Voltammetric Determination of Cyproterone Acetate in Pharmaceutical Preparations

The voltammetric behaviour of cyproterone acetate (CPA) was studied using direct current (DCt) and differential pulse polarography (DPP). The drug manifests cathodic waves over the pH range of 4-11.8. In Britton-Robinson buffer (BRb) of pH 10, the diffusion current-concentration relationship was found to be rectilinear over the range 3.2-32 μg/mL and 0.5-14 μg/mL using DCt and DPP modes, respectively, with minimum limits of detection (LOD) of 0.13 μg/mL using the DDP. The diffusion-current constant (Id) was 9.29 ± 0.046 (n=9). The proposed method was successfully applied to the determination of the studied compound in its formulations. The mean percentage recoveries in tablets were 99.48 ± 1.25 and 100.01 ± 1.07 (n = 4) using DCt and DPP modes, respectively. The results obtained were in agreement with those of the reference method. A proposal for the electrode reaction was postulated.