Determination of Pesticide Residues in Soy-Based Beverages Using a QuEChERS Method (with Clean-Up Optimized by Central Composite Design) and Ultra-High-Performance Liquid Chromatography-Tandem Mass Spectrometry

Soybean production is responsible for a great amount of pesticides applied in Brazil. In the last years, an increase of soy-based beverage consumption and a higher concern about pesticide residues in food occurred. A simple, fast, and efficient multiresidue method based on the quick, easy, cheap, effective, rugged, and safe (QuEChERS) method was developed for simultaneous determination of 39 pesticides and two plant growth regulators in soy-based beverages by ultra-high-performance liquid chromatography-tandem mass spectrometry (UHPLC-MS/MS). The clean-up procedure was established based on central composite design (CCD), using response surface methodology (RSM). For the optimization of the clean-up step, different amounts of sorbents in dispersive solid phase extraction (d-SPE) were evaluated. Validation results were satisfactory, considering that the optimized method presented recoveries between 70 and 112 %, with RSD lower than 19 % for spike levels between 10 and 50 μg L^?1. The method limit of detection (LOD) and quantification (LOQ) ranged from 3 to 8 and 10 to 25 μg L^?1, respectively. The proposed method combines the advantages of QuEChERS and UHPLC-MS/MS and proved to be suitable for the pesticide multiresidue determination in soy-based beverages in routine laboratory analyses.