Method Validation for Estimation of Imidacloprid and its Metabolites in Maize and Soil by LCMS-MS

Validation of Quick, Easy, Cheap, Effective, Rugged, and Safe (QuEChERS) method was performed for estimation of imidacloprid (IM) and its metabolites in maize leaves, immature kernels, mature kernels, stalk, and soil using liquid chromatograph tandem mass spectrometry, coupled with electrospray ionization. The extraction in different matrices of maize and soil was performed using acetonitrile +0.1% formic acid followed by clean-up with primary secondary amine sorbent and anhydrous magnesium sulfate. The method was validated in terms of selectivity, linearity, limit of detection, limit of quantification, matrix effect, ion ratios, quality control, robustness, accuracy, and precision. The validation of all parameters was done in accordance with European Commission's Directorate-General for Health and Food Safety (DG SANTE) guidelines. A linear relationship with high correlation coefficients R2 > 0.99 was obtained for solvents and different matrices viz., maize leaves, immature kernels, mature kernels, stalk, and soil. The recovery and relative standard deviations were ˃78% and ˂5.4%, respectively. This method permits a simple, sensitive, accurate, cost-effective, precise, and rapid extraction of IM and its metabolites from maize leaves, immature kernels, mature kernels, stalks, and soil. This can help the residue analysts to address effective residue estimation, regular monitoring of residues and can also aid in the regulatory and food safety concerns about the usage of IM in maize.