Simultaneous quantification of Two Neonicotinoids using QuERChERS-LC-MS/MS in Moroccan Spearmint (Mentha Spicata.L): Qualimetry of the method by Uncertainty estimation using Generalized Pivotal Quantities approach and Monte Carlo simulation

Abstract

Background Neonicotinoids are used for the phystosanitary treatment of Mentha Spicata.L crops, and this practice requires precise control of these harmful substances at very low concentrations. Objective The objective of this study is to apply an approach allowing simultaneously validation and evaluation of measurement uncertainty based on total error methodology, in order to accurately quantify the presence of two neonicotinoids in Mentha Spicata.L utilizing a QuEChERS-LC-MS/MS methodology. Methods Assay of Imidacloprid and Acetamiprid using QuEChERS extraction method coupled with LC-MS/MS to guarantee the analytical method's accuracy and control the risk of its routine use. A complete and exhaustive validation approach based on the “β-content, γ-confidence” tolerance interval was used for the uncertainty assessment, using the Generalised Pivot Quantity (GPQ) concept and Monte Carlo simulation, which avoids the need for additional data while achieving intermediate precision for each concentration level within predetermined acceptable limits. Results The validation procedure is based on the choice of a quadratic model for the two neonicotinoids, allowing the validation of Acetamiprid and Imidacloprid by LC-MS/MS assay within the range of working concentration. The flexibility of the Uncertainty Profile intervals was demonstrated with a variation in β-content values (66.7%, 80%, and 90%) and risk values (10% and 5%), which remained within the acceptability limits of 20%, and the relative expanded uncertainty did not exceed 15% and 11%. Conclusion QuEChERS- LC-MS/MS method for the analysis of two neonicotinoids has successfully been fully validated using the Uncertainty Profile strategy. Highlights Application of a full validation strategy based on the validation and uncertainty assessment for the quantification of two main Neonicotinoids in Mentha Spicata.L using QuEChERS- LC-MS/MS. This qualimetric has been conducted by computing of the measurement uncertainty of the method utilizing data from analytical validation under conditions of intermediate precision at each level of concentration without additional effort, after that we have demonstrate the flexibility of this strategy for the LC-MS/MS quantification of acetamiprid and imidacloprid, using a decision tool that enables the choice and modification of β-content and γ-confidence values.