Preserving food quality: Electrochemical detection of synthetic food antioxidant, propyl gallate in processed foods using ternary component layered double hydroxide/graphene aerogel synergy

Fueled by the mounting demand from convenience-oriented consumers, the contemporary food industry increasingly relies on specialty chemicals to extend the shelf-life of processed food. Antioxidants such as propyl gallate (PG) are added to food products to avert lipid oxidation. Existing methods for monitoring PG often lack the required sensitivity and accuracy for real-time applications. Our work demonstrates enhanced sensitivity and selectivity through the synergistic combination of transition metal-based ternary layered double hydroxide (LDH) and graphene aerogel (GA) coated on a disposable screen-printed carbon electrode (SPCE). Introducing multi-metal-based LDH improves the electrochemical stability compared to virgin LDH structures. Using NiFeCu-LDH anchored to porous GA leading to high specific surface area and enhanced electron transfer, we explore the electrochemical conversion of PG at the modified SPCE using various electrochemical techniques. Differential pulse voltammetry showed a wide linear range from 0.02 to 279.1 μM and a limit of detection of 0.004 μM. Importantly, our work chronicles new insights into using Deep Eutectic Solvent (DES) systems for the green synthesis of LDHs. The developed electrochemical sensor was successfully used to assay PG in real food matrices, achieving recoveries of ±97.60–99.2%.