Electrochemical Determination of Sparfloxacin in Pharmaceutical Formulations and Urine Samples Using a β-Cyclodextrin Modified Carbon Paste Electrode

The electrochemical behavior of Sparfloxacin at β-cyclodextrin modified carbon paste electrode (CDMCPE) has been studied. Compared with bare carbon paste electrode (CPE), the β-cyclodextrin modified carbon paste electrode exhibited a marked enhancement of current response of Sparfloxacin. Cyclic voltammetric (CV) studies indicate that the process was irreversible and adsorption controlled. To obtain a good sensitivity, the instrumental and accumulation variables were studied using Differential Pulse Voltammetry (DPV). A linear calibration plot was obtained over the 0.043–60 μM range with a correlation coefficient of 0.999 in pH 3.0 Britton Robinson buffer with a detection limit of 0.04 μM by using DPV. The peaks from the techniques CV and DPV are attributed to the complex formation of quinone group of the drug with β-cyclodextrin. The repeatability and reproducibility of the methods were within 7.52, 7.68% RSD for peak currents and 0.52, 0.60% RSD for peak potentials using CDMCPE. Quantitative analysis was performed by the standard addition method for Sparfloxacin in both urine and available pharmaceutical formulations. A spectrophotometric method was used as a reference method to assess the accuracy. Results obtained through spectrophotometric method were comparable to those obtained by CDMCPE.