Development of simultaneous analytical method for the determination of fluazaindolizine and its seven metabolites in agricultural products by liquid chromatography tandem mass spectrometry

A simultaneous analytical method has been developed for quantification and confirmation of the nematicide fluazaindolizine and its seven metabolites (IN-A5760, IN-F4106, IN-QEK31, IN-QZY47, IN-TMQ01, IN-UNS90 and IN-UJV12) in agricultural products. The compounds were extracted with acetonitrile/water (80/20, v/v) and purified using C18 cartridge, and analysis was conducted by liquid chromatography-tandem mass spectrometry in the electrospray positive and negative ion mode. The method has been validated by verifying the performance characteristics such as selectivity, linearity, limit of detection (LOD), limit of quantification (LOQ), accuracy and precision. To prevent the matrix effects, all analytes were quantified with matrix-matched calibration assessed by the determination coefficient (R2) of the range from 0.9988 to 1.0000. The LOD and LOQ were satisfactory to determine the low residual level in agricultural products. The accuracy and precision of the method were evaluated by recoveries with five replicates at three fortification levels (LOQ, 10 × LOQ and 50 × LOQ). The mean recoveries of fluazaindolizine and seven metabolites in agricultural products were 75.6–110.0% with the CV% of 0.2–9.1%. All optimized results were displayed excellent results assessed by the Ministry of Food and Drug Safety guidelines and the Codex Alimentarius Commission guidelines for pesticide residue analysis. This study could use as basic data for setting of residue definition and maximum residue limits of fluazaindolizine in agricultural products.