Methods compositions and articles of manufacture for assaying a sample for a target polynucleotide are provided. A sample suspected of containing the target polynucleotide is contacted with a polycationic multichromophore and a sensor polynucleotide complementary to the target polynucleotide. The sensor polynucleotide comprises a signaling chromophore to receive energy from the excited multichromophore and increase emission in the presence of the target polynucleotide. The methods can be used in multiplex form. Kits comprising reagents for performing such methods are also provided.

Light harvesting luminescent multichromophores that are configured upon excitation to transfer energy to, and amplify the emission from, an acceptor signaling chromophore in energy-receiving proximity therewith are provided. Also provided are compositions for labelling a target. The labelling composition may include a donor light harvesting multichromophore and an acceptor signaling chromophore in energy-receiving proximity to the donor light harvesting multichromophore. Also provided is an aqueous composition for labelling a target, including: a donor light harvesting multichromophore; an acceptor signaling chromophore in energy-receiving proximity therewith; and a sensor biomolecule. Methods for using the subject compositions are also provided.

Light harvesting luminescent multichromophores that are configured upon excitation to transfer energy to, and amplify the emission from, an acceptor signaling chromophore in energy-receiving proximity therewith are provided. Also provided are compositions for labelling a target. The labelling composition may include a donor light harvesting multichromophore and an acceptor signaling chromophore in energy-receiving proximity to the donor light harvesting multichromophore. Also provided is an aqueous composition for labelling a target, including: a donor light harvesting multichromophore; an acceptor signaling chromophore in energy-receiving proximity therewith; and a sensor biomolecule. Methods for using the subject compositions are also provided.

A target (50) having a specific nucleic acid sequence included in a sample is measured using a detection probe (10) that has a detection part having a nucleic acid sequence complementary to the nucleic acid sequence of the target (50), a label molecule A (20) having a nucleic acid sequence that is complementary to the nucleic acid sequence of the target (50) and different from the nucleic acid sequence of the detection part, and a label molecule B (30) having a nucleic acid sequence complementary to the nucleic acid sequence of the label molecule A (20), in which a fluorescent molecule is attached to either one of the label molecule A (20) and the label molecule B (30), and the label molecule A (20) and the label molecule B (30) bind to each other at at least two or more sites to form a branched structural body of the label molecule A (20) and the label molecule B (30).

A target (50) having a specific nucleic acid sequence included in a sample is measured using a detection probe (10) that has a detection part having a nucleic acid sequence complementary to the nucleic acid sequence of the target (50), a label molecule A (20) having a nucleic acid sequence that is complementary to the nucleic acid sequence of the target (50) and different from the nucleic acid sequence of the detection part, and a label molecule B (30) having a nucleic acid sequence complementary to the nucleic acid sequence of the label molecule A (20), in which a fluorescent molecule is attached to either one of the label molecule A (20) and the label molecule B (30), and the label molecule A (20) and the label molecule B (30) bind to each other at at least two or more sites to form a branched structural body of the label molecule A (20) and the label molecule B (30).

The disclosure relates to novel compositions comprising an electrochemiluminescence (ECL) co-reactant. In embodiments, the composition further comprises an ionic component, a surfactant, or combination thereof. In embodiments, the ECL co-reactant is triethanolamine (TEA), tert-butyldiethanolamine (tBDEA), methyldibutylethanolamine (MDEA), 3-[Bis-(2-hydroxy-ethyl)-amino]-propane-1-sulfonic acid (DEA-PS), or a combination thereof. Methods of using the compositions and kits comprising the compositions are also provided herein, including methods using ECL-labeled oligonucleotide probes having quenching moieties.

The disclosure relates to novel compositions comprising an electrochemiluminescence (ECL) co-reactant. In embodiments, the composition further comprises an ionic component, a surfactant, or combination thereof. In embodiments, the ECL co-reactant is triethanolamine (TEA), tert-butyldiethanolamine (tBDEA), methyldibutylethanolamine (MDEA), 3-[Bis-(2-hydroxy-ethyl)-amino]-propane-1-sulfonic acid (DEA-PS), or a combination thereof. Methods of using the compositions and kits comprising the compositions are also provided herein, including methods using ECL-labeled oligonucleotide probes having quenching moieties.

A nucleic acid probe for detecting a target nucleic acid. At least one terminal of the probe-binding region in the target nucleic acid is a guanine base, and one or more cytosine bases are present within 1 to 7 bases from the guanine base. The nucleic acid probe comprises an oligonucleotide having a cytosine base facing the guanine base on a terminal and a fluorescent dye conjugated to the cytosine base. The fluorescent dye is quenched by the interaction with a guanine base. The oligonucleotide is completely complementary to the nucleic acid in the probe-binding region except the one or more cytosine bases present within 1 to 7 bases from the terminal guanine base. The base in the oligonucleotide facing the cytosine base closest to the terminal guanine base among the one or more cytosine bases is a base having no fluorescence-quenching effect.

A nucleic acid probe for detecting a target nucleic acid. At least one terminal of the probe-binding region in the target nucleic acid is a guanine base, and one or more cytosine bases are present within 1 to 7 bases from the guanine base. The nucleic acid probe comprises an oligonucleotide having a cytosine base facing the guanine base on a terminal and a fluorescent dye conjugated to the cytosine base. The fluorescent dye is quenched by the interaction with a guanine base. The oligonucleotide is completely complementary to the nucleic acid in the probe-binding region except the one or more cytosine bases present within 1 to 7 bases from the terminal guanine base. The base in the oligonucleotide facing the cytosine base closest to the terminal guanine base among the one or more cytosine bases is a base having no fluorescence-quenching effect.

The present invention relates to catalytic, nucleic acid nanostmctures that enable versatile detection of RNAs, their use, and devices comprising same. The nanostructure comprises a DNA polymerase enzyme, a DNA aptamer and an inverter oligonucleotide, wherein the DNA aptamer comprising (i) a conserved sequence region for binding to the DNA polymerase enzyme, wherein the binding inactivates the polymerase activity, (ii) a variable sequence region for binding to the inverter oligonucleotide, and (iii) a duplex stabilizer region that lies between the conserved sequence region and the variable sequence region. The present invention also relates to the use of the nanostructure in a method of detection of nucleic acid for diagnosing a disease in a subject.