Voltammetric determination of ofloxacin by using a laser-modified carbon glassy electrode.

Abstract

A novel electrochemical sensor is described for the determination of ofloxacin (OFL) in environmental water samples. A laser-modified glassy carbon electrode (LGCE) was structured and characterized by scanning electron microscopy, atomic force microscopy, X-ray diffraction, X-ray photoelectron spectroscopy, and electrochemical impedance spectroscopy. The increase in electrochemical activity is due to a moderate increase in the surface roughness and to the presence of functional groups on the LGCE. Under optimal conditions (viz. a pH value of 5.5, a laser power of 1.8W and an action time of 40s), the sensor is capable of detecting OFL by differential pulse voltammetry at aworking potential of +0.91V (versus Ag/AgCl). Response is linear from 0.25 to 200μM for OFL concentration range, and the detection limit is 75nM (at S/N = 3). Removal of oxygen from samples is not required. The sensor was successfully applied to the determination of OFL in spiked groundwater, tap water and wastewater samples, with apparent recoveries from 94.0 to 108.0% and a relative standard deviation of less than 4.8%." Graphical abstractSchematic representation of a method for determination of ofloxacin (OFL) by differential pulse voltammetry. It is making use of a laser modified glassy carbon electrode (LGCE), which increases the number ofactive functional groups andthe surface area compared to a conventionalGCE.