Determination of 2,4‐dichlorophenoxyacetic acid in environmental and food samples using salt‐assisted liquid‐liquid extraction coupled with micro‐channel and high‐performance liquid chromatography

Abstract In this research, 2,4‐dichlorophenoxyacetic was determined using a salt‐assisted liquid‐liquid extraction in a micro‐channel. Firstly, the sample solution, extraction solvent, and salt were mixed with a magnet stirrer, and then the mixture was transferred into a micro‐channel using a syringe pump. Affecting factors on the extraction efficiency of 2,4‐dichlorophenoxyacetic such as extraction solvent and its volume, salt amount, pH of sample solution, micro‐channel shape, length, and inside diameter were investigated and optimized. Under the optimized conditions, the detection limit of the proposed method was 0.05 μg/mL, and its linear was in the range of 0.15–30.0 μg/mL with an R 2 coefficient of 0.9927. To show the micro‐channel effect on the efficiency of the proposed method, its extraction efficiency was compared with the conventional salt‐assisted liquid‐liquid extraction method. The results confirm the synergetic effect of micro‐channel on the extraction efficiency of 2,4‐dichlorophenoxyacetic. Finally, the proposed method was successfully applied to determine 2,4‐dichlorophenoxyacetic in environmental and vegetable samples.