An electrochemical platform of bimetallic oxide (Sb2O3@WO3) nanoparticles and carbon nanotubes for the sensitive determination of metaproterenol in pharmaceuticals and biological samples

Abstract

In this study, a modified electrode was prepared using a composite of carbon nanotubes (CNTs), nanoparticles of antimony oxide (Sb2O3) and tungsten oxide (WO3) at the surface of glassy carbon electrode (GCE). The active surface area was 0.0863, 0.2580, 05780, 0.6150 and 0.8260 cm2 for unmodified GCE, CNTs/GCE, WO3-CNTs/GCE, Sb2O3-CNTs/GCE and Sb2O3@WO3-CNTs/GCE, respectively. Several electrodes are compared with respect to the oxidation of metaproterenol. No remarkable peaks were observed for metaproretenol at unmodified GCE. However, the oxidation of metaproterenol occurred at 0.677 V, 6.75 V, 6.73 V and 0.670 V at CNTs/GCE, WO3-CNTs/GCE, Sb2O3-CNTs/GCE and Sb2O3@WO3-CNTs/GCE, respectively. The proposed method produces a linear dynamic concentration range of 5.2 × 10−8–2.7 × 10−6 M with a detection limit of 6.6 × 10−9 M for metaproterenol. The method was satisfactorily applied for the determination of metaproterenol in tablets and urine sample.