Effect of storage time on microwave saturation of EPR spectra of thermally sterilized streptomycin and its practical applications

Electron paramagnetic resonance spectroscopy at X-band (9.3 GHz) is used as the tool of optimalization of storage of thermally sterilized aminoglycoside antibiotic - streptomycin. Thermal sterilization at different conditions was performed according to the norms. Changes in free radicals system of this drug during storage after sterilization were detected. Lineshape analysis and microwave saturation of EPR spectra were done. Free radical concentrations were determined. Microwave saturation EPR analysis is proposed as useful method to determine the best conditions of storage of sterilized drugs.