Multiclass Determination of 87 Mixed Veterinary Drugs, Pesticides and Mycotoxin Residues in Beef Muscle Samples by Ionic Liquid-Based Dispersive Liquid–Liquid Microextraction and Liquid Chromatography Tandem Mass Spectrometry

A miniaturised, eco-friendly and efficient multiclass method for the simultaneous determination of 87 veterinary drugs, pesticides and mycotoxin residues in beef muscle samples by ionic liquid-based dispersive liquid-liquid microextraction (IL-DLLME) and liquid chromatography tandem mass spectrometry (LC-MS/MS) was developed and validated according to Commission Implementing Regulation (EU) 2021/808 and ISO/IEC 17025: 2017. Under IL-DLLME optimum conditions, matrix calibration yielded a coefficient of determination (<i>R</i>²) ranging from 0.99942 to 0.99997. The limit of detection (LOD) and limit of quantification (LOQ) ranged from 0.93 to 23.78 µg kg^-1 and from 1.98 to 38.27 µg kg^-1, respectively. Recoveries ranged from 80.0 to 109.8% and the decision limit (CCα) values ranged from 13.0 to 523.0 µg kg^-1. Repeatability and reproducibility values were achieved in the ranges of 1.55-12.91% and 1.44-13.35%, respectively. The validated method was applied to 50 real beef samples and 12% of the tested samples contained traces of some residues, but they were all below their respective LOQs and CCα; hence, the beef was fit for human consumption. The greenness of the method was assessed using five green analytical chemistry (GAC) metrics, namely, the Analytical Eco-Scale (AES), NEMI, GAPI, AGREE and ComplexGAPI, and found to be green according to the AES metric and Analytical GREEnness Metric Approach and Software (AGREE). The method provided better results at a greatly reduced cost and analysis time in comparison with standard method.