Solvent effects on the spectroscopic properties of aflatoxin B1.
1. Solvent-induced changes in the spectral properties of aflatoxin B1 were investigated using protic and aprotic solvents. 2. The absorption data were less sensitive to solvent effects than the fluorescence emission data. 3. Stokes shifts in protic solvents were greater than those in aprotic solvents indicating hydrogen bond formation between solvent and the excited state of aflatoxin B1. 4. From the Stokes shift data for aprotic solvents, the dipole moment of aflatoxin B1 was estimated to increase by 15.7 Debye units upon excitation to the excited singlet state.