Journal
APPLIED SPECTROSCOPY
Volume 55, Issue 3, Pages 311-317Publisher
SOC APPLIED SPECTROSCOPY
DOI: 10.1366/0003702011951713
Keywords
fluorescence polarization anisotropy; fluorescence correlation spectroscopy; two-photon excitation; multifrequency phase fluorometer
Categories
Ask authors/readers for more resources
We report here the phase-sensitive measurements of two-photon fluorescence polarization anisotropy (FPA) on highly diluted solutions. We first describe the characterization of the response of the two-photon microscope to the light polarization and its test by means of measurements of the FPA on rhodamine 6G as a function of the viscosity, Further, we report the study of the FPA at high dilutions on a globular protein, the beta-lactoglobulin B (BLG) labeled with Alexa 532, The number of molecules (from 0.4 to 17 molecules per excitation volume) is measured by means of fluorescence correlation spectroscopy (FCS), The average rotational and translational diffusion coefficients measured with the FPA and FCS methods are in good agreement with the protein size and do not show a substantial dependence on the protein concentration, despite the very low signal (congruent to3 times the background) observed for highly diluted solutions.
Authors
I am an author on this paper
Click your name to claim this paper and add it to your profile.
Reviews
Recommended
No Data Available