Catalytic nucleic acid and gold nanoparticles for detection of biomolecules
AssigneeThe Governing Council of the University of Toronto
InventorsWarren Che Wor CHAN, Kyrylo ZAGOROVSKY
Life of this patent
Estimating the term…
Abstract
The present invention relates to catalytic nucleic acid molecule signal amplification combined with surface plasmon properties of gold nanoparticles to achieve simple and sensitive colorimetric detection of biological targets. The assays of the present invention have about 50 pM sensitivity without the need for purification steps, can detect multiple targets in parallel, and is easily adaptable to new targets. The methods of the present invention are capable of rapid detection of genetic targets for gonorrhea, syphilis, malaria, and hepatitis B infections.
Claims21
A method of detecting the presence of a biological target in a sample, characterized in that the method comprises:
- (a) contacting the sample with:
- (i) an un-catalyzed nucleic acid substrate,
- (ii) a catalytic nucleic acid, the catalytic nucleic acid configured for catalyzing the substrate solely in the presence of the target, and
- (iii) gold nanoparticles (GNPs), the GNPs functionalized with a linking moiety for assembling with the un-catalyzed nucleic acid substrate;
- and
- (b) analyzing the sample to determine whether the GNPs are in a substantially dispersed form or in an assembled form with the un-catalyzed nucleic acid substrate, wherein the GNPs being in the substantially dispersed form is indicative that the target is present in the sample.
A method of simultaneously detecting the presence of a number of different biological targets of interest in a sample, characterized in that the method comprises:
- (a) mixing the sample suspected of having the number of different biological targets with target-specific sets of (i) target-specific un-catalyzed nucleic acid substrates and (ii) target-specific catalytic nucleic acids, the catalytic nucleic acids in each target-specific set configured for catalyzing the un-catalyzed substrate solely in the presence of its target;
- (b) contacting the mixture of step (a) with separate target-specific populations of GNPs, the GNPs in each target-specific population functionalized with a linking moiety for assembling with its corresponding target-specific un-catalyzed nucleic acid substrate;
- and
- (c) determining for each separate target-specific population of GNPs whether the target-specific GNPs are in an assembled form with the corresponding target specific un-catalyzed substrate or in a substantially dispersed form, wherein the target-specific GNPs being in the substantially dispersed form in one population is indicative that the target corresponding to this population of target-specific GNP is present in the sample.
A kit for detecting a biological target of interest in a sample, characterized in that the kit comprises:
- (a) an un-catalyzed nucleic acid substrate, (b) catalytic nucleic acid capable catalyzing the un-catalyzed substrate solely in the presence of the target, and (c) GNPs functionalized with a linking moiety to assemble with the un-catalyzed nucleic acid substrate.
Dependencies are inferred from the claim text.