Fig 1. Measurement of anti-oxidative effects of LVFX using EPR spectroscopy.

The scavenging activities of LVFX against ROS derived from the UV/H₂O₂ system or neutrophils stimulated with 100 ng/ml PMA were determined using ESR spin trapping with DMPO. (A) The reaction mixtures, which contained 500 μM H₂O₂, 100 μM DTPA and 4.5 mM DMPO, were incubated with each FQ and were immediately transferred to an ESR flat cell and irradiated at 254 nm for 30 s. After UV-irradiation, the ESR flat cells immediately placed in a JES-TE 200 ESR spectrometer. ESR spectrum of DMPO spin adducts of OH radicals and (B) the quantitation of the OH radicals concentration were shown. (C) The scavenging activity of 200 μM FQs; lomefloxacin (LFLX), levofloxacin (LVFX), Ciprofloxacin (CPFX), pazfloxacin (PZFX), and norfloxacin (NRFX) against OH radicals. (D) ESR spectrum of DMPO spin adducts ROS derived from neutrophils containing OH radicals, and (E) the quantitation of the ROS concentration were shown. Each bar represents the mean ± SD (n = 3). *p<0.05, **p<0.01 vs control.