Ratiometric fluorescent sensing carbendazim in fruits and vegetables via its innate fluorescence coupling with UiO-67

A ratiometric fluorescent sensor was facilely fabricated using innate fluorescence of carbendazim (MBC) and fluorescent UiO-67 to sensitively and selectively detect MBC in food matrixes. The innate fluorescence of MBC provided a signal at 311 nm (F-311), and the fluorescent UiO-67 at 408 nm (F-408) could recognize MBC through pi-pi stacking inducing fluorescent quenching relied on photoelectron transfer (PET). The ratio (F-311/F-408) of the fluorescence enhancement of MBC and the quenching of UiO-67 linearly responded to the MBC concentrations of 0-47.6 mu mol/L with a low limit of detection (LOD) of 3.0 x 10(-3) mu mol/L. The reverse response signals of the sensor enhanced the sensitivity toward MBC and presented remarkable anti-interference capability in complex matrices. The as-prepared sensor was applied to detect MBC residues in apple, cucumber and cabbage, obtaining satisfactory accuracy and precision with the recovery of 90.82-103.45% and RSDs of lower than 3.03%.