Dual-mode electrochemical and colorimetric detection of propyl gallate in food samples using a tungsten carbide anchored rGO aerogel nanocomposite modified SPCE.
Abstract
The wide-ranging use of artificial antioxidants in processed foods has generated growing concerns about food safety and quality assurance. Propyl gallate (PGT) is frequently utilized as an additive to prevent lipid oxidation and prolong the shelf life of food items; yet, excessive consumption may pose health hazards. Consequently, the advancement of quick and sensitive analytical techniques for the detection of PGT in food matrices is important. This study constructed a highly sensitive electrochemical sensor and colorimetric detection utilizing a tungsten carbide/reduced graphene oxide aerogel nanosheet (WCs/rGOANs) nanocomposite-modified screen-printed carbon electrode (SPCE) for the detection of PGT. The WCs/rGOANs nanocomposite was prepared via a solvothermal method, followed by composite integration, resulting in a conducting and catalytically efficient electrode interface. The physicochemical characterization validated the effective synthesis of the hybrid nanocomposite, while electrochemical analyses revealed improved electron transport characteristics and significant electrocatalytic activity for PGT oxidation. Under optimal conditions, the sensor demonstrated an extensive linear detection range of 0.039 μM to 1490.264 μM, while the linear range of colorimetric sensing was about 0.99 μM to 356.65 μM with a low detection limit of 2.4 nM, a limit of quantification of 0.008 μM, and a sensitivity of 35.48 μA μM-1 cm-2 for electrochemical sensing, and the LOD obtained for the colorimetric analysis was 0.0173 μM. The superior analytical performance is due to the synergistic interaction between WCs and rGOANs framework, which offers several active sites and enhances efficient charge transfer. Moreover, the developed sensor exhibited excellent selectivity, stability, and reproducibility, and was effectively utilized for the quantification of PGT in real food samples, including edible oils, noodles, and cookies. The nanocomposite facilitated dual-mode electrochemical and colorimetric sensing, providing a dependable platform for the assessment of antioxidant compounds in food matrices.