Preparation of the Ratio-Fluorescence Probe Based on O-phenylenediamine for Selective and Sensitive Detection of Cu2+

A fluorescent probe based on the functionalized carbon quantum dots (CQDs-OPD) was successfully synthesized for selective and sensitive detection of Cu 2+ . Using O-phenylenediamine (OPD) as the carbon resource and N,N-dimethylformamide (DMF) as the solvent, the CQDs-OPD was prepared by the hydrothermal method. The fluorescence mechanism of CQDs-OPD was studied by the intercept method. Furthermore, the probe was characterized by TEM, UV–Vis, FT-IR and Zeta potentiometric analysis, the fluorescent probe exhibits a good fluorescence properties and stability. The prepared ratio-fluorescent probe shows a good linear range from 0 to 25 μmol/L with a lower LOD of 40 nmol/L. Moreover, the probe also has been successfully applied to the detection of Cu 2+ in the real samples with the recovery rate of 96.92–97.80% and the RSD of less than 2.0%.