Solid-phase microextraction coupled with high performance liquid chromatography: a complementary technique to solid-phase microextraction-gas chromatography for the analysis of pesticide residues in strawberries

Abstract

Solid-phase microextraction coupled with high performance liquid chromatography has been studied for the analysis of methiocarb, napropamide, fenoxycarb and bupirimate in strawberries. The strawberries were blended and centrifuged. Then, an aliquot of the resulting extracting solution was subjected to solid-phase microextraction (SPME) on a 60 microns polydimethylsiloxane/divinylbenzene (PDMS/DVB) fibre for 45 min at room temperature. The extracted pesticides on the SPME fibre were desorbed into SPME/high performance liquid chromatography (HPLC) interface for HPLC analysis with diode-array detection (DAD). The method is organic solvent-free for the whole extraction process and is simple and easy to manipulate. The detection limits were shown to be at low microgram kg-1 level and the linear response covered the range from 0.05 to 2 mg kg-1 of pesticides in strawberries with a regression coefficient larger than 0.99. A good repeatability with RSDs between 2.92 and 9.25% was obtained, depending on compounds.

Application of solid-phase microextraction for the determination of pyrethroid residues in vegetable samples by GC-MS

“…This approach has already been applied by other authors for SPME extraction in different solid samples such as soils or fruits [33,45]. Extraction of the samples was first performed by mixing 0.5 g of chopped spiked tomato with 2.5 mL of distilled water and 0.5 g of NaCl, and the mixture was submitted to an ultrasonic shaking for 30 min.…”

“…Although several papers deal with direct immersion of the SPME fiber into a slurry of fruit with water [21,29], other authors describe the need for a previous extraction of pesticides and the subsequent application of DI-SPME over the separated aqueous extract [30,31,32,33]. The use of microwave-assisted extraction allows one to increase the extraction efficiency of less polar pesticides using water as extractant [29,34].…”

Coupling solid-phase microextraction to liquid chromatography. A review

“…Two methods for SPME-HPLC-UV-DAD determination of pesticide residues in strawberries have been developed by the same research group [61,62]. In the first strawberries were first blended with water and the mixture was centrifuged before SPME; the second proposes the use of focused microwave-assisted extraction before SPME to reduce the strong matrix effect observed in blended samples.…”

Determination of Diphenamide, Napropamide and Metolachlor in Tobacco by Gel Permeation Chromatographic Clean-Up and High Performance Liquid Chromatography

“…[1][2][3] For food and environment safety, the detailed investigations on their residues and metabolism are very important. Diphenamide, napropamide and metolachlor in the pesticide products, serum, urine, soil, environmental water, fruits and wine have been widely analyzed by ELISA, 4-7 fluorescence, 8 phosphorescence, 9 capillary electrophoresis, 10 high performance liquid chromatography (HPLC), [11][12][13][14][15] gas chromatography(GC) and GC mass spectrometry (GC-MS). [16][17][18] However, to our knowledge, simultaneous residue analysis of diphenamide, napropamide and metolachlor in tobacco samples has not been extensively documented.…”