Microfunnel‐filter‐based emulsification microextraction followed by gas chromatography for simple determination of organophosphorus pesticides in environmental water samples

Abstract

A simple and fast method named microfunnel-filter-based emulsification microextraction is introduced for an efficient determination of some organophosphorus pesticides including diazinon, malathion, and chlorpyrifos in the environmental samples including the river, sea, and well water. This method is based upon the dispersion of a low-toxicity organic solvent (dihexyl ether), as the extractant, in a high volume of an aqueous sample solution (45 mL). It is implemented without a centrifugation step, and using a syringe filter and a micro-funnel, the phase separation and transfer of the enriched analytes to the gas chromatograph are simply achieved. By filtration of the extractant phase, a suitable sample clean-up is obtained, and the total extraction time is just a few minutes. The factors influencing the extraction efficiency are optimized, and under the optimal conditions, the proposed method provides a good linearity (in the range of 15-1500 ng/mL (R 2 > 0.996). A high enrichment factor is obtained (in the range of 306-342), and the method provides low limits of detection and quantification (in the ranges of 4-8 and 15-25 ng/mL, respectively). K E Y W O R D Scentrifugeless method, environmental water samples, microextraction, microfunnel-filtration-based method, organophosphorus pesticides 2418

What are the Main Sensor Methods for Quantifying Pesticides in Agricultural Activities? A Review

“…In a more specific water sample, taken from rivers, we obtained, as minimum values of the limits of quantification, 3.5 × 10 −14 μg/mL and 2.06 × 10 −9 μg/mL for the biosensor based on QCM [77] and an AChE/AuNPs/VNSWCNTs biosensor [107]. Meanwhile, the quantification limits for gas chromatography methods correspond to 6.00 × 10 −3 μg/mL [42].…”

“…The first two values are based on a gold nanoparticle/three-dimensional graphene film (AuNPs/rGO) [116], and the second pair of values is based on AuNPs, with a VNSWCNTs overlay [107]. All detections show quite low limits in contrast to a classical method, based on the micro-extraction of emulsion using a micro funnel filter, followed by CG [42] (8.00 × 10 −3 μg/mL, for MTH, and 1.30 × 10 −4 μg/mL for the MPHT method based on HPLC-DAD [23]).…”

“…It was found that for diazinon (DZ) the lowest LOD was 5.00 × 10 −4 μg/mL using an AChE biosensor based on the modulated fluorescence [121] of UCNPs-Cu 2+ , in contrast to the method of MFEM-MS [42], which registered a value of 4.00 × 10 −03 μg/mL. In the case of the herbicide DU, 6.99 × 10 −6 μg/mL was the lowest value of LOD, obtained by means of the square wave voltammetry technique [52], whereas by the DPX-HPLC/DAD method [23], a value of 6.00 × 10 −5 μg/mL was obtained, this being the only case where a similar LOD value was obtained for the aqueous matrices.…”

Analytical methods to analyze pesticides and herbicides

“…Talaee, Lorestani, Ramezani, Cheraghi, and Jamehbozorgi (2019) used microfunnel‐filter‐based emulsification microextraction coupled with GC to determine organophosphorus pesticides (OPs). This method was implemented with a syringe filter and a microfunnel, using dihexyl ether as the extractant, to achieve simple phase separation.…”

Determination of diazinon in water and food samples using magnetic solid‐phase extraction coupled with liquid chromatography

“…Cleanup and preconcentration processes for trace analysis, due to the complexity of matrix and low amount of analyte, are essential. Various sample preparation techniques such as solid-phase extraction (SPE) and micro-solidphase extraction (µ-SPE) [20][21][22], liquid-liquid extraction (LLE), and liquid-liquid microextraction (LLME) [23][24][25][26], magnetic solid-phase extraction followed by dispersive liquid-liquid microextraction (DLLME) [27], matrix solidphase dispersion (MSPD) [28], pressurized liquid extraction (PLE) [29], and electrochemical methods were reported for the determination of diazinon in different matrices [30,31]. SPE is an effective technique for the selective isolation and concentration of a wide range of analytes and sample matrices.…”