Multifunctional fluorescent sensors for independent detection of multiple metal ions based on Ag nanoclusters

Selective and sensitive detection of multiple metal ions is significant for biological researches and environmental monitoring, because the abnormal metal ions levels have potential damage to the human body and environment. In this study, a fluorescent sensing platform based on Ag nanoclusters has been established for independent detection of Hg2+, Cu2+, and Fe3+ ions in a solution. The interference of the fluorescence induced by coexistent metal ions was removed by altering buffers with different pH and using different masking agents. Moreover, the detection mechanism is discussed in detail, which provides a valuable reference for the detection of heavy metal ions with metal nanomaterials. This sensor exhibits a high selectivity and sensitivity, and the linear ranges for Hg2+, Cu2+, and Fe3+ detection are 0.05-9, 0.05-18, and 0.1–18 μM with the corresponding detection limits of 12, 27, and 50 nM, respectively. Furthermore, this method was successfully used for analyzing the three metal ions in environmental and biological samples.