Nanoflakes of cobalt oxide for highly sensitive sensing of two orally iron chelating drugs deferasirox and deferiprone

The synthesis of nanoflakes of cobalt oxide via electrodeposition onto platinum electrode surface was reported. The morphology of the electrodeposited thin film was studied by means of scanning electron microscopy and atomic force microscopy techniques and the electrochemical characteristics were investigated using cyclic voltammetry. The applicability of the synthesised nanoflakes of cobalt oxide to electrocatalytic oxidation of two orally administered iron chelating drugs (deferasirox, ICL670 and deferiprone, CP20) was evaluated in an alkaline solution. The results indicate that the drugs were oxidised via oxyhydroxide species immobilised on the electrode surface through an electrocatalytic mechanism. The catalytic rate constants and the diffusion coefficients of the drugs were determined. A sensitive, simple and efficient amperometric procedure was developed for the analysis of deferasirox and deferiprone, with detection limits of 6.67 and 2.52 µM, respectively. The electrode was also used for the direct assay of deferasirox and deferiprone tablets and determination of their main metabolites in human serum and urine.