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PubMed · 10733953

Two-dimensional fluorescence intensity distribution analysis: theory and applications.

P Kask·K Palo·N Fay·L Brand·U Mets·D Ullmann·J Jungmann·J Pschorr·K Gall
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Abstract

A method of sample analysis is presented which is based on fitting a joint distribution of photon count numbers. In experiments, fluorescence from a microscopic volume containing a fluctuating number of molecules is monitored by two detectors, using a confocal microscope. The two detectors may have different polarizational or spectral responses. Concentrations of fluorescent species together with two specific brightness values per species are determined. The two-dimensional fluorescence intensity distribution analysis (2D-FIDA), if used with a polarization cube, is a tool that is able to distinguish fluorescent species with different specific polarization ratios. As an example of polarization studies by 2D-FIDA, binding of 5'-(6-carboxytetramethylrhodamine) (TAMRA)-labeled theophylline to an anti-theophylline antibody has been studied. Alternatively, if two-color equipment is used, 2D-FIDA can determine concentrations and specific brightness values of fluorescent species corresponding to individual labels alone and their complex. As an example of two-color 2D-FIDA, binding of TAMRA-labeled somatostatin-14 to the human type-2 high-affinity somatostatin receptors present in stained vesicles has been studied. The presented method is unusually accurate among fluorescence fluctuation methods. It is well suited for monitoring a variety of molecular interactions, including receptors and ligands or antibodies and antigens.

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AlgorithmsAntigen-Antibody ReactionsBiophysical PhenomenaBiophysicsEvaluation Studies as TopicFluorescence PolarizationFluorescent DyesHumansMicroscopy, ConfocalMicroscopy, FluorescenceModels, TheoreticalPhotonsReceptors, SomatostatinRhodaminesSomatostatinTheophyllineJournal Article

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P Kask, K Palo, N Fay, L Brand, U Mets, D Ullmann, J Jungmann, J Pschorr, K Gall. 2000. Two-dimensional fluorescence intensity distribution analysis: theory and applications.. https://doi.org/10.1016/s0006-3495(00)76722-1

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