RESUMO
The chemical stability of 2',3'-dideoxyinosine has been studied over a wide pH range (0-12). A stability-indicating HPLC method was used to separate the degradation product from the parent drug. The effects of temperature, ionic strength and buffer components on the degradation kinetics were investigated. Furthermore, the influence of some cyclodextrins (alpha-, beta-, HP-beta-, DM-beta- and gamma-cyclodextrin) on the drug stability have been studied.
Assuntos
Ciclodextrinas/química , Didanosina/química , Soluções Tampão , Cromatografia Líquida de Alta Pressão , Estabilidade de Medicamentos , Concentração de Íons de Hidrogênio , Cinética , Concentração Osmolar , TemperaturaRESUMO
The effects of cyclodextrins on the chemical stability of several mitomycin antibiotics in an alkaline medium have been investigated. A stability-indicating high-performance liquid chromatographic method was used to determine the overall degradation rate constants. The influence of various parameters such as structural variations of the cyclodextrins and mitomycins, temperature and pH was studied. It appears that complexation is most favourable with gamma-cyclodextrin. All mitomycin-gamma-cyclodextrin complexes degrade at lower rates than those of the free drugs. Moreover, it was shown that gamma-cyclodextrin influences the equilibrium between mitomycin C and its zwitterion mesomer.