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Reversible energy-transfer switching on a DNA scaffold.

ABSTRACT: We show that FRET between Pacific Blue (PB) and Alexa488 (A488) covalently attached to a DNA scaffold can be reversibly controlled by photochromic switching of a spiropyran derivative. With the spiropyran in the closed spiro isomeric form, FRET occurs freely between PB and A488. UV-induced isomerization to the open merocyanine form shuts down the FRET process by efficient quenching of the PB excited state. The process is reversed by exposure to visible light, triggering the isomerization to the spiro isomer.

SUBMITTER: Balter M

PROVIDER: S-EPMC4353014 | biostudies-literature | 2015 Feb

REPOSITORIES: biostudies-literature

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Reversible energy-transfer switching on a DNA scaffold.

Bälter Magnus M Hammarson Martin M Remón Patricia P Li Shiming S Gale Nittaya N Brown Tom T Andréasson Joakim J

Journal of the American Chemical Society 20150217 7

We show that FRET between Pacific Blue (PB) and Alexa488 (A488) covalently attached to a DNA scaffold can be reversibly controlled by photochromic switching of a spiropyran derivative. With the spiropyran in the closed spiro isomeric form, FRET occurs freely between PB and A488. UV-induced isomerization to the open merocyanine form shuts down the FRET process by efficient quenching of the PB excited state. The process is reversed by exposure to visible light, triggering the isomerization to the ...[more]

PMID: 25687828

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