Sensitive, Selective and Reliable Detection of Fe(3+) in Lake Water via Carbon Dots-Based Fluorescence Assay

In this study, C-dots were facilely synthesized via microwave irradiation using citric acid and ethylenediamine as carbon precursors. The fluorescence emissions of the C-dots could be selectively quenched by Fe(3+), and the degree of quenching was linearly related to the concentrations of Fe(3+) presented. This phenomenon was utilized to develop a sensitive fluorescence assay for Fe(3+) detection with broad linear range (0–250, 250–1200 μmol/L) and low detection limit (1.68 μmol/L). Most importantly, the assay demonstrated high reliability towards samples in deionized water, tap water and lake water, which should find potential applications for Fe(3+) monitoring in complicated environments.