Sterility and Radiostability of Amoxicillin and Cefaclor Antibiotics Sterilized by Gamma Irradiation

Aim: The present investigations aimed at studying the effect of sterilization by gamma irradiation on amoxicillin and cefaclor antibiotics. They have been irradiated in solid dry state and the probable changes in physicochemical and microbiological properties were studied Place and Duration of Study: The study was carried out from 2011 to 2013 in the Drug Radiation Research Department, Egyptian Atomic Energy Authority. Methodology: Amoxicillin and cefaclor compounds in solid states were exposed to gamma irradiation in air atmosphere at room temperature, with a dose of 25kGy and afterwards they had been subjected to microbiological and analytical tests checking their sterility and antibacterial activitiy it was tested against different pathogenic bacterial species by measuring MIC using Microdilution technique and microplate reader. Then their chemical stability were evaluated by different techniques. EPR, FTIR, UV analysis, mass spectroscopy, and melting point. Results and conclusion: The results showed that the majority of initial unirradiated compounds had a slight degree contamination with Bacillus, Micrococcus genera, and fungi. By applying. irradiation at 25kGy it showed sterilization of the tested antibiotics and keeping their antibacterial activity. The EPR analysis results showed formation of free radicals. The other analytical tests (FTIR), (UV) analysis, mass spectroscopy, and melting point results proved that the antibiotics analyzed are radioresistant and can be sterilized by irradiation with a dose of 25kGy, without any detrimental effect on their properities and antibacterial activity.