A reversed phase ion-pair high-performance liquid chromatography assay has been developed for the determination of amphotericin B (AmB) in aqueous media. This assay has been applied to a factorial stability study of AmB. The effects of temperature, pH, ionic strength, surfactant concentration, oxygen and light on AmB have been investigated using a 25 × 3 factorial design. Results indicate that oxygen, light and temperature have significant effects on the stability of AmB solutions. Interactions between temperature and ionic strength, ionic strength and surfactant, pH and temperature and surfactant have also been identified. It is concluded that AmB is most stable in the absence of light, in oxygen-free environment and at low temperatures.
