Ethylenediamine functionalized MoS2 quantum dots for terramycin sensing in environmental water and fish samples

In this paper, a simple and effective fluorescent system was fabricated for sensitive detection of terramycin using ethylenediamine functionalized MoS 2 quantum dots (EDA-MoS 2 QDs) as probes. The monodisperse EDA-MoS 2 QDs were synthesized by microwave-assisted one-step bottom-up strategy. The obtained EDA-MoS 2 QDs have excellent water solubility and ultra-small sizes with an average diameter of 1.72 nm. In addition, they show strong fluorescence with high fluorescence quantum yield (22.62%). The existence of terramycin can effectively quench the fluorescence of EDA-MoS 2 QDs based on intermolecular charge transfer and aggregation-induced quenching mechanism. The fluorescence quenching efficiency is linearly dependent on the concentration of terramycin. The EDA-MoS 2 QDs exhibit high sensitivity for terramycin detection with a detection limit of 0.5 nM. Moreover, the EDA-MoS 2 QDs modified filter papers quickly determine the trace amounts of terramycin in fresh fish. The fluorescence quenching-induced color change can be observed by the naked eye under the UV light. The sensor system based on EDA-MoS 2 QDs has the good analytical performance, and can be applied to environmental water and food security monitoring.