Electrochemical sensor based on CdTe QDs/Ti₃C₂T_x (MXene) was developed for the sensitive and selective detection of propyl gallate (PG) in food samples. The sensor demonstrated excellent sensitivity (0.465 µA µM⁻¹ cm⁻²), a low detection limit (52 nM), and a wide linear range (0.1-1000 µM). It also exhibited high stability, good repeatability (RSD = 1.36%), and effective performance in real-sample analysis. This study presents a promising approach for monitoring antioxidant residues in food safety applications.

Abstract

Antioxidants such as propyl gallate (PG) are commonly used to extend the shelf life of processed foods by preventing rancidity. However, excessive intake of PG can cause adverse health effects, including dermatitis and renal damage, underscoring the necessity for its effective monitoring and removal. In this study, we have developed an electrochemical sensor for PG detection based on cadmium telluride (CdTe) quantum dots (QDs) integrated titanium carbide (Ti₃C₂T_x, MXene). The CdTe QDs/Ti₃C₂T_x nanocomposite demonstrated significantly higher peak current intensity compared to other modified electrodes, as confirmed by cyclic voltammetry. The synergistic interaction between CdTe QDs and Ti₃C₂T_x enhanced the PG detection with a high sensitivity (0.465 µA µM⁻¹cm⁻²), low detection limit (52 nM), and wide linear range (0.1–1000 µM). Benefiting from a high surface area and efficient electron transfer, the CdTe QDs/Ti₃C₂T_x nanocomposite exhibited excellent repeatability, reproducibility and storage stability over 10 days, with relative standard deviation (RSD) of 1.36%. The practical applicability of the proposed electrochemical sensor was validated through real-time monitoring of PG in food samples, including chicken meat and noodle extracts. The standard addition method in real samples demonstrated a satisfactory recovery rate, highlighting the sensor's potential as a reliable tool for PG detection in food safety monitoring.