Abstract: A novel double-windows fluorescent sensor for carbofuran (CF) detection was successfully developed based on rare-earth Eu, Tb-doped Y2O3@SiO2-based molecularly imprinted nanoparticles (MINs) with multilayer core-shell structure. The recognition process of the MINs for CF was fairly fast and merely need ca. 8 min to reach a dynamic equilibrium. Interestingly, one fluorescent attenuation window was found with an increase of CF concentration (Q) from 0.1 to 10 μg mL-1 with the limit of detection (LOD) of 0.04 μg mL-1 at 544 nm belonging to the Tb3+ emission, as well as the other fluorescence enhanced window within the range of CF concentration from 10 to 100 μg mL-1 (LOD = 4 μg mL-1) at 617 nm of Eu3+ emission in the dispersed rare-earth doped MINs colloidal aqueous solution. Simultaneously, it was obviously observed that the luminescent resonance energy transfer from CF to Eu3+, and an inner filter effect of CF towards Tb3+ as well from the two independent detection windows. The competition experiment displayed hardly any remarkable interference during the detection of CF by addition of its analogues (carbaryl, isoprocarb, aldicarb, methomyl and etofenprox). Moreover, the MINs could also be applied to accurately detect CF in the rhubarb and wolfberry samples with the recoveries of 85.7%-92.2%. The sensing system has high specific recognition and wide detection range to CF and provides new opportunities in pesticide detection
Author keywords: Double windows, Rare earth, Fluorescent molecularly imprinted sensor, Carbofuran