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Quantum-dot/aptamer-based ultrasensitive multi-analyte electrochemical biosensor.

Jacob A Hansen·Joseph Wang·Abdel-Nasser Kawde·Yun Xiang·Kurt V Gothelf·Greg Collins
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Abstract

The coupling of aptamers with the coding and amplification features of inorganic nanocrystals is shown for the first time to offer a highly sensitive and selective simultaneous bioelectronic detection of several protein targets. This is accomplished in a single-step displacement assay in connection to a self-assembled monolayer of several thiolated aptamers conjugated to proteins carrying different inorganic nanocrystals. Electrochemical stripping detection of the nondisplaced nanocrystal tracers results in a remarkably low (attomole) detection limit, that is, significantly lower than those of existing aptamer biosensors. The new device offers great promise for measuring a large panel of disease markers present at ultralow levels during early stages of the disease progress.

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Aptamers, PeptideBiosensing TechniquesCadmium CompoundsElectrochemistryLeadModels, MolecularNanostructuresProteinsQuantum DotsSensitivity and SpecificitySulfidesJournal ArticleResearch Support, N.I.H., ExtramuralResearch Support, U.S. Gov't, Non-P.H.S.

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Jacob A Hansen, Joseph Wang, Abdel-Nasser Kawde, Yun Xiang, Kurt V Gothelf, Greg Collins. 2006-02-22. Quantum-dot/aptamer-based ultrasensitive multi-analyte electrochemical biosensor.. https://doi.org/10.1021/ja060005h

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