Application of ultrasound-assisted emulsification microextraction followed by gas chromatography for determination of organophosphorus pesticides in water and soil samples

Abstract

In the present study a fast, simple and efficient method for determination of organophosphorus pesticides (OPPs) in water and soil samples was developed by using ultrasound assisted emulsification microextraction (USAEME) based on applying low density organic solvents. Fourteen microlitres of toluene was injected slowly into a 12 mL home-designed centrifuge glass vial containing an aqueous sample that was located inside the ultrasonic water bath. The formed emulsion was centrifuged and 2 mL of separated toluene (about 4 mL) was injected into a gas chromatographic instrument equipped with a flame ionization detector for analysis. Under the optimum conditions, preconcentration factors of 2390 and 1390 were obtained for diazinon and chlorpyrifos respectively. The method performance was studied in terms of linear dynamic range (LDRs from 0.01 mg L À1 to 100 mg L À1 ), linearity (r 2 $ 0.9984), precision (repeatability # 8.7%), and extraction percentage (79.9 and 46.3%). Also, limits of detections of 0.01 and 0.1 mg L À1 were obtained for diazinon and chlorpyrifos respectively. The applicability of the USAEME method was evaluated by the extraction and determination of OPPs from some natural water and soil samples.

SPME determination of low concentration levels of monoaromatic chemical markers in soils after remediation by supercritical fluid extraction

“…[1][2][3][4][5][6] The latter are oen indicators of contamination by compounds derived from petroleum, such as gasoline, which are frequently found in soils near gas stations or oil reneries. PAHs (polycyclic aromatic hydrocarbons), PCBs (polychlorinated biphenyls), pesticides, pharmaceuticals and monoaromatic hydrocarbons (benzene, toluene, ethylbenzene and three isomers of xylene) are frequently found in soil.…”

Development of a dispersive liquid–liquid microextraction method with a new sequence of steps and its comparison with a conventional method

“…Also, these compounds contaminate surface water, soil, etc. . So, it is necessary to develop simple, rapid, and sensitive analytical methods for determination of trace OPP residues in foods and environmental samples.…”

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

“…For the determination of OPPs, the separation and preconcentration methods reported in the literature are usually based on supercritical fluid extraction, 2,14 microwave-assisted extraction, 4,15 pressurized liquid extraction, 16,17 ultrasonic extraction 18 and solid phase extraction (SPE), 19 etc. Solid phase microextraction 20 and liquid phase microextraction 7,21 are fairly new methods of sample preparation for the preconcentration of OPPs, and have been proved to be simple, inexpensive, fast and virtually solvent-free sample pretreatment techniques with extensive application. Solid phase microextraction 20 and liquid phase microextraction 7,21 are fairly new methods of sample preparation for the preconcentration of OPPs, and have been proved to be simple, inexpensive, fast and virtually solvent-free sample pretreatment techniques with extensive application.…”