Patent ID: 7582432

Claim:
A method for detecting a nucleic acid target sequence, said method comprising: (a) contacting said target sequence with a detector nucleic acid; comprising a single-stranded target binding sequence, said detector nucleic acid having linked thereto, i) a fluorophore; and ii) a quencher of excited state energy having a structure comprising at least three residues selected from aryl, substituted aryl, heteroaryl, substituted heteroaryl and combinations thereof, wherein at least two of said residues are covalently linked via an exocyclic diazo bond, wherein said detector nucleic acid is in a conformation allowing donor-acceptor energy transfer between said fluorophore and said quencher when said fluorophore is excited; (b) hybridizing said target binding sequence to said target sequence, thereby altering said conformation of said detector nucleic acid, causing a change in a fluorescence parameter; and (c) detecting said change in said fluorescence parameter, thereby detecting said nucleic acid target sequence.