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A cellular screening assay using analysis of metal-modified fluorescence lifetime.

ABSTRACT: Current methods for screening cell receptor internalization often require complex image analysis with limited sensitivity. Here we describe a novel bioassay based on detection of changes in global fluorescence lifetime above a gold substrate, with superresolution axial sensitivity and no need for image analysis. We show that the lifetime of enhanced green fluorescent protein expressed in a cellular membrane is greatly reduced in close proximity to the gold, resulting in a distance-dependent lifetime distribution throughout the cell. We demonstrate the application of this phenomenon in a screening assay by comparing the efficacies of two small molecule inhibitors interfering with the internalization process of a G protein-coupled receptor.

SUBMITTER: Cade NI

PROVIDER: S-EPMC2877351 | biostudies-literature | 2010 Jun

REPOSITORIES: biostudies-literature

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A cellular screening assay using analysis of metal-modified fluorescence lifetime.

Cade Nicholas I NI Fruhwirth Gilbert G Archibald Stephen J SJ Ng Tony T Richards David D

Biophysical journal 20100601 11

Current methods for screening cell receptor internalization often require complex image analysis with limited sensitivity. Here we describe a novel bioassay based on detection of changes in global fluorescence lifetime above a gold substrate, with superresolution axial sensitivity and no need for image analysis. We show that the lifetime of enhanced green fluorescent protein expressed in a cellular membrane is greatly reduced in close proximity to the gold, resulting in a distance-dependent life ...[more]

PMID: 20513420

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