Single-mismatch detection using gold-quenched fluorescent oligonucleotides.

B Dubertret; M Calame; A J Libchaber

doi:10.1038/86762

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Single-mismatch detection using gold-quenched fluorescent oligonucleotides.

B Dubertret·M Calame·A J Libchaber

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Abstract

Here we describe a hybrid material composed of a single-stranded DNA (ssDNA) molecule, a 1.4 nm diameter gold nanoparticle, and a fluorophore that is highly quenched by the nanoparticle through a distance-dependent process. The fluorescence of this hybrid molecule increases by a factor of as much as several thousand as it binds to a complementary ssDNA. We show that this composite molecule is a different type of molecular beacon with a sensitivity enhanced up to 100-fold. In competitive hybridization assays, the ability to detect single mismatch is eightfold greater with this probe than with other molecular beacons.

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Base Pair Mismatch Base Sequence Binding, Competitive DNA, Single-Stranded Dose-Response Relationship, Drug Fluorescent Dyes Genetic Techniques Gold Molecular Sequence Data Nucleic Acid Hybridization Oligonucleotides Protein Binding Protein Conformation Time Factors Journal Article Research Support, Non-U.S. Gov't

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B Dubertret, M Calame, A J Libchaber. 2001. Single-mismatch detection using gold-quenched fluorescent oligonucleotides.. https://doi.org/10.1038/86762

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