Abstract
In the pharmaceutical field, analytical chemistry is evolving and one area that is experiencing enthusiasm is the design and implementation of solid contact ion-selective electrodes. We have developed two potentiometric sensors for the selective assay of a widely used drug diclofenac sodium. Diclofenac sodium was targeted in one of its most recommended dosage forms (Arthrotec® tablets) in the presence of misoprostol. A cost-effective copper printed circuit board as a substrate has been coated with a PVC sensing membrane to fabricate sensor I. Hydrophobic carbon nanotubes (CNTs) have been modified through in situ reduction of pentafluorophenyl diazonium using sodium borohydride. An interlayer of the modified CNTs was inserted as a transducer layer between the Cu substrate and the ion-sensing membrane in sensor II to enhance its electrochemical performance and stability. The microfabricated electrodes demonstrated encouraging outcomes upon the direct assay of diclofenac sodium in combination with misoprostol and other additives without sample preparation steps. The responses presented a linear Nernstian pattern in the range of 1.0 × 10−4 to 1.0 × 10−2 mol l−1 with a slope of −58.2 and −58.4 mV/decade for sensors I and II, consequently. Finally, the sustainability of the developed technique was assured using advanced green metrics.
Publisher
The Electrochemical Society