Electrochemical Sensor Using Glassy Carbon Electrode Modified with HPMαFP/Ppy/GCE Composite Film for Determination of Ofloxacin

Abstract

In this work, an electrochemical sensor HPMαFP / Ppy /GCE (HPMaFP: 1-phenyl-3-methyl-4-(2-furoyl)-5-pyrazolone, Ppy: polypyrrole, GCE: glassy carbon electrode) was prepared for the determination of ofloxacin (OFL: (+-)-9-Fluoro-2,3-dihydro-3-methyl-10-(4-methyl-1-piperazinyl)-7-oxo-7H-pyrido(1,2,3-de)-1,4-benzoxazine-6-carboxylic acid). The electrochemical parameters of ofloxacin were investigatigated by cyclic voltammetry and differential pulse voltammetry. In pH=7.0 phosphate buffer solution, one sensitive oxidation peak of OFL with Ep=0.88V is obtained on the electrochemical sensor. The difference of peak potential(△Ep) was 70mV lower than which on bare glassy carbon electrode, and the potential of ofloxacin moved negatively slightly which on Ppy modified electrode.Compared to the bare GCE and Ppy /GCE, the electrochemical sensor showed an excellent electrocatalytic effect on the oxidation of ofloxacin and displayed a shift of the oxidation potential in the negative direction with significant increase in the peak current. Under the optimumed condition in voltammetric method, the concentration calibration range and detection limit are 2×10-6~1×10-4 mol/L and 6.5×10-8 mol/L for OFL. This developed method had been applied to the direct determination of OFL in ophthalmic solution samples.