Ionic‐liquid‐based dispersive liquid–liquid microextraction combined with high‐performance liquid chromatography for the determination of multiclass pesticide residues in water samples

Abstract

Ionic-liquid-based dispersive liquid-liquid microextraction in combination with high-performance liquid chromatography and diode array detection has been proposed for the simultaneous analysis of four multiclass pesticide residues including carbaryl, methidathion, chlorothalonil, and ametryn from water samples. The major experimental parameters including the type and volume of ionic liquid, sample pH, type, and volume of disperser solvent and cooling time were investigated and optimum conditions were established. Under the optimum experimental conditions, limits of detection and quantification of the method were in the range of 0.1-1.8 and 0.4-5.9 μg/L, respectively, with satisfactory enrichment factors ranging from 10-20. The matrix-matched calibration curves, which were constructed for lake water, as a representative matrix were linear over wide range with coefficients of determination of 0.996 or better. Intra- and interday precisions, expressed as relative standard deviations, were in the range of 1.1-9.7 and 3.1-7.8%, respectively. The relative recoveries of the spiked environmental water samples at one concentration level were in the range of 77-102%. The results of the present study revealed that the proposed method is simple, fast, and uses environmentally friendly extraction solvent for the analysis of the target pesticide residues in environmental water samples.

Extending the scope of dispersive liquid–liquid microextraction for trace analysis of 3-methyl-1,2,3-butanetricarboxylic acid in atmospheric aerosols leading to the discovery of iron(III) complexes

“…The obtained limit of detection of MBTCA (0.12 pg/m 3 ) is significantly lower than the limits of detection reported by, e.g., Fu et al [6], Zuth et al [31], Ding et al [19], and Kourtchev et al [2] that were 0.005, 1.3, 2, and 4 ng/m 3 respectively. Tadesse et al [12] reported enrichment factors of 10.2–19.6 for DLLME of multiclass pesticide residues in water samples. Additive-assisted DLLME for extraction of polar compounds such as MBTCA provided an enrichment factor of 16.6 that is fairly comparable to earlier DLLME studies of non-polar compounds.…”

“…Dispersive liquid–liquid microextraction (DLLME) has gained popularity owing to its simplicity, low cost, enrichment of analyte, and short extraction times [ 8 – 12 ]. However, traditional sample preconcentration techniques like solid-phase extraction have been used for the extraction of polar compounds from aerosols [ 13 ].…”