Patent ID: 8859266

Claim:
A system for detecting a target analyte, the system comprising: (a) a first oligonucleotide probe comprising: (i) at the 5′-terminus thereof, a reporter oligonucleotide-binding arm having a nucleotide sequence complementary to the nucleotide sequence of a first region of a reporter oligonucleotide; and (ii) at the 3′-terminus thereof, an analyte-binding arm having a nucleotide sequence characterized as selectively binding to a first region of a target analyte; (b) a second oligonucleotide probe comprising: (i) at the 3′-terminus thereof, a reporter oligonucleotide-binding arm having a nucleotide sequence complementary to the nucleotide sequence of a second region of a reporter oligonucleotide; and (ii) at the 5′-terminus thereof, an analyte-binding arm having a nucleotide sequence characterized as selectively binding to a second region of a target analyte; (c) a reporter oligonucleotide comprising: (i) a first region having a nucleotide sequence complementary to the reporter oligonucleotide-binding arm of the first oligonucleotide probe; (ii) a second region having a nucleotide sequence complementary to the reporter oligonucleotide-binding arm of the second oligonucleotide probe; (iii) a fluorophore and a quencher disposed on the reporter oligonucleotide whereby said fluorophore and quencher interact in the absence of a target analyte to quench fluorescence generated by the fluorophore; and (iv) a cleavable site disposed between the fluorescent label and the quencher, wherein the cleavable site is characterized as cleavable by a protein enzyme; and wherein the target analyte, the first and second oligonucleotide probes, and the reporter oligonucleotide form a quadripartite complex, thereby providing a configuration of the cleavable site of the reporter oligonucleotide allowing said site to be cleaved by the protein enzyme.