Development of a new spectrofluorimetric method for the determination of trifluralin in water and vegetable samples using carbon nanodots prepared from olive pits

This study presents an innovative approach that integrates sustainable material production and environmental monitoring by employing carbon nanodots (CNDs) derived from olive pits for the detection of the pesticide trifluralin. The CNDs, synthesized via a pyrolysis method, were characterized using various techniques, including UV–Vis spectroscopy, fluorescence spectroscopy, Fourier Transform Infrared (FT-IR) spectroscopy, X-ray Photoelectron Spectroscopy (XPS), Raman spectroscopy, Transmission Electron Microscopy (TEM), High-Resolution Transmission Electron Microscopy (HR-TEM), and X-ray Diffraction (XRD). The fluorescent CNDs exhibited fluorescence quenching upon interaction with trifluralin, and the quenching mechanism was investigated using Stern–Volmer analysis. Studies conducted at different temperatures revealed that the quenching mechanism was a static nature. In selectivity analyses of the CNDs, no significant interaction was observed with other pesticides. The spectrofluorimetric method developed for trifluralin determination was successfully applied to tap water, purple cabbage, and carrot samples. The results demonstrate that these nanodots, produced from waste olive pits, provide an environmentally friendly, rapid, selective, and sensitive fluorescence sensing platform suitable for water and food safety monitoring.