Dataset Information

?FCS: multi-method global analysis enhances resolution and sensitivity in fluorescence fluctuation measurements.

ABSTRACT: Fluorescence fluctuation methods have become invaluable research tools for characterizing the molecular-level physical and chemical properties of complex systems, such as molecular concentrations, dynamics, and the stoichiometry of molecular interactions. However, information recovery via curve fitting analysis of fluctuation data is complicated by limited resolution and challenges associated with identifying accurate fit models. We introduce a new approach to fluorescence fluctuation spectroscopy that couples multi-modal fluorescence measurements with multi-modal global curve fitting analysis. This approach yields dramatically enhanced resolution and fitting model discrimination capabilities in fluctuation measurements. The resolution enhancement allows the concentration of a secondary species to be accurately measured even when it constitutes only a few percent of the molecules within a sample mixture, an important new capability that will allow accurate measurements of molecular concentrations and interaction stoichiometry of minor sample species that can be functionally important but difficult to measure experimentally. We demonstrate this capability using ?FCS, a new fluctuation method which uses simultaneous global analysis of fluorescence correlation spectroscopy and fluorescence lifetime data, and show that ?FCS can accurately recover the concentrations, diffusion coefficients, lifetimes, and molecular brightness values for a two component mixture over a wide range of relative concentrations.

SUBMITTER: Anthony NR

PROVIDER: S-EPMC3938748 | biostudies-literature | 2014

REPOSITORIES: biostudies-literature

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τFCS: multi-method global analysis enhances resolution and sensitivity in fluorescence fluctuation measurements.

Anthony Neil R NR Berland Keith M KM

PloS one 20140228 2

Fluorescence fluctuation methods have become invaluable research tools for characterizing the molecular-level physical and chemical properties of complex systems, such as molecular concentrations, dynamics, and the stoichiometry of molecular interactions. However, information recovery via curve fitting analysis of fluctuation data is complicated by limited resolution and challenges associated with identifying accurate fit models. We introduce a new approach to fluorescence fluctuation spectrosco ...[more]

PMID: 24587370

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Dataset Information

?FCS: multi-method global analysis enhances resolution and sensitivity in fluorescence fluctuation measurements.

Publications

τFCS: multi-method global analysis enhances resolution and sensitivity in fluorescence fluctuation measurements.

Similar Datasets

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