An efficient off-on fluorescence probe based on EDA functionalized Ti3C2 MXene quantum dots for sequential detection of Fe3+and histamine

MXene quantum dots (MQDs) exhibit vast application prospection the field of fluorometric sensing, but how to efficiently utilize MQDs for the selective detection of two components still remains a challenge. Herein, an off-on fluorescence sensor based on ethylenediamine-functionalized Ti3C2 MQDs (EDA-MQDs) was designed to selectively and sequentially detect Fe3+ and histamine. EDA-MQDs were synthesized using a facile ultrasonic-hydrothermal method and exhibited bright blue fluorescence with a quantum yield up to 21.12 %. Inner filter effect occurred between Fe3+ and EDA-MQDs, resulting in fluorescence quenching at 460 nm. Meanwhile, on account of the strong chelation between imidazole group on histamine and Fe3+, the Fe3+ concentration in the system was reduced, so the fluorescence of EDA-MQDs was recovered. Thus, the as-designed fluorescence probe was used for dual-detection of Fe3+ and histamine in real samples with satisfactory sensitivity and selectivity. The proposed sensing method was verified to possess good linear response in the range of 1-100 mu M and 1-60 mu M with detection limits of 0.11 mu M and 46 nM for Fe3+ and histamine, respectively. This work provided a highly effective tool for selective detecting histamine and Fe3+ as well as tendered a novel strategy for functionalized Ti3C2 MQDs in food analysis.