Temperature-responsive deep eutectic solvent as eco-friendly and recyclable media for the rapid assessment of pyrethroid pesticide residues in surface soil sample

Abstract

In the modern agricultural model, more and more attention has been paid to green production and sustainable agriculture practices. In this study, a simple and eco-friendly extraction method for the rapid assessment of nine different pyrethroid pesticides in surface soil samples was developed by the temperature-responsive deep eutectic solvent-based ultrasound assisted extraction. Three different temperature-responsive deep eutectic solvent systems of various classes were prepared to extract pyrethroid pesticides from spiked soil samples. The total spiked recovery displayed that temperature-responsive deep eutectic solvent composed of ethanolamine and o-cresol with molar ratio 1:1 was the optimum extraction solvent for temperature-responsive deep eutectic solvent-based ultrasound assisted extraction procedure. Based on Box-Behnken Design, the maximum extraction recovery (%) of total pyrethroid pesticides was 94.23% under the following conditions: extraction temperature of 68 °C, extraction time of 35 min, and solid–liquid ratio of 21 mg/mL. Meaningfully, the extraction recovery of pyrethroid pesticides was still more than 80% after fifth cycles of temperature-responsive deep eutectic solvent, demonstrating that temperature-responsive deep eutectic solvent could be repeatedly used. The detection results of actual soil samples indicated that the pyrethroid pesticide residues (8.42–28.72 μg/kg) in vineyard region were the most serious, which may be due to the high incidence of insect pests and the abuse of pesticides. The temperature-responsive deep eutectic solvent-based ultrasound assisted extraction method with the advantages of fast, trace, and high efficiency could be successfully applied to pyrethroid pesticide residues analysis in surface soil samples.