The fluorescence decay analysis of intramolecular two-state excited-state processes with added quencher is discussed in terms of compartments. The kinetic equations specifying the fluorescence decay and the time-course of the two excited-state species concentrations are expressed in terms of the rate constants and the spectroscopic parameters b₁ and c₁. b₁ and c₁ are respectively the relative absorbance and the normalized spectral emission weighting factor of species 1. The report investigates what has to be known beforehand to determine all relevant parameters. The results of this identifiability study indicate that the following conditions have to be satisfied in order to make an intramolecular two-state excited-state system with added quencher identifiable. First, at least three different quencher concentrations must be used. Second, the two rate constants of quenching must be different. Third, at least one parameter must be known. This parameter can be (1) one rate constant which is not a rate constant of quenching, (2) one b₁ value or, (3) one c₁ value. In each of these cases an alternative set of system parameters is mathematically possible. A unique solution is guaranteed when the fluorescence decays of a quenched model compound are included in the compartmental analysis.

Date Published: 1 April 1992
PDF: 12 pages
Proc. SPIE 1640, Time-Resolved Laser Spectroscopy in Biochemistry III, (1 April 1992); doi: 10.1117/12.58226

Published in SPIE Proceedings Vol. 1640:
Time-Resolved Laser Spectroscopy in Biochemistry III
Joseph R. Lakowicz, Editor(s)