A novel electrochemical sensor based on reduced graphene oxide decorated with gold nanoparticles for voltammetric sensing of amlodipine in human urine

Calcium channel blockers were proposed to provide the benefit of heart rate control, which could potentially enhance an athlete’s shooting performance during Olympic competition.The present work represented a precise, accurate, sensitive, and fast differential pulse voltammetric (DPV) approach for determining amlodipine besylate (AML) in human urine. The fabricated sensor was based on a carbon paste electrode amended with reduced graphene oxide (rGO) that had been decorated with gold nanoparticles through a covalent diazonium linker. The modified reduced graphene oxide-gold nanoparticles nanocomposites electrode (Au-NPs@rGO) demonstrated a detectable improvement in the anodic peak current of amlodipine besylate, with enhanced sensitivity, selectivity, high stability, and a low detection limit. As a result, it served as a useful methodology for the precise and reliable determination of amlodipine besylate in pharmaceuticals and biological samples. The ideal conditions were identified at a pH of 6.0 after studying the impact of pH and scan rate on the peak current and potential. A linear response was attained over the concentration range of 2.0 × 10⁻6 to 1.4 × 10⁻5 mol L−1 for amlodipine besylate. The proposed sensor exhibited a rapid response time and high sensitivity. The approach demonstrated potential applicability in quality control, doping detection, and routine analysis of amlodipine besylate in single or ternary pharmaceutical formulations. An assessment of greenness indicated that the methodology provided superior green analysis. Graphical abstract: (Figure presented.) © The Author(s), under exclusive licence to Springer Nature B.V. 2024.