Comparative Evaluation of Analytical Methods for the Determination of Insecticide Residues in Green Chilli (Capsicum...

This study compares four different analytical methods for residue extraction to establish an efficient and cost-effective sample analysis method for green chilli matrix after spiking. Modified Dutch mini-Luke method, ethyl acetate extraction method and two modified QuEChERS methods with different amounts of sorbent were assessed for the detection of insecticide residue in green chilli fruits using liquid chromatography tandem mass spectrometry (LC-MS/MS). Chilli matrix was spiked with cyantraniliprole, lufenuron, spidoxamat and spinetoram and its metabolites (N-demethyl and N-formyl) at different fortification levels from 0.010 to 0.100 mg/kg (replication [n] = 5) to evaluate the efficiency of the aforementioned analytical method. Modified QuEChERS method with a higher amount of sorbent was found to be the most suitable of all methods (with recovery 91.6%-109.8% [ANOVA; p < 0.001]), whereas the modified QuEChERS with a lower amount of sorbent showed inconsistent results due to matrix interference. The rest of the tested methods were unable to give acceptable recoveries (17.23%-67.00%) (ANOVA; p < 0.001). Among these analytical methods, the modified QuEChERS analytical method was found to be the best suited for the extraction of the aforementioned insecticides and metabolite residues from a problematic complex matrix like green chilli showcasing acceptable method validation guidelines as per SANTE.