Electrochemical sensing of Tryptophan using a Zn-doped perovskite modified glassy carbon electrode in Food Samples

This study presents a novel electrochemical sensor based on a LaFe۰.۹Zn۰.۱O۳ modified glassy carbon electrode for the sensitive and selective detection of Tryptophan. The morphology of the perovskite was examined using scanning electron microscopy (SEM), high-resolution transmission electron microscopy (HR-TEM), energy-dispersive X-ray spectroscopy (EDX), X-ray photoelectron spectroscopy (XPS), X-ray diffraction (XRD), and Fourier-transform infrared spectroscopy (FTIR). Additionally, EDX was employed to confirm the presence of elements within the perovskite structure. The Zn-doped lanthanum ferrite nanostructure exhibited enhanced electrocatalytic activity, facilitating the efficient electrochemical oxidation of Tryptophan. Cyclic voltammetry (CV) and differential pulse voltammetry (DPV) were employed to investigate the electrochemical behavior and quantify Tryptophan. Using differential pulse voltammetry, the sensor achieved a broad linear range (۲-۱۹۰ μM) with a low detection limit of ۱.۳۶ μM, while demonstrating remarkable selectivity against common interfering species, including Ascorbic acid, Dopamine, and Uric acid. The practical application was validated through successful quantification of Tryptophan in complex food matrices. This cost-effective and robust sensing platform shows significant potential for nutritional analysis and food quality monitoring, offering advantages over conventional methods in terms of simplicity and portability. The strategic doping of zinc in the perovskite structure effectively enhanced conductivity while maintaining excellent catalytic performance for Tryptophan detection in real samples.

کلیدواژه ها:

Tryptophan ، electrochemical sensor ، perovskite ، glassy carbon electrode