuEChERS) method, 1,9,10 and ultrasound-assisted solvent extraction. [11][12][13] The SPE technology is one of the most frequently used approaches for cleanup of pollutants, owing to the advantages such as high enrichment factor and low organic solvent consumption.…”