Voltammetric analysis and electrochemical behavior of an antibiotic drug Nifuroxazide on a boron-doped diamond electrode in the existence of a cationic surfactant

In this work, the voltammetric sensing of nifuroxazide (NFX) was assessed utilizing a boron-doped diamond (BDD) electrode that underwent electrochemical pretreatment, enhancing its surface activity. Cyclic voltammograms of NFX revealed well-defined, single, and irreversible peaks at 0.94 V (vs. Ag/AgCl) in a 0.04 M BrittonRobinson (BR) buffer solution at pH 6.0. The oxidation peaks of NFX were found to be pH-dependent across a range from 2.0 to 12.0. Introducing a cationc surfactant (CTAB; cetyltrimethylammonium bromide) into the selected electrolyte increased the anodic peak currents of NFX. Under optimized conditions, a linear relationship was established for NFX quantification in 0.04 M solution of BR buffer (pH 6.0) containing 2x10-4 M CTAB at +1.02 V (vs. Ag/AgCl). The linear range spanned from 0.05 to 2.0 mu g mL-1 (1.8x10-7 - 7.2x10-6 M), with a detection limit of 0.013 mu g mL-1 (4.7x10-8 M). The NFX concentration in the drug formulation was successfully quantized using this method.