Sensitive Fluorescence Detection Method for Dinotefuran Using Carbon Quantum Dots as Probe Derived From Glucose and...

Carbon quantum dots (CQDs) were successfully synthesized using glucose and diethylenetriamine as precursors through a one-pot method, achieving a fluorescence quantum yield (QY) of 26.99%. The morphology, structure, and optical properties of the CQDs were characterized using advanced microanalysis including transmission electron microscopy (TEM), ultraviolet visible (UV-vis), fluorescence spectra, Fourier transform infrared (FT-IR), X-ray diffraction (XRD), Raman spectroscopy, thermogravimetric analysis (TGA), X-ray photoelectron spectroscopy (XPS), and zeta potential. The effective binding of dinotefuran (DNF) and CQDs was confirmed by fluorescence, UV-vis, resonance light scattering, and FT-IR. The Stern-Volmer analysis and fluorescence lifetime experiment disclosed that the quenching of CQDs by DNF was a static quenching process. Based on the interaction, a novel fluorescence method for determining DNF was established. Under optimized experimental conditions, the concentration of DNF had a linear relationship with the ratio of fluorescence intensity. The linear range was from 0.20 to 56.62 μg mL^-1, whereas the limit of detection (LOD) and limit of quantification (LOQ) were 17.68 and 58.93 ng mL^-1, respectively. The method was successfully applied to determine DNF in potato, sweet potato, apple, pear, and cabbage samples.