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Reversible Aptamer-Au Plasmon Rulers for Secreted Single Molecules.

ABSTRACT: Plasmon rulers, consisting of pairs of gold nanoparticles, allow single-molecule analysis without photobleaching or blinking; however, current plasmon rulers are irreversible, restricting detection to only single events. Here, we present a reversible plasmon ruler, comprised of coupled gold nanoparticles linked by a single aptamer, capable of binding individual secreted molecules with high specificity. We show that the binding of target secreted molecules to the reversible plasmon ruler is characterized by single-molecule sensitivity, high specificity, and reversibility. Such reversible plasmon rulers should enable dynamic and adaptive live-cell measurement of secreted single molecules in their local microenvironment.

SUBMITTER: Lee SE

PROVIDER: S-EPMC4545488 | biostudies-literature | 2015 Jul

REPOSITORIES: biostudies-literature

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