[Simultaneous determination of ciprofloxacin and flumequine in water samples by high performance liquid...

In order to meet the field sample measurements and laboratory research, a simple, stable, and popular high performance liquid chromatographic (HPLC) method was established for the determination of the concentrations of two fluoroquinolone antibiotics in water samples simultaneously and rapidly. Thus, it could provide valuable information for other scholars to study the interactions between different antibiotics. Ciprofloxacin (CIP) and flumequine (FLU) were taken as the target contaminants because of their wide application in medical career. Furthermore, this study also investigated the different types of mobile phase, different mobile phase ratios, common ions (Ca2+, Mg2+, Fe3+, Al3+, SO4(2-) and HCO3(-)) in water samples and other factors on CIP and FLU measurements with this method. The results showed that triethylamine has obvious effect on improving column efficiency. Low concentrations of ions had little effect on the test, but Fe3+ and Al3+ might cause baseline instability, because Fe3+ and Al3+ may form complexes with the surface hydroxyl groups of the stationary phase or the test components. The results may be referred by other workers for the optimization of the determination conditions.