Detection of antibiotic Ofloxacin drug in urine using electrochemical sensor based on synergistic effect of different morphological carbon materials

The Ofloxacin drug is used for the treatment of bacterial infections that cause bronchitis, pneumonia, chlamydia, gonorrhea, skin infections, urinary tract infections, and infections of the prostate. The trace determination of Ofloxacin is very important for minimizing the risks of human intoxication and prevents serious environmental impacts. In this study, a new sensor was prepared by a carbon paste electrode blended with flake graphite and oxidized multiwall carbon nanotubes. The resistance of the modifier materials measured by 4-point probe system and results are about 48.8, 5.2, and 1726 m Omega for the powder graphite, flake graphite, and oxidized multiwall carbon nanotubes, respectively. On the blended sensor, the electric conductivity and electro-catalytic activity towards the electrochemical oxidation of Ofloxacin are better than those of carbon paste electrodes modified with flake graphite or oxidized multiwall carbon nanotube. Under optimal conditions, the modified carbon paste electrode successfully achieved detection limits of 0.18 nmol.L-1, and 0.24 nmol.L-1 in pharmaceutical and in spiked human urine samples, respectively. The sensor is highly stable, reusable, and free of interference from other commonly present excipients in drug formulations.