Electrochemical Determination Research Of Ofloxacin In Water Environment

Ofloxacin(OFL),a typical fluorinated quinolone antibiotics,has been widely used in medical and veterinary fields.In recent years,more and more attention has been paid to it,since it was frequentlydetected in various environmental media.Therefore,it is very important to make a simple,rapid and sensitive electrochemical sensor to realize real-time and in situ detection of OFL in water environment.In this work,two kinds of modified electrodes were established by electrochemical method,which were designed to construct different electrochemical detection methods of OFL in water environment.The main results achieved are as follows:1.A sensitive and simple OFL sensor was successfully constructed withplatinum nanoparticles(PtNPs)/ graphene(Gr)hybrid films.The modified electrodes were characterized by scanning electron microscope(SEM),atomic force microscope(AFM),energy dispersive spectrometer(EDS)and cyclic voltammetry(CV).Various parameters such as concentration of graphene,pH and scan ratewere studied in the electrochemical process.The experimental results show that the linear response range of the sensor of0.75?10-6to 2.5?10-4mol L-1 and limit of detection(LOD)was 0.75?10-6 mol L-1under the optimized condition.The sensor was applied for the detection of OFL in groundwater and tap water.Therecoveries rangefrom 93.90% to 102.34%,and the relative standard deviation(R.S.D.)was less 2.83%.2.A laser modified glassy carbon electrode,with increased effective surface area of electrode and the amount and type of oxygen functional groups,was developed to enhance electrode surface activity for efficient detection ofOFL in water environment.The laser modified electrode was characterized by the SEM,(X-ray photoelectron spectroscopy)XPS and AFM measurements,and the mechanism of the improvement of electrode surface electrochemical activity was discussed.Under the optimal conditions,using the DPV technique,the laser modified electrode provided an analytical curve for ofloxacin in the range of 2.5?10-7-2?10-4mol L-1,and the limit of detection is 7.5?10-8mol L-1.The sensor was successfully applied for the OFL detection in groundwater and tap water,The recoveries range from 94%-108%,and the R.S.D.was less 4.80%.3.In this work,two kinds of electrochemical sensor were developed based onnovel nanometer materials and laser modification,respectively,with a wide linear range,low detection limit,and good stability and reproducibility.In addition,in the whole detection process,the system does not need to pass to remove O2,indicating that it is feasible to apply these two electrochemical detection method for the in situdetection of OFL in actual water environment.