Voltammetric oxidation and determination of loop diuretic furosemide at a multi-walled carbon nanotubes paste electrode

Electrochemical oxidation of loop diuretic furosemide (4-chloro-2-(furan-2-ylmethylamino)-5-sulfamoylbenzoic acid) was studied in 5.0 pH with 0.04 M Britton–Robinson buffer as supporting electrolyte at 25 ± 0.1 °C at a multi-walled carbon nanotubes-paraffin oil paste electrode (CNTPE) using cyclic and differential-pulse voltammetric (DPV) techniques. The electrochemical process was observed to be adsorption controlled, irreversible and involving two-electron oxidation. Effects of anodic peak potential (Epa), anodic peak current (Ipa) and heterogeneous rate constant (k0) have been discussed. Under optimal conditions, the peak current was proportional to furosemide concentration in the range of 8.0 × 10−6 to 2.0 × 10−4 M with a detection limit of 2.9 × 10−7 M by differential pulse voltammetry. A differential pulse voltammetric method with good precision and accuracy was developed for the determination of furosemide in pharmaceutical formulations and urine as a real sample.

Multi-walled carbon nanotubes paste electrode has been successfully used for the oxidation of FUR in BR buffer solution (pH = 5.0). Based on the study, influence of several physico-chemical parameters like potential scan rate, pH and concentration were investigated.Figure optionsDownload as PowerPoint slideHighlights
► CNTPE has been successfully used for the electro-oxidation of FUR.
► Cyclic and differential-pulse voltammetric techniques are used.
► Effects of Epa, Ipa and k0 have been discussed.
► DPV method was developed for the determination of FUR.