A New Cellulose-Based Fluorescent Probe for Specific and Sensitive Detection of Cu(2+) and Its Applications in the Analysis of Environmental Water

In this work, a novel fluorescent probe CMC−GE−AQ with an effective sensitive detection ability for Cu(2+) was synthesized and constructed by using carboxymethyl cellulose (CMC) as the skeleton and 8-aminoquinoline (AQ) as the fluorophore. This probe exhibited a highly specific “turn-off” fluorescence response to Cu(2+), and the fluorescence color changed from bright orange to colorless after adding Cu(2+). The probe could selectively detect Cu(2+) in a complex environment and its detection limit (LOD), the binding constant (K(a)) and the numbers of binding sites (n) were calculated to be 6.4 × 10(−8) mol L(−1), 1.7 × 10(6) mol(−1) L and 1.2, respectively. The sensing detection mechanism was confirmed by X-ray photoelectron spectroscopy (XPS) and density functional theory (DFT) calculations. In addition, the probe CMC−GE−AQ was successfully applied to detect Cu(2+) in real water samples, and CMC−GE−AQ-based fluorescent microspheres can serve as a convenient tool for the detection of Cu(2+).