We have developed a new molecular beacon for DNA hybridization studies at an interface. Molecular beacons are a new class of oligonucleotides that can report the presence of specific nucleic acids in homogenous solutions. They are capable of forming a hairpin loop with a fluorophore and a quencher attached to the two ends of a stem.
Molecular beacons emit an intense fluorescent signal only when hybridized to their target molecules.
This provides excellent selectivity for the detection of DNA molecules. It can be immobilized onto a silica surface through biotin-avidin binding. The surface immobilized molecular beacons have been used for DNA hybridization with subnanomolar analytical sensitivity. The new molecular beacon is optically stable since a rhodamine dye is used as the fluorophore. The newly designed molecular beacons are intended for the development of ultrasensitive DNA sensors, for DNA molecular interaction studies at an interface and for biomedical diagnostics.