ELECTROCHEMICAL BIO-SENSING OF CAFFEIC ACID IN REAL SAMPLES USING Ag@g-C₃N₄ COMPOSITE MATERIAL FOR HIGHLY SELECTIVE AND SENSITIVE APPLICATIONS

Abstract

Caffeic acid (CA) is recognized as a phenolic antioxidant with anti-inflammatory, antibacterial, anticarcinogenic and immunomodulatory effects, positioning it as a key representative of hydroxycinnamic acids found in wine. Caffeic acid is detectable in various products including fruits, vegetables, wine, olive oil and coffee. Numerous studies suggest that eating foods rich in CA may provide protection against cancer by inhibiting the production of nitro compounds (including nitrosamines and nitroamides) that are primary contributors to this disease. The goal of this research is to create an enzyme-based biosensor for the detection of caffeic acid utilising silver nanoparticles on a graphitic carbon nitride (Ag@g-C3N4) nanocomposite. The Ag@g-C3N4 nanocomposite was synthesised through chemical methods and applied to an indium tin oxide-coated glass substrate via electrophoretic deposition. The resulting biosensor demonstrates a favourable linear range from 1.0 pM to 1.0 μM with a detection limit of 0.75 pM and displays no significant interference from glucose, ascorbic acid, urea and mixtures. Additional efforts were made to validate the biosensor using real samples from coffee, green tea and black tea. The electrochemical findings indicated that the proposed biosensor is a dependable analytical tool for assessing the quality of caffeic acid in food samples.