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Updated: Jul 2, 2026

Measuring Diffusion Coefficients via Two-photon Fluorescence Recovery After Photobleaching
Published on: February 26, 2010
Photobleaching measurements of diffusion in cell membranes and aqueous cell compartments
1University of Pécs, Faculty of Medicine, Pécs, Hungary.
Abstract:
This commentary unit discusses in great detail the theoretical nature of fluorescence recovery after photobleaching (FRAP). This information is crucial to an understanding of how and why FRAP works in a cell system. Further, understanding how to interpret the data sets requires a sound knowledge of the processes involved. Of primary importance are the nature of membrane diffusion and the nature of the multiple compartments into which fluorescent dyes can enter. The unit provides a complete discussion of all aspects of FRAP from the perspective of cellular measurements.
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Fluorescent recovery after photobleaching (FRAP) is a fluorescent-protein-based detection technique used to quantify protein movement rates within the cell. This method exposes a small portion of the cell to an intense laser beam. The laser beam causes permanent photobleaching of the fluorophore-tagged proteins in the exposed region. As the bleached...

