Light-controlled molecular switches modulate nanocrystal fluorescence.

Linyong Zhu; Ming-Qiang Zhu; James K Hurst; Alexander D Q Li

doi:10.1021/ja0423421

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PubMed · 15969571

Light-controlled molecular switches modulate nanocrystal fluorescence.

Linyong Zhu·Ming-Qiang Zhu·James K Hurst·Alexander D Q Li

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Abstract

Spiropyran dyes were attached to fluorescent core-shell CdSe/ZnS nanocrystals via thiol-containing linkers. Photoisomerization of the dye to its merocyanine form by UV irradiation caused a dramatic loss in the intrinsic nanoparticle fluorescence, which was regained upon reversing the isomerization with visible light. The fluorescence quenching efficiency increased with increasing spectral overlap of fluorescence emission and merocyanine adsorption bands, consistent with FRET as the quenching mechanism. Typically, complete quenching required at least 80 bound dye molecules per particle.

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Benzopyrans Cadmium Compounds Crystallization Fluorescent Dyes Indoles Molecular Structure Nanostructures Nitro Compounds Selenium Compounds Sulfides Time Factors Ultraviolet Rays Zinc Compounds Journal Article Research Support, N.I.H., Extramural Research Support, U.S. Gov't, Non-P.H.S.Research Support, U.S. Gov't, P.H.S.

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Linyong Zhu, Ming-Qiang Zhu, James K Hurst, Alexander D Q Li. 2005-06-29. Light-controlled molecular switches modulate nanocrystal fluorescence.. https://doi.org/10.1021/ja0423421

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