Development and validation of UHPLC-MS/MS methods for determination of neonicotinoid insecticides in royal jelly-based products

In this study, new methods have been proposed to determine seven neonicotinoid insecticides (dinotefuran, nitenpyram, thiamethoxam, clothianidin, imidacloprid, acetamiprid and thiacloprid) in royal jelly-based products, by means of ultra-high-performance liquid chromatography coupled to a quadrupole-time-of-flight mass detector. Efficient sample treatments (with average analyte recoveries between 83% and 109%) involving solid-phase extraction (polymeric sorbent, Strata® X) and a dispersive liquid-liquid microextraction, were proposed to determine these neonicotinoids in liquid dietary supplements containing freeze-dried royal jelly and fresh royal jelly, respectively. Chromatographic analysis (8 min) was performed on a core-shell technology-based column (Kinetex® EVO C18). Both methods were fully validated and the data demonstrated that they are consistent, reliable and have a wide linear range of applicability. Low limits of quantification, ranging from 2.5 to 9.5 μg/kg, were obtained in all cases, and it was necessary to employ matrix-matched standards for correct quantification of three of the compounds in each of the royal jelly-based products. Finally, the proposed methods were applied to neonicotinoid analysis of royal jelly-based products from different Spanish regions.