Determination of amide herbicides in food by salting-out vortex-assisted dispersive liquid–liquid microextraction coupled with gas chromatography-tandem mass spectrometry

Abstract

A new method, salting-out vortex-assisted dispersive liquid–liquid microextraction (SO-VA-DLLME), was developed for extracting amide herbicides (AHs) from food samples. Quantitative analysis of AHs was performed using gas chromatography-tandem mass spectrometry (GC-MS/MS). One-variable-at-a-time testing was used to investigate the impact of the experimental parameters on extraction efficiency. Based on the results of our previous research, this study analyzed the impact of various extraction factors on AH extraction efficiency and improved pre-treatment conditions using response surface methodology (RSM) and a back propagation-genetic algorithm (BP-GA) neural network model. Specifically, the BP-GA neural network exhibited exceptional stability during AH extraction, facilitating comprehensive optimization. The method demonstrated excellent linearity (R² ≥ 0.992) within the 2.00–2000 ng kg⁻¹ range. The detection limits (LODs) were estimated to be 0.060–1.20 ng kg⁻¹, and quantitation limits (LOQs) were 0.200–2.00 ng kg⁻¹ at S/N ratios of 3 and 10, respectively. Extraction recoveries ranged from 87% to 98%, with enrichment factors of 3480 to 3920, indicating effectiveness. Intra-day and inter-day relative standard deviations (RSDs) were below 9.60%, ensuring reliability. In line with the white analytical chemistry principles, the method confirmed environmental safety. Overall, this rapid, cost-effective method efficiently detected amide herbicides in food samples.