Interaction between Copper, Zinc Superoxide Dismutase and Quinolones

The interactions between quinolones (norfloxacin, ciprofloxacin, enoxacine) and copper, zinc superoxide dismutase (CuZnSOD) were investigated using absorption and fluorescence spectra. Quinolones can make CuZnSOD fluorescence quenching. The quenching mechanism is static quenching. The binding constants of quinolones with CuZnSOD were obtained at various temperatures. According to the Förster nonradiative energy transfer theory, the distance of donors and acceptors can be obtained. The main acting force between them is electrostatic gravitation. Quinolones can decrease the activity of CuZnSOD, and the activity of CuZnSOD in rabbits blood being injected with ciprofloxacin also decreased obviously. The results provide some references for clinical diagnosis using the activity level of CuZnSOD, which varies in patients with different diseases.