A new sensor architecture based on carbon Printex 6L to the electrochemical determination of ranitidine

Abstract

A glassy carbon electrode (GCE) modified with carbon Printex 6L (Printex6L/GCE) as a novel sensor is proposed. A morphological study was carried out using scanning electron microscopy, and an electrochemical characterization of the proposed electrode was performed by cyclic voltammetry (CV) using [Fe(CN)6]4− as a redox probe. With the incorporation of the carbon Printex 6L film onto the GCE surface, the [Fe(CN)6]4− analytical signal was substantially increased and the difference between the oxidation and reduction potentials (ΔE p) decreased, a characteristic of the electrocatalytic effect. Furthermore, the use of carbon Printex 6L film resulted in an 84 % increase in the oxidation current and a 123 % increase in the reduction current. Faster charge transfer was observed at the proposed electrode/electrolyte interface during CV when compared with GCE. The Printex6L/GCE was tested for ranitidine (RNT) sensing and showed a decrease in the working potential and an increase in the analytical signal, when compared with GCE, again demonstrating an electrocatalytic effect. Under optimized experimental conditions, the developed square-wave adsorptive anodic stripping voltammetry (SWAdASV) method presented an analytical curve that was linear in RNT concentration range from 1.98 × 10−6 to 2.88 × 10−5 mol L−1 with a detection limit of 2.44 × 10−7 mol L−1. The developed Printex6L/GCE was successfully applied to the determination of RNT concentrations in human body fluid samples (urine and serum).