Ultrafast dynamics of lumichrome in solution and in chemical and biological caging media

► Slower hydrogen-bonding dynamics in methanol revealed by 2-6 ps rise time. ► Low restrictions for bulk solvent to interact with guest in β-CD complexes. ► Larger protection of caged guest within protein pocket. ► Non-emitting state in Lc/HSA suggested due to electron transfer. ► Increased efficiency of ISC process in Lc/β-CD in comparison with water.