Simultaneous Determination of Caffeic Acid and Ferulic Acid Using a Carbon Nanofiber-Based Screen-Printed Sensor

This work aims to achieve the simultaneous qualitative and quantitative determination of two hydroxycinnamic acids (ferulic acid and caffeic acid) from standard solutions and from a phyto-homeopathic product using a carbon nanofiber-based screen-printed sensor (CNF/SPE). The two compounds are mentioned in the manufacturer's specifications but without indicating their concentrations. The stability and reproducibility of the CNF/SPE were found to be effective and the sensitivity was high for both caffeic acid-CA (limit of detection 2.39 x 10(-7) M) and ferrulic acid-FA (limit of detection 2.33 x 10(-7) M). The antioxidant capacity of the compounds in the analyzed product was also determined by the DPPH (2,2-diphenyl-1-picrylhydrazyl) method. The electrochemical method was efficient and less expensive than other analytical methods; therefore, its use can be extended for the detection of these phenolic compounds in various dietary supplements or pharmaceutical products.

Automated summary

This study aimed to simultaneously qualitatively and quantitatively determine two hydroxycinnamic acids using a carbon nanofiber-based screen-printed sensor. The method was found to be stable, reproducible, and sensitive, making it suitable for detecting these compounds in various dietary supplements or pharmaceutical products.