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PubMed · 15783528

Short-range spectroscopic ruler based on a single-molecule optical switch.

Mark Bates·Timothy R Blosser·Xiaowei Zhuang
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Abstract

We demonstrate a novel all-optical switch consisting of two molecules: a primary fluorophore (Cy5) that can be switched between a fluorescent and a dark state by light of different wavelengths, and a secondary chromophore (Cy3) that facilitates switching. The interaction between the two molecules exhibits a distance dependence much steeper than that of conventional Fo rster resonance energy transfer. This enables the switch to act as a ruler with the capability to probe distances difficult to access by other spectroscopic methods, thus presenting a new tool for the study of biomolecules at the single-molecule level.

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Bacterial ProteinsBiotinCarbocyaninesDNADNA DamageFluorescence Resonance Energy TransferModels, MolecularOptics and PhotonicsRNA, CatalyticSerum Albumin, BovineJournal ArticleResearch Support, Non-U.S. Gov'tResearch Support, U.S. Gov't, Non-P.H.S.

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Mark Bates, Timothy R Blosser, Xiaowei Zhuang. 2005-03-15. Short-range spectroscopic ruler based on a single-molecule optical switch.. https://doi.org/10.1103/physrevlett.94.108101

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