Photodegradation of ciprofloxacin and ofloxacin antibiotics and their photo-metabolites with sunlight

In this study, nano graphene oxide magnetite (Nano-GO/M) composite was prepared and characterized under laboratory conditions with FTIR and SEM analysis to investigate the metabolites of ciprofloxacin (CIP) and ofloxacin (OFL) antibiotics formed during photooxidation under sunlight. Two different metabolites of CIP and OFL namely desenthylenciprofloxacin (M1) and oxociprofloxacin (M3); and 9-piperazino ofloxacin (POF) and des-methyl ofloxacin (MOF) were in HPLC. For maximum removal efficiency (80%) of 1 mg/L initial CIP concentration, 250 min irradiation time were obtained as optimum time for photo-oxidation via sunlight irradiation at 80 W power in august at hours between 10.00 am and 17.00 pm (for 24 hours experiments, we keep going at these hours for 4.5 days). Best results were obtained at 1 mg/L initial concentration of CIP, at original pH of CIP solutions (6.5) and at 2 g/L Nano-GO/M concentration. For maximum OFL removal (82%) the optimum Nano-GO/M concentration was found to be 2 g/L at 1 mg/L OFL concentration, at pH 6.5, after 350 min irradiation time, at 35C 5C. Final concentrations of M1, M3, POF and MOF metabolites were found as 0.425, 0.125, 0.098 and 0.075 mg/L, respectively.