Purpose: Drug photodegradation is a matter of great concern because it can result in potency loss and adverse side effects. This study examines the light-induced degradation of dacarbazine catalyzed by vitamin B2 and flavin adenine dinucleotide (FAD) under light-emitting diode (LED) or fluorescent light irradiation.
Methods: Dacarbazine was irradiated with LED (405 nm) or fluorescent light in the presence of various equivalents of vitamin B2 or FAD. The photodegradation of the drug in D2O was monitored by 1H nuclear magnetic resonance spectroscopy.
Results: Dacarbazine dissolved in D2O decomposed in the presence of vitamin B2 or FAD under irradiation with LED or fluorescent light. The decomposition products were 2-azahypoxanthine 2, which has previously been observed after light irradiation in the absence of vitamin B2, and 1H-imidazole-5-carboxamide 6, a new product formed in the presence of vitamin B2. Irradiation with LED light was more effective than irradiation with fluorescent light in degrading dacarbazine.
Conclusion: Vitamin B2 and FAD induced dacarbazine photodegradation. Thus, the interfusion of vitamin B2 or FAD under excessive light exposure should be avoided during the intravenous administration of dacarbazine.
Keywords: dacarbazine; flavin adenine dinucleotide; photodegradation; riboflavin; vitamin B2.
© 2024. The Author(s).