DETERMINATION OF FLONICAMID IN TOMATOES AND TOMATO JUICE BY THE METHOD OF HIGH-PERFORMANCE LIQUID CHROMATOGRAPHY WITH MASS SPECTROMETRY DETECTION

Abstract

Introduction. Flonicamid is a new systemic insecticide with selective action from the class of pyridinecarboxamides, the control of residual amounts of which, according to the current requirements of the European Commission, should be carried out taking into account its two metabolites. The aim of the study is development of a method for the determination of flonicamid (sum of flonicamid and its metabolites TFNA and TFNG expressed as flonicamid) for the control of established medical and sanitary standards in tomatoes and tomato juice. Research Methods. Chromatographic analysis was performed on a Shimadzu Nexera X2 liquid chromatograph with a Shimadzu LCMS-8050 three-quadrupole mass spectrometric detector using chromatographic steel columns RaptorTM Biphenyl 2.7 μm 100 × 2.1 mm and Kinetex® 2.6 μm C18 100 Å 100 × 2.1 mm. Tomato and tomato juice samples were prepared based on the QuEChERS methodology. Results and Discussion. The results obtained using different mobile phases, elution options and sample introduction modes on the studied columns demonstrated the superiority of the Kinetex® 2.6 μm C18 100 Å 100 × 2.1 mm column for the analysis of flonicamid and its metabolites TFNA and TFNG under mobile phase gradient elution (eluent A – 0.1 % aqueous solution of formic acid; eluent B – 0.1 % solution of formic acid in acetonitrile) and co-injection mode. Selected MRM transitions: flonicamid – (ESI+) 230 > 203, 230 > 148; TFNG – (ESI+) 249 > 203, 249 > 148; TFNA – (ESI+) 192 > 148, 192 > 98. The optimal conditions of chromatography and mass spectrometric detection made it possible to determine flonicamid and its metabolites TFNA and TFNG in samples of tomatoes and tomato juice prepared according to the QuEChERS methodology with a limit of quantification (for each compound) of 0.01 mg/kg. Conclusions. The method for determining flonicamid (sum of flonicamid, TFNA and TFNG expressed as flonicamid) in tomatoes and tomato juice with a limit of quantification of 0.03 mg/kg (in each matrix) ensures control of established medical and sanitary regulations standards in accordance with international requirements and norms.