Ultrasensitive Detection of Propyl Gallate and Vanillin in Food Products Using a Ag Decorated MXene/CdTe Quantum Dots Based Electrochemical Sensor

The use of food additives and flavoring agents above allowed limits poses serious risks to human health. The unregulated or excessive usage of food additives such as PG and VA can lead to toxicity, allergic reactions, and long-term health complications, emphasizing the need for strict regulatory oversight and monitoring. In this study, we propose a Ag-decorated Ti3C2Tx/CdTe QDs nanocomposite electrochemical sensor for the simultaneous detection of PG and VA. The Ag-decorated Ti3C2Tx/CdTe QDs nanocomposite sample was prepared by a facile hydrothermal method. The successful formation of pristine and composite samples was validated through several physicochemical techniques. The structural features of Ag-decorated Ti3C2Tx/CdTe QDs encourage hotspot formation at the interface between nanosheets, nanodots, and nanoparticles. It enhances electrocatalytic properties, increases the surface area, and provides more active sites that interact with food additives. Moreover, this study introduces an electrochemical sensor based on the glassy carbon electrode modified with Ag-decorated Ti3C2Tx and CdTe QDs. The synergistic interaction between the layered structure of Ti3C2Tx and nanodot-sized CdTe QDs, combined with the enhanced conductivity provided by Ag nanoparticles, facilitates efficient electron transfer and improved sensitivity. The proposed Ag-decorated Ti3C2Tx/CdTe QDs/GCE sensor demonstrated superior sensitivity (15.92 μA μM–1 cm–2 for PG and 6.06 μA μM–1 cm–2 for VA), a wide linear range (0.1 to 400 μM), and a lower detection limit (3.2 nM for PG and 8.05 nM for VA). The proposed sensor’s real-time applicability was further validated through the detection in chicken meat and ice cream samples, yielding satisfactory recovery rates via the standard addition method. These findings highlight the Ag-decorated Ti3C2Tx/CdTe QDs/GCE nanocomposite as a potential electrocatalyst for food additive detection.