RESUMO
The current effort introduces a facile construction of peony-like CuO:Tb3+ nanostructure (P-L CuO:Tb3+ NS), whose characterization was determined via techniques of X-ray diffraction, scanning electron microscopy and energy dispersive X-ray spectroscopy. We investigated ofloxacin, pefloxacin and gatifloxacin oxidation electrochemically on P-L CuO:Tb3+ NS-modified glassy carbon electrode (P-L CuO:Tb3+ NS/GCE), the results of which revealed the irreversible oxidation of drugs through a two-electron oxidation process. An admirable resolution was found for this modified electrode between voltammetric peaks of ofloxacin, pefloxacin and gatifloxacin, suggesting its appropriateness for simultaneous detection of these drugs in pharmaceutical media. In addition, our nanostructure synergistically influenced the electro-catalytic oxidations of these three compounds. Differential pulse voltammetric measurements of ofloxacin, pefloxacin and gatifloxacin through our sensor showed a limit of detection of 1.9, 2.3 and 1.2 nM a as well as a linear dynamic range between 0.01 and 800.0 µM in phosphate buffered solution (0.1 M, pH = 6.0), respectively. Moreover, as-fabricated sensor could successfully co-detect these drugs in real serum and tablets specimens. In addition, since we use animal foods such as milk it is very important to detect their fluoroquinolone residues. For this purpose, the proposed sensor was tested to determine the residues of ofloxacin, pefloxacin and gatifloxacin in milk.
