title: Hybridization-based unquenching of DNA hairpins on au surfaces: prototypical "molecular beacon" biosensors.
abstract: There is a keen interest in developing techniques for rapid genetic analysis that do not require labeling of an analyte. Here we demonstrate that fluorophore-tagged DNA hairpins attached to gold films can function as immobilized "molecular beacons". Two DNA hairpins incorporating portions of the Staphlococcus aureus FemA and mecR methicillin-resistance genes were attached to a gold substrate. Upon exposure to the complement, a approximately 26-fold increase in fluorescence intensity was measured corresponding to a 96 +/- 5% quenching efficiency. Studies with nonspecific DNA indicate that DNA hairpins immobilized on a gold surface retain their ability to bind complementary DNA sequences selectively.
authors.affiliation: Department of Chemistry, and The Center for Future Health, University of Rochester, Rochester, New York 14627, USA.
authors.forename: Hui
authors.initials: H
authors.lastname: Du
authors.forename: Matthew D
authors.initials: MD
authors.lastname: Disney
authors.forename: Benjamin L
authors.initials: BL
authors.lastname: Miller
authors.forename: Todd D
authors.initials: TD
authors.lastname: Krauss
mesh_terms: D001426:Bacterial Proteins / Q000235:genetics; D001483:Base Sequence; D015374:Biosensing Techniques / Q000379:methods*; D004269:DNA, Bacterial / Q000032:analysis / Q000737:chemistry* / Q000235:genetics; D005456:Fluorescent Dyes / Q000737:chemistry; D006046:Gold / Q000737:chemistry*; D008856:Microscopy, Fluorescence; D009690:Nucleic Acid Conformation; D009693:Nucleic Acid Hybridization; D009841:Oligonucleotides / Q000032:analysis*; D012235:Rhodamines / Q000737:chemistry; D013211:Staphylococcus aureus / Q000235:genetics; D013499:Surface Properties
chemical_list: D001426:Bacterial Proteins; D004269:DNA, Bacterial; C096686:FemA protein, Bacteria; D005456:Fluorescent Dyes; D009841:Oligonucleotides; D012235:Rhodamines; D006046:Gold