Phenolic-based non-ionic deep eutectic solvent for rapid determination of water soluble neonicotinoid insecticides in
Huiyu Zhao1, Ze Wang1, Cong Zhang2
1State Key Laboratory for Managing Biotic and Chemical Threats to the Quality and Safety of Agro-products/ Key Laboratory of Detection for Pesticide Residues and Control of Zhejiang, Institute of Agro-product Safety and Nutrition, Zhejiang Academy of Agricultural Sciences, Hangzhou 310021, China.
Abstract:
Challenges were raised to established analytical method for monitoring water soluble neonicotinoid insecticide (NEOs) residues in tea infusion. Phenolic-based non-ionic deep eutectic solvent (NIDES) composed by a mixture of DL-menthol and thymol (molar ratio of 1:3) was applied to achieve the determination of selected NEOs. Factors influenced extraction efficiency have been evaluated and molecular dynamics approach was conducted aming to provide a new insight to explain its extraction mechanism. It is found that Boltzmann averaged solvation energy of NEOs was negatively correlated with extraction efficiency. The method validation results indicated good linearities (R2 ≥ 0.99), sensitive LOQs (0.05 μg L-1), high precisions (RSD < 11%) and satisfactory recoveries (57.7%∼98%) at 0.05 μg L-1 ∼ 100 μg L-1. The intake risk of NEOs in tea infusion samples were acceptable which residues in range of 0.1 μg L-1 ∼ 3.5 μg L-1 for thiamethoxam imidacloprid and thiacloprid. This method showed advantages of rapid, green, and easy operation.
