Abstract
Newly developed coated wire electrodes have been developed for determination of cefditoren pivoxil (CTP) in pure form, pharmaceutical preparations and in biological fluids. The selective electrodes were fabricated based on the incorporation of cefditoren pivoxil with the ion exchangers, phosphomolybdic acid (CTP-PMA), phosphotungstic acid (CTP-PTA) and a mixture of both (CTP-PMA/PTA). The potential responses of the electrodes were influenced by the pH of tested solution. Under the condition of pH 5-10, the electrodes exhibit linear response over concentration range 1.0 x 10(-7) - 1.0 x 10(-2) mol/L with Nernstian slopes (56.29 +/- 0.09, 54.60 +/- 0.09 and 58.17 +/- 0.28 mV/decade at 25 degrees C) for the three electrodes, respectively. The influence of possible interfering species such as common inorganic cations, amino acids and different pharmacological related compounds was studied. The electrodes were successfully applied to determination of the drug in tablets by direct and standard addition potentiometry. Statistical student's t-test and F-test showed insignificant systematic error between proposed and reported methods.