ELECTROCHEMICAL BEHAVIOR AND DIFFERENTIAL PULSE VOLTAMMETRIC DETREMINATION OF CEFTAZIDIME, CEFUROXIME-AXETIL AND CEFTRIAXONE

Abstract

The voltammetric behavior of ceftazidime, cefuroxime-axetil and ceftriaxone has been examined in pH range 2.0-8.0 by cyclic and differential pulse voltammetry using hanging mercury drop electrode. The effect of the pH and scan rate on the peak currents and potentials was examined. The nature of the electrode reduction process in acid solution was found to be diffusion controlled for ceftazidime and cefuroxime-axetil, but strongly influenced by the adsorption in the case of ceftriaxone reduction. Ceftriaxone adsorption decreased with the increase of pH, and at pH>7 the reduction process became diffusion controlled. Based on this study, DPV method was developed, validated and suggested for determination of ceftazidime at pH 2.0, cefuroxime-axetil at pH 3.5 and for ceftriaxone at pH 8.0. Linear concentration ranges, LOD and LOQ were determined. The method was applied for determination of cephalosporins in pharmaceutical dosage forms: Ceftazidime powder, Ceroxim tablets and Longaceph powder for injection solution.