RESUMO
Degradation of penicillin in acidic media (pH 2.7) was monitored by high-pressure liquid chromatography and UV spectroscopy. The effects of temperature, buffer concentration, and ionic strength were examined. A degradation pathway is proposed, and the apparent first-order rate constant and energy of activation were calculated for each reaction. One or more degradation products containing a sulfhydryl group, a functional group often suggested as having a major role in eliciting allergic responses to penicillin therapy, were present throughout the degradation scheme.
Assuntos
Penicilinas , Ácidos , Soluções Tampão , Catálise , Fenômenos Químicos , Química , Cromatografia Líquida de Alta Pressão , Estabilidade de Medicamentos , Cinética , Concentração Osmolar , Penicilinas/análise , TemperaturaRESUMO
An anion-exchange high-pressure liquid chromatographic system capable of separating penicillin G potassium from five of its degradation products was developed. The retention times were: penicillin G potassium, 17.5 min; DL-penicillamine, 4.5 min; benzylpenilloic acid, 7.0 and 8.0 min; benzylpenamaldic acid, 13.0 min; benzylpenicilloic acid, 19.5 min; and benzylpenillic acid, 22.0 min. In addition, the system permits quantification using linear calibration curves.
