Graphene/Nafion composite film modified glassy carbon electrode for simultaneous determination of paracetamol, aspirin and caffeine in pharmaceutical formulations

A graphene-Nafion composite film was fabricated on the glassy carbon electrode (GR-NF/GCE), and used for simultaneous determination of paracetamol (PAR), aspirin (ASA) and caffeine (CAF). The electrochemical behaviors of PAR, ASA and CAF were investigated by cyclic voltammetry and square-wave adsorptive anodic stripping voltammetry. By using stripping one for simultaneous determination of PAR, ASA and CAF, their electrochemical oxidation peaks appeared at +0.64,1.04 and 1.44 V, and good linear current responses were obtained with the detection limits of 18 ng mL(-1) (1.2 x 10(-9) M), 11.7 ng mL(-1) (6.5 x 10(-8) M) and 7.3 ng mL(-1) (3.8 x 10(-8) M), respectively. Finally, the proposed electrochemical sensor was successfully applied for quantifying PAR, ASA and CAF in commercial tablet formulations. (C) 2016 Elsevier B.V. All rights reserved.