Electrochemically Activated Screen-Printed Graphene Electrochemical Sensor for Daidzein Determination in Edible Peanut Oils

Abstract

In this work, we designed a novel and simple electrochemical approach for the determinationof daidzein antioxidant (Dz) in peanut oil samples. The Dz determination was basedon anodic stripping linear voltammetry using screen-printed graphene electrodes (SPGEs)activated in acidic media, where a strong adsorption of Dz on activated graphene wasobtained. In this regard, electroanalytical parameters such as the scan rate, supportingelectrolyte, pH, and accumulation step were optimized to ensure the best conditions for theselective and sensitive Dz quantification. The electrochemical method developed for the determination of Dz exhibits a linear behavior of the anodic peak current in the concentrationrange from 0.05 to 1 μM, with a limit of detection of 0.012 μM. The electrochemical sensordemonstrated to the capacity to quantify Dz in peanut oil samples at low concentrationswithout the necessity of an extensive sample pretreatment. Therefore, the electrochemicalmethod proposed can be used as a new portable analytical tool for the in situ quality controlof peanut oil samples.