Back‐extraction applied to green matrix solid‐phase dispersion for fungicides determination in tomatoes

Abstract

AbstractMatrix solid‐phase dispersion is an alternate technique to simultaneously extract and clean up pesticides from food matrices. In recent years, deep eutectic solvents have been applied to replace common organic solvents in various extraction techniques. One of the drawbacks of deep eutectic solvents is the impracticality of their evaporation, leading to higher limits of quantification. In this work, a deep eutectic solvent‐based extraction followed by liquid‐liquid back‐extraction was carried out to extract five triazole fungicides from tomato samples followed by high‐performance liquid chromatography‐mass spectrometry analysis. For this purpose, choline chloride‐ethylene glycol in a molar ratio of 1:2 and ethyl acetate was used as a deep eutectic‐organic solvent system. Alumina was used as a dispersant sorbent in a 1‐to‐5 w/w sample‐to‐dispersant ratio. Volumes of 4.5 ml of deep eutectic solvents and 2 ml ethyl acetate were the best choices for back‐extraction. The method was fully validated. The limit of quantification was in the range of 5–11 ng/g. Intra‐day and inter‐day precision ranged between 3% and 14%, respectively. Extraction recoveries varied from 61% to 116%. The matrix effect was also evaluated.