The Photolytic Production of Chromophores and Fluorescence in Wool Keratin

The differential reflectance and three-dimensional fluorescence spectra of wet and dry wool following UVB irradiation at 303 nm in the presence and absence of oxygen were measured. Fluorescence originating from tryptophan residues was reduced under all irradiation conditions and a non-fluorescent chromophore with a maximum at 320 nm was produced. These findings suggest that neither singlet oxygen nor triplet states are involved in the formation of the chromophore