Novel solvent-free microwave-assisted extraction coupled with low-density solvent-based in-tube ultrasound-assisted emulsification microextraction for the fast analysis of organophosphorus pesticides in soils

Abstract

A novel and rapid solventless microwave-assisted extraction coupled with low-density solvent-based in-tube ultrasound-assisted emulsification microextraction has been developed for the efficient determination of nine organophosphorus pesticides in soils by GC analysis with microelectron capture detection. A specially designed, homemade glass tube inbuilt with a scaled capillary tube was used as an extraction device to collect and measure the separated extractant phase easily. Parameters affecting the efficiencies of the developed method were thoroughly investigated. From experimental results, the following conditions were selected for the extraction of organophosphorus pesticides from 1.0 g of soil sample to 5 mL of aqueous solution under 226 W of microwave irradiation for 2.5 min followed by ultrasound-assisted emulsification microextraction with 20 μL toluene for 30 s and then centrifugation at 3200 rpm for 3 min. Detections were linear in the range of 0.25-10 ng/g with detection limits between 0.04 and 0.13 ng/g for all target analytes. The applicability of the method to real samples was assessed on agricultural contaminated soils and the recoveries ranged between 91.4 and 101.3%. Compared to other methods, the present method was shown to be highly competitive in terms of sensitivity, cost, eco-friendly nature, and analysis speed.

Ultrapreconcentration and determination of organophosphorus pesticides in water by solid‐phase extraction combined with dispersive liquid–liquid microextraction and high‐performance liquid chromatography

“…Among various pesticide classes, organophosphorus pesticides (OPPs) exhibit moderate environmental persistence and are one of the most widely used class of agricultural pesticides . Recently, extensive studies have proved OPPs to be reproductively toxic, mutagenic, carcinogenic, cytotoxic, genotoxic, teratogenic and immunotoxic . A simple, rapid and sensitive analytical method to monitor OPP residues has become an important issue due to their high toxicity and potential risk to humans and animals.…”

Ultra-preconcentration and determination of organophosphorus pesticides in soil samples by a combination of ultrasound assisted leaching-solid phase extraction and low-density solvent based dispersive liquid–liquid microextraction

“…12,13 Before analysis, due to the complexity of soil sample matrices, their incompatibility with the desired instrumental method and low concentrations of the analytes in soil, a preliminary sample preconcentration and/or separation technique is required. For the determination of OPPs, the separation and preconcentration methods reported in the literature are usually based on techniques such as supercritical uid extraction, 2,14 microwave-assisted extraction, 4,15 pressurized liquid extraction, 16,17 ultrasonic extraction 18 and solid phase extraction (SPE). 19 Various congurations of microextraction techniques have frequently been reported as alternatives to the classical approaches in the literature.…”

An on-line sample pretreatment technique for the HPLC analysis of plant samples

“…In addition, some other microextraction techniques (e.g. microwave‐assisted extraction coupled with in‐tube ultrasound‐assisted emulsification microextraction , headspace solid‐phase microextraction , headspace sorptive extraction ) can also be used for solid samples, and the automation of these methods is very difficult for solid samples.…”