A highly sensitive and selective electrochemical sensor based on PIL-Br@ZIF-8/MXenes nanocomposite for 4-aminophenol detection in diverse food matrices

The sensitive detection of trace food contaminants is imperative for food safety. This work reports the rational design of a poly (ionic liquid) bromide@zeolitic imidazolate framework-8/MXenes (PIL-Br@ZIF-8/MXenes) nanocomposite, in which a ZIF-8 core is functionalized with a poly (ionic liquid) shell and then assembled with MXenes into a 3D conductive network. This architecture leverages the synergistic properties of its components: the porous ZIF-8 provides superior molecular load capacity, the MXenes offer exceptional electrical conductivity and additional active sites, and the PIL-Br enhances ion transport, thereby significantly improving the electrode's sensitivity and selectivity. The developed sensor demonstrates excellent performance for 4-aminophenol detection across five diverse food matrices, with a broad linear range (0.5–75 μM) and an ultralow limit of detection (2.822 nM). Our study provides a novel and effective strategy for fabricating advanced sensing platforms for food safety monitoring. • An electrochemical sensor for the detection of 4-aminophenol in food residues was developed. • The sensor has high sensitivity, good selectivity and anti-jamming ability. • The sensor was used for the detection of 9 food samples. • The practicability of the UV–Vis method was verified in the detection of complex food samples.