Electrochemical sensing of caffeic acid antioxidant in wine samples using carbon paste electrode amplified with CdO/SWCNTs

An electrochemical sensor was introduced as an analytical tool for monitoring caffeic acid in food samples. This analytical tool was amplified by cadmium oxide decorated on single wall carbon nanotubes as a new catalyst and showed a powerful ability to sensing of caffeic acid in food products. The presence of cadmium oxide decorated on single wall carbon nanotubes catalyst improved the oxidation signal of caffeic acid about 2.4 times at optimum conditions. The pH investigation confirmed that the redox reaction of caffeic acid was pH dependent and showed maximum sensitivity at pH 7.0. The paste electrode amplified with cadmium oxide decorated on single wall carbon nanotubes was successfully monitored caffeic acid in the concentration range 0.02–200 µM with a detection limit of 9.0 nM, respectively. The standard addition strategy showed a recovery range of 97.96 – 102.59 % to the measurement of caffeic acid in fruit juice, white and red wine that was acceptable for the fabrication of a new analytical tool in food monitoring.