Facile electrochemical determination of 5-fluorouracil as an important anti-cancer drug using CeO₂-CuO nanocomposite modified carbon paste electrode

In this study, a carbon paste electrode was modified with a composite material of CeO2-CuO to fabricate an electrochemical sensor. The fabricated sensor was then employed for the analysis of 5-fluorouracil (5-FU), an important anticancer drug, in a phosphate buffer solution (PBS) with pH 7.0, using cyclic voltammetry (CV) and differential potential voltammetry (DPV) techniques. The effect of critical parameters such as catalyst loading, scan rate, type, and pH of the supporting electrolyte on the electrochemical responses of the modified electrode was assessed and optimized. The electrochemical response of the fabricated sensor towards 5-FU remained unaffected in the presence of various potent interfering compounds, indicating its anti-interference capability. The DPV responses of the prepared sensor was linear with the concentration of 5-FU in the range of 0.1-1.0 mu mol L-1 and 1.0-40.0 mu mol L-1 under optimal experimental conditions, with a detection limit of 0.01 mu mol L-1. The electrochemical sensor developed in this study was employed to determine 5-FU in human urine samples with the acceptable recovery. The fabricated sensor demonstrated favorable characteristics such as high sensitivity, repeatability, reproducibility, and stability.