Square-wave adsorptive anodic stripping voltammetric determination of ramipril using an electrochemical sensor based on nanostructured carbon black

Abstract

A novel and alternative electroanalytical method for the determination of ramipril (RAM) using a glassy carbon electrode (GCE) modified with nanostructured carbon black (CB) is reported. The electrochemical sensor was obtained by a simple drop coating strategy, and the designed architecture consisted of a GCE modified with CB within a dihexadecylphosphate film. The remarkable electrocatalytic activity of CB towards RAM electrooxidation was verified, and from different electrochemical assays, the number of electrons involved in the RAM oxidation was determined and, therefore, an electrooxidation reaction for RAM molecules was proposed. Under optimised experimental conditions, RAM was determined by square-wave adsorptive anodic stripping voltammetry. The analytical curve of RAM was linear from 1.98 × 10⁻⁶ to 2.42 × 10⁻⁵ mol L⁻¹, with a limit of detection of 4.27 × 10⁻⁷ mol L⁻¹. The proposed voltammetric procedure was successfully applied for the determination of RAM in pharmaceutical products and biological samples.