Flow-Injection Amperometric Determination of Ceftriaxone, Cefotaxime, and Cefoperazone Using an Electrode Modified with a Binary System of Gold Particles and Mixed-Valent Ruthenium Oxides

Modified electrodes based on gold particles, mixed-valence ruthenium oxides, and a binary system combining these components were developed for the voltammetric determination of ceftriaxone, cefotaxime, and cefoperazone. The electrode with the binary system of gold particles and mixed-valence ruthenium oxides, which exhibited the best performance, was used for the detection of cephalosporins in flow-injection analysis. Optimal conditions for the detection of cephalosporins in a flow-injection system were selected. The dependence of the analytical signal on the concentration of the compounds under consideration is linear on logarithmic coordinates over the range from 5 x 10(-7) to 5 x 10(-3) M. The proposed procedure was tested in the determination of cephalosporins in pharmaceuticals.