1 February 1995 Time-resolved fluorescence study of interaction of the monoclonal anticoproporphyrin antibodies and (Pt-)coproporphyrin
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Proceedings Volume 2329, Optical and Imaging Techniques in Biomedicine; (1995) https://doi.org/10.1117/12.200906
Event: International Symposium on Biomedical Optics Europe '94, 1994, Lille, France
Abstract
Mechanisms of ligand binding by monoclonal anti-coproporphyrin antibodies are studied by steady-state and time-resolved fluorescence spectroscopy by use of a picosecond laser system. The antibodies quench the coproporphyrin (CP) fluorescence, but the CP fluorescence spectra show a strong shift of maxima at high concentrations of antibodies (Ab) or their Fab fragment. This can be explained by a special type of Ab or Fab dimerization. Fluorescence decays of CP are measured at different concentrations of Ab and different pH values. The following deconvolution procedure based on the non-linear least squares method reveals a two- exponential character of the fluorescence decay. Data obtained by polarized fluorescence spectroscopy allows us to attribute the slow component (16 ns) to the free CP and the fast one (2.5 ns) to the CP-Ab complex. The obtained dependence of the ratio of amplitudes of the fast and slow components on the ratio of concentrations of CP and Ab at different pH values makes it possible to register separately the binding at different centers within the Ab and investigation of the effects of cooperation in the Ab molecule. The following experiments with Pt-coproporphyrin reveal the ability of Ab to reduce quenching of long-lived phosphorescence of the ligand.
© (1995) COPYRIGHT Society of Photo-Optical Instrumentation Engineers (SPIE). Downloading of the abstract is permitted for personal use only.
Oleg I. Lobanov, Oleg I. Lobanov, Alexander P. Savitsky, Alexander P. Savitsky, Mary Nelen, Mary Nelen, Marina V. Demcheva, Marina V. Demcheva, Anatoly K. Yatsimirsky, Anatoly K. Yatsimirsky, Jouko E. Korppi-Tommola, Jouko E. Korppi-Tommola, } "Time-resolved fluorescence study of interaction of the monoclonal anticoproporphyrin antibodies and (Pt-)coproporphyrin", Proc. SPIE 2329, Optical and Imaging Techniques in Biomedicine, (1 February 1995); doi: 10.1117/12.200906; https://doi.org/10.1117/12.200906
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