First Electrochemical Investigation of the Potent Antibiotic Rifapentine: Enhanced Voltammetric Detection Using a Boron-Doped Diamond Electrode in Tween-Mediated Measurements

Abstract

A non-modified boron-doped diamond electrode provided excellent electrochemical sensing capabilities for detecting rifapentine (RPT) using square-wave voltammetry. RPT was measured by cyclic voltammetry with phosphate buffer solutions (PBS, 0.1 M, pH 2.5), which exhibited irreversible behavior with distinct oxidation peaks at approximately +0.53 V (PA1) and + 1.08 V (PA2). The oxidation of RPT is strongly influenced by both pH and the choice of supporting electrolytes. The addition of the non-ionic surfactant Tween 20 to the supporting electrolyte notably enhanced the anodic peak currents of RPT. RPT was measured using two anodic peaks. Under optimal experimental conditions and instrumental factors, the current response for RPT exhibited a linear relationship within the range of 1 to 25.0 mu g mL-1 (1.1 x 10-6-2.9 x 10-5 M), with detection limits of 0.29 mu g mL-1 (3.3 x 10- 7 M) for PA1 (+0.48 V) as well as 0.19 mu g mL-1 (2.2 x 10- 7 M) for PA2 (+1.04 V) in PBS (pH 2.5). Finally, RPT in a pharmaceutical formulation was accurately quantified using the proposed methodology. This represents, to the best of our knowledge, the first electroanalytical method for determining RPT.