Electron Spin Resonance (ESR) Investigation of Gamma-Irradiated Antibiotic Azithromycin

Abstract

The use of ionizing radiation for sterilization of pharmaceutical is now a well established technology. Electron spin resonance (ESR) spectroscopy was used to investigate the degradation Gamma- damage in the microcrystalline powder from antibiotic Azithroomycin (AZ) before and after exposure to 5 up to 25 KGy absorbed dose. ESR measurements proved various stable paramagnetic species after irradiation and relative yielding of free radicals depends on the absorbed gamma dose. The thermal behavior and their assignments of (AZ) were studies by using (DTA, TG) and Infra red. Some spectroscopic and thermal properties and suggestions concerning possible structure of the radicals are discussed in this paper.