부산대학교 도서관

A new class of molecular beacons were developed in which pyrone fluorophores were connected both at 3' and 5' ends of a single-stranded oligonucleotide. The two pyrone-based fluorophores were synthesized from the same starting material, so that the preparation of the beacons was simplified. The detection strategy of the beacons for target DNAs is based on "excimer-monomer emission switching" of the pyrone fluorophores: excimer emission of the pyrone moieties changed to monomer one when the beacons hybridized with the targets. This type of two-state mode of fluorescence allows unambiguous detection of the target DNAs because strict 1:1 correlation between the nonhybridized and the hybridized beacons can be monitored by the presence of isoemissive points of the fluorescence changes. The beacons can detect target 19-mer DNAs and can discriminate the targets from their single-nucleotide mismatches at 1 nM concentration. Advantages of the excimermonomer switching molecular beacons were discussed in comparison with conventional ones. [ABSTRACT FROM AUTHOR]