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Responsive Fluorophore Aggregation Provides Spectral Contrast for Fluorescence Lifetime Imaging.

ABSTRACT: Fluorophores experience altered emission lifetimes when incorporated into and liberated from macromolecules or molecular aggregates; this trend suggests the potential for a fluorescent, responsive probe capable of undergoing self-assembly and aggregation and consequently altering the lifetime of its fluorescent moiety to provide contrast between the active and inactive probes. We developed a cyanobenzothioazole-fluorescein conjugate (1), and spectroscopically examined the lifetime changes caused by its reduction-induced aggregation in vitro. A decrease in lifetime was observed for compound 1 in a buffered system activated by the biological reducing agent glutathione, thus suggesting a possible approach for designing responsive self-aggregating lifetime imaging probes.

SUBMITTER: Schleyer KA

PROVIDER: S-EPMC8247454 | biostudies-literature | 2020 Aug

REPOSITORIES: biostudies-literature

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Responsive Fluorophore Aggregation Provides Spectral Contrast for Fluorescence Lifetime Imaging.

Schleyer Kelton A KA Datko Benjamin D BD Burnside Brandon B Cui Chao C Ma Xiaowei X Grey John K JK Cui Lina L

Chembiochem : a European journal of chemical biology 20200416 15

Fluorophores experience altered emission lifetimes when incorporated into and liberated from macromolecules or molecular aggregates; this trend suggests the potential for a fluorescent, responsive probe capable of undergoing self-assembly and aggregation and consequently altering the lifetime of its fluorescent moiety to provide contrast between the active and inactive probes. We developed a cyanobenzothioazole-fluorescein conjugate (1), and spectroscopically examined the lifetime changes caused ...[more]

PMID: 32180309

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