Electrochemical bio-sensor of caffeine in food beverages on using silver vanadium oxide decorated in graphitic carbon nitride (AgVO@g-CN) Nano composite modified glassy carbon electrode

Abstract

The silver vanadate AgVO@g-CN was synthesized by the Co-precipitation method for the first time. The electrocatalytic potential of the AgVO@g-CN nanocomposite is investigated using cyclic voltammetry and differential pulse voltammetry to detect caffeine (CAF). The linear relationship between peak current and CAF concentration has been determined to be in the 6.5 to 255 μM wide linear range, with a lower detection limit of 0.038 μM. The sensitivity of produced electrode was 5.87 μAμM−1 cm−1. The successful application of the modified AgVO@g-CN nanocomposite electrode for CAF detection demonstrates operational stability, and the novel technique displayed good repeatability and reproducibility. Caffeine levels in commercial coffee, Red Bull, and Coca-Cola were successfully determined using the proposed sensor. The results obtained clearly show the capability of sensing and possible application of AgVO@g-CN nanocomposite for real-time electrochemical detection of CAF.