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Phosphine quenching of cyanine dyes as a versatile tool for fluorescence microscopy.

ABSTRACT: We report that the cyanine dye Cy5 and several of its structural relatives are reversibly quenched by the phosphine tris(2-carboxyethyl)phosphine (TCEP). Using Cy5 as a model, we show that the quenching reaction occurs by 1,4-addition of the phosphine to the polymethine bridge of Cy5 to form a covalent adduct. Illumination with UV light dissociates the adduct and returns the dye to the fluorescent state. We demonstrate that TCEP quenching can be used for super-resolution imaging as well as for other applications, such as differentiating between molecules inside and outside the cell.

SUBMITTER: Vaughan JC

PROVIDER: S-EPMC3624894 | biostudies-literature | 2013 Jan

REPOSITORIES: biostudies-literature

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Phosphine quenching of cyanine dyes as a versatile tool for fluorescence microscopy.

Vaughan Joshua C JC Dempsey Graham T GT Sun Eileen E Zhuang Xiaowei X

Journal of the American Chemical Society 20130117 4

We report that the cyanine dye Cy5 and several of its structural relatives are reversibly quenched by the phosphine tris(2-carboxyethyl)phosphine (TCEP). Using Cy5 as a model, we show that the quenching reaction occurs by 1,4-addition of the phosphine to the polymethine bridge of Cy5 to form a covalent adduct. Illumination with UV light dissociates the adduct and returns the dye to the fluorescent state. We demonstrate that TCEP quenching can be used for super-resolution imaging as well as for o ...[more]

PMID: 23311875

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