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 Ti 3 C 2 MQDs (EDA-MQDs) was designed to selectively and sequentially detect Fe 3+ 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 Fe 3+ and EDA-MQDs, resulting in fluorescence quenching at 460 nm. Meanwhile, on account of the strong chelation between imidazole group on histamine and Fe 3+ , the Fe 3+ 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 Fe 3+ 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 μM and 1–60 μM with detection limits of 0.11 μM and 46 nM for Fe 3+ and histamine, respectively. This work provided a highly effective tool for selective detecting histamine and Fe 3+ as well as tendered a novel strategy for functionalized Ti 3 C 2 MQDs in food analysis.