Photostability of triazole antifungal drugs in the solid state

The publication is devoted to photostability assessment of four triazole antifungal drugs: fluconazole, itraconazole, posaconazole and voriconazole. The compounds were exposed in the solid state using the whole spectrum of UV-Vis radiation. The analyses were performed using high performance thin layer chromatography (HPTLC) technique with densitometric detection. The results indicates considerable degradation of structurally similar itraconazole and posaconazole which could be clinically significant. After 72 hours of itraconazole irradiation there remain less than 25%, and 60% in case of posaconazole. To a lesser extent photodegradation concern two other compounds with a separate chemical structure: fluconazole and voriconazole. After 72 hours of irradiation there left 75% and 82% of these substances, respectively. The strict dependence between compound photostability and its chemical structure was observed.