An Alternate Solution of Fluorescence Recovery Kinetics after Spot-Bleaching for Measuring Diffusion Coefficients. 2. Diffusion of Fluorescein in Aqueous Sucrose Solutions

摘要

The traditional analysis of the fluorescence recovery kinetics after spot bleaching yields expressions for the diffusion coefficient of the probe that are not suitable for linear fittings. In a previous work we developed an improved recovery function that is a better alternative for data analysis. To illustrate its application to real cases and compare it with the previous data treatment, we measured the time response of fluorescein in aqueous sucrose solutions, covering the unsaturated and the supercooled region, where decoupling between diffusion and viscosity is observed. The results are compared with the mobility of different types of solutes in aqueous sucrose solutions and are discussed in terms of the classical hydrodynamic model.