Development of a New Coated Platinum Selective Electrode for Moxifloxacin Determination

The construction of a new moxifloxacin (MOX) hydrochloride coated platinum selective electrode based on MOX-tetraphenylborate (MOX-TPB) as electroactive material is described. Plasticized polymeric membranes with a composition of polyvinyl chloride. o-nitrophenyl pentyl ether: MOX-TPB:potassium tetrakis(4-chlorophenyl) borate in the percentage ratio of 30:66:2:2 (%, w:w:w) were selected. The sensor displayed rapid, stable and near-Nernstian response, 57.6 ± 0.6 mV · decade^-1, over the concentration range of 2 × 10^-6 to 1 × 10^-2 mol · L^-1. The pH does not affect the performances of the proposed electrode within the pH range 3-5.5. The electrode is proved to have a good selectivity for MOX hydrochloride over some inorganic and organic compounds. The constructed electrode was proved to be successful for the potentiometric titration of MOX cation with TPB solution in raw material and in reconstituted powders containing MOX. The results were validated by comparison with a capillary electrophoresis method.