Radiation sterilization of fluoroquinolones in solid state: investigation of effect of gamma radiation and electron beam.

The effect of gamma radiation from (60)Co source and 2MeV electron beam was studied on two fluoroquinolone antibiotics viz norfloxacin and gatifloxacin in the solid state. The changes in reflectance spectrum, yellowness index, vibrational characteristics, thermal behavior, UV spectrum, chemical potency (HPLC) and microbiological potency were investigated. ESR measurement gave the number of free radical species formed and their population.