WO 3 decorated graphene nanocomposite based electrochemical sensor: A prospect for the detection of anti-anginal drug.

Ranolazine (RZ) is an anti-anginal drug with a distinct mechanism of action and widely employed in patients with chronic angina. Its measurement is essential in clinical environment to ensure adequate drug level and understand the redox mechanism which gives an idea of in-vivo fate of the drug. In view of this, an exemplary voltammetric approach is proposed here for determination of RZ utilizing glassy carbon electrode (GCE) fabricated with WO ₃ decorated graphene nanocomposite. The structural and morphological characterizations of modifier were made by employing XRD, FESEM, EDAX, HRTEM, XPS, Raman and FT-IR spectroscopy which revealed successful formation of the nanocomposite. As a result of high electrical conductivity and large effective surface area of WO ₃ nanoparticles and graphene nanosheets, the developed sensor WO ₃ /Graphene/GCE displayed effectual and unrelenting electron interceding behavior exhibiting higher peak currents at lower potentials for RZ oxidation. Using square wave voltammetry, the drug showcased well-defined voltammetric response in Britton-Robinson buffer at pH 4.5 in concentration range from 0.2-1.4 μM and 1.4-14 μM with the low detection limit of 0.13 μM. The developed protocol was then implemented successfully to quantify RZ in commercially accessible pharmaceutical tablets with satisfactory recovery (99.8%-100.2%). The experimental results illustrated the applicability of the fabricated sensor for drug quality control and clinical analysis along with pharmacokinetic studies.
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