Multi-Photon
Fluorescence Correlation Spectroscopy (FCS)
Investigators:
Serge Pelet, Mike Previte, Peter So
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Fluorescence
correlation spectroscopy (FCS) has been employed to study translational
and rotational diffusion, chemical reactions, single molecule detection,
flow and other biochemical processes. With the recent development
of dual-color FCS, it is now possible analyze the dynamics of bi-molecular
association processes, such as nucleic acid strand annealing, antibody-antigen
interactions, or ligand-receptor binding (1). |
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Figure
1: |
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Presently, the sensitivity
of two-color FCS systems is limited by spectral bleedthrough or
crosstalk in individual detection channels. Thus, there exists a
lower detection limit for two-color labeled association product.
We are developing multi-spectral multi-photon FCS based on single
photon counting multi-anode-PMT systems. Spectral resolved detection
allows the elimination of bleed-through error based on numerical
decomposition.
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Schwille,
P. et al. Biophys. J. 66:211, 1997 |
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ain body}------------------------------------[ |
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