title: Enhancement of Tb3+ fluoresence induced by serum proteins other than apotransferrin.
abstract: When Tb3+ ions are incubated with human serum, there is a large enhancement in the fluorescence of the Tb3+ ions as revealed by the excitation and emission wavelength pair 288 and 545 nm. The fluorescence enhancement represents the binding of Tb3+ ions not only to (apo)transferrin, but to albumin and gamma-globulins as well. Spectrophotometric evidence indicate involvement of tyrosyl residues at the cation binding site(s). The ion fluorescence induced by albumin and gamma-globulins invalidates the usefulness of the fluorometric determination of transferrin in the routine laboratory.
mesh_terms: D001059:Apoproteins; D001665:Binding Sites; D001798:Blood Proteins; D055598:Chemical Phenomena; D002621:Chemistry; D006801:Humans; D012709:Serum Albumin; D013050:Spectrometry, Fluorescence; D013725:Terbium / Q000097:blood*; D014168:Transferrin; D005719:gamma-Globulins
chemical_list: D001059:Apoproteins; D001798:Blood Proteins; D012709:Serum Albumin; D014168:Transferrin; D005719:gamma-Globulins; D013725:Terbium