ISSN:
1573-4994
Keywords:
Fluorescence quenching
;
transient effect
;
Smoluchowski–Collins–Kimball model
;
numerical simulation
Source:
Springer Online Journal Archives 1860-2000
Topics:
Physics
Notes:
Abstract Numerical simulations designed to illuminate the opportunities for and limitations on recovering the parameters in the Smoluchowski–Collins–Kimball (SCK) model of time-dependent fluorescence quenching from the data of time-correlated single-photon counting experiments have been carried out. Two “donors” with lifetimes of 880 and 410 ps, corresponding to the unquenched S2 lifetimes of 2,2,3,3-tetramethylindanethione (TMIT) and 9,9-dimethylanthrathione (DMAT) in inert perfluoroalkane solvents at room temperature, were used for purposes of illustration. The failure of the single-exponential decay model due to the transient effect can be detected at lower quencher concentrations for longer-lived fluorophores. While good values of the diffusion coefficient, effective encounter distance, and scaling parameters can be recovered at sufficiently high quencher concentrations, the simulations show that values of the specific rate constant, κ, can be expected to vary by up to two orders of magnitude when it is recovered from typical time-correlated single-photon counting data even if the data can be reliably described by the SCK model. The ability to differentiate between SCK kinetics and single-exponential kinetics by using fluorophores of varying unquenched lifetimes has also been explored.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1023/A:1022565902613
Permalink
