Excimer formation by hybridization using two pyrene-labeled oligonucleotide probes.

Pyrene excimer formation was achieved in an aqueous solution by nucleic acid hybridization. We used two different 16-mer oligonucleotide probes which had a combined continuous-sequence run complimentary to a target 32-mer. Prior to hybridization, the adjacent terminal ends (i.e., the 3'-terminal of one probe and the 5'-terminal of the other probe) were each labeled with one pyrene residue. The simultaneous hybridization of the probes to the target induced a 495-nm broad fluorescence band characteristic for pyrene excimer. Temperature and molecular configurations of the hybrid influenced the excimer formation.