Single-mismatch detection using gold-quenched fluorescent oligonucleotides.
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.
Center for Studies in Physics and Biology, The Rockefeller University, 1230 York Avenue, New York, NY 10021, USA. benoit@pollux.rockefeller.edu
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B
Dubertret
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Calame
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Libchaber
D020137:Base Pair Mismatch; D001483:Base Sequence; D001667:Binding, Competitive; D004277:DNA, Single-Stranded / Q000737:chemistry; D004305:Dose-Response Relationship, Drug; D005456:Fluorescent Dyes / Q000737:chemistry*; D005821:Genetic Techniques; D006046:Gold / Q000737:chemistry; D008969:Molecular Sequence Data; D009693:Nucleic Acid Hybridization; D009841:Oligonucleotides / Q000737:chemistry*; D011485:Protein Binding; D011487:Protein Conformation; D013997:Time Factors
D004277:DNA, Single-Stranded; D005456:Fluorescent Dyes; D009841:Oligonucleotides; D006046:Gold