Semistable emulsion assisted dispersive liquid–liquid microextraction for the determination of fungicide residues via HPLC

Abstract

Fungicide residues in food can pose serious hazards to humans. The aim of this study was to establish a new method of semistable emulsion assisted dispersive liquid–liquid microextraction (DLLME) for the preconcentration and determination of fungicide residues in juice samples. In this study, Gum Acacia (GA) was selected as the dispersive agent and decanoic acid was adopted as the extractant in aqueous sample. Based on that, a semistable emulsion was induced to facilitate the extraction of target analytes and automatic phase separation. The mechanistic analysis results revealed that the formation of the semistable emulsion was attributed to the mild emulsification of GA with a high molecular weight. Besides, the semistable emulsiont allowed the automatic phase separation in DLLME for the first time. Moreover, the novel method was optimized for detecting fungicide residues and exhibited good linearity (R2 ≥ 0.995), precision (≤16.2 %), matrix effect (≤9.8 %), method recovery (84.0–103.6 %), as well as a low limit of detection (0.5–2.5 μg·L−1) and quantitation (1–5 μg·L−1). In conclusion, this method can be employed to effectively measure fungicide residues in juice samples (orange, grape, carrot and peach). Furthermore, this method can be considered as an effective DLLME alternative for the automatic pretreatment of samples, exhibiting a promising application prospect in food safety.