Electrochemical profiling and analytical method validation of bismuth subsalicylate in marketed pharmaceutical formulation via cyclic voltammetry

Abstract

Bismuth subsalicylate (BSS) is a metallopharmaceutical drug commonly used as an antidiarrheal agent. Traditional analytical methods for metallopharmaceutical often require long analysis times, high reagent use, and costly equipment. To address these issues, a cyclic voltammetry (CV) method was developed for BSS determination. The measurements used a potentiostat with a glassy carbon electrode (GCE) and Britton-Robinson Buffer (0.04 M, pH 9.0) as the supporting electrolyte. A platinum auxiliary electrode and Ag/AgCl (3 M KCl) as the reference electrode, completed the setup. BSS showed an irreversible redox reaction at the GCE. Optimal CV parameters included a scan rate of 0.05 V/s and potential range from -0.1 to 1.5 V. The method showed linearity from 2 to 18 ppm with an R² of 0.997. Limits of detection and quantification were 0.159 ppm and 0.483 ppm, respectively. Tablet analysis gave recoveries with mean content (%) ± SD ranging from 97.13 ± 1.82 to 99.79 ± 1.91. The method is precise, reproducible, and complies with ICH guidelines, making it suitable for routine BSS drug analysis.