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.
Dubertret
B
B
Center for Studies in Physics and Biology, The Rockefeller University, 1230 York Avenue, New York, NY 10021, USA. benoit@pollux.rockefeller.edu
Calame
M
M
Libchaber
A J
AJ
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