Reusable polymer-based fluorescent sensor nanoprobe for selective detection of Cd2+ ions in real water sources

Abstract

Cadmium, which is classified as a highly toxic metal among all heavy metals, poses a threat to the environment and human health, even at trace levels. In this study, for the first time in the literature, a fluorescent sensor nanoprobe that can selectively detect Cd²⁺ ions in different real water sources has been developed by attaching a CdTe QD–4 amino TEMPO complex to an iCVD deposited cross-linked copolymer surface with high mechanical strength. Under the appropriate conditions such as pH, concentration, type of solvent and reaction time, the interaction between Cd²⁺ ions and the polymer-based QD–4AT nanoprobe was enhanced, and the detection of this target ion with high selectivity was made possible even in the environments with complex structures containing different heavy metal ions. The limit of detection (LOD) of Cd²⁺ ions with this proposed polymer sensor nanoprobe was found to be 0.195 μM by using the linear detection region of 0.0784–2.5 μM (R² > 0.997). In the literature, several sensor probes have been developed for the detection of Cd²⁺ ions and have only been investigated for single use in liquid media. The polymer sensor nanoprobe developed in this study has high sensitivity and selectivity in terms of detection limit compared to the previous ones, and the results obtained from the multiple use studies indicate that this nanoprobe can be used more than once for ion detection without loss of performance. This is a brand-new product for fluorescence sensing studies and will be a great source of inspiration for them.