Diffusion-influenced fluorescence quenching dynamics in one to three dimensions

The fluorescence decay curves obtained from diffusion-influenced quenching in various spatial dimensions are discussed. The two-dimensional quenching has, because of intractable fitting functions, previously been dealt with only in the completely diffusion-controlled case (corresponding to the Smoluchowski boundary condition). In this paper, an approximation for the two-dimensional (2D)-quenching behavior with the Collins-Kimball boundary condition is presented. The nonlinear least-squares method has been used to analyze simulated decay data. The consequences the choice of an incorrect model has on the final results as well as the possibility to discriminate between different dimensionalities are investigated. Also, some inherent properties of the fitting functions are studied.