Linescan microscopy data to extract diffusion coefficient of a fluorescent species using a commercial confocal microscope

Abstract

We report here on the measurement of the diffusion coefficient of fluorescent species using a commercial microscope possessing a resonant scanner. Sequential linescans with a rate of up to 12 kHz yield a temporal resolution of 83 μs, making the setup amenable to measure diffusion rates over a range covering at least three orders of magnitude, from 100 μm2/s down to 0.1 μm2/s. We share representative data sets covering (i) the diffusion of a dye molecule, observed in media of different viscosities and (ii) the diffusion of a prototypical membrane receptor.The data can be valuable for researchers interested in the rapid diffusion properties of nuclear, cytosolic or membrane bound proteins fused to fluorescent tags. Keywords: Confocal microscopy, Fluorescence correlation spectroscopy, Membrane receptor, Diffusion