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

Abstract

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 μM and 1–60 μM with detection limits of 0.11 μM 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.