Development of boronic-acid-functionalized magnetic metal organic framework coupled with ambient ionization mass spectrometry for the analysis of neonicotinoid insecticides in fruits and vegetables.

Abstract

A novel magnetic dispersive solid phase extraction (MDSPE) based on boronic acid-functionalized magnetic metal organic framework (Fe3O4@UiO-66(Zr)-BA) coupled with pulsed direct current electrospray ionization (PDESI), an ambient ionization mass spectrometry (AMS), was developed for the determination of muti-generation neonicotinoid insecticides (NIs) in fruits and vegetables. The synthesized Fe3O4@UiO-66(Zr)-BA efficiently extracted of NIs via synergistic interactions, and the adsorption mechanism was investigated. Compared to conventional laboratory methods, this approach enhanced analytical efficiency by integrating magnetic separation and eliminating chromatographic separation. The established method achieved low limits of detection (LODs) of 0.9-2.9 ng/g, with relatively standard deviations (RSDs) below 14.8 %, and correlation coefficients (r > 0.99) were achieved. Successful application to fresh cowpeas, cucumbers, and apples confirmed its practicality, with risk assessment indicating minimal human health risks from NIs exposure. This work provides an effective and practical analytical strategy for the routine monitoring and risk assessment of NIs in agricultural products.