The present invention relates to a method of detecting a target nucleic acid on the basis of rolling circle amplification (RCA), and more specifically, to a method of detecting a target nucleic acid, the method in which a target nucleic acid (a nucleic acid having a target nucleic acid sequence), when present, forms a circular template with a template for performing an amplification reaction, wherein during the amplification reaction, a restriction enzyme is added to further induce a new RCA reaction, thus increasing the reaction rate and sensitivity, and to an RCA composition for implementing the method. The method of detecting a target nucleic acid according to the present invention, by detecting a barcode sequence predefined according to the type of the target nucleic acid, enables multiple detections of the presence of the target nucleic acid without sequencing, is inexpensive for not using costly enzymes, such as CRISPR, can detect barcode sequences, and can utilize various existing nucleic acid detection systems, and thus, can be useful in the detection of gene mutations.

A structured substrate includes a substrate body having an active side. The substrate body includes reaction cavities that open along the active side and interstitial regions that separate the reaction cavities. The structured substrate includes an ensemble amplifier positioned within each of the reaction cavities. The ensemble amplifier includes a plurality of nanostructures configured to at least one of amplify electromagnetic energy that propagates into the corresponding reaction cavity or amplify electromagnetic energy that is generated within the corresponding reaction cavity.

A structured substrate includes a substrate body having an active side. The substrate body includes reaction cavities that open along the active side and interstitial regions that separate the reaction cavities. The structured substrate includes an ensemble amplifier positioned within each of the reaction cavities. The ensemble amplifier includes a plurality of nanostructures configured to at least one of amplify electromagnetic energy that propagates into the corresponding reaction cavity or amplify electromagnetic energy that is generated within the corresponding reaction cavity.

The invention generally relates to assemblies for displacing droplets from a vessel that facilitate the collection and transfer of the droplets while minimizing sample loss. In certain aspects, the assembly includes at least one droplet formation module, in which the module is configured to form droplets surrounded by an immiscible fluid. The assembly also includes at least one chamber including an outlet, in which the chamber is configured to receive droplets and an immiscible fluid, and in which the outlet is configured to receive substantially only droplets. The assembly further includes a channel, configured such that the droplet formation module and the chamber are in fluid communication with each other via the channel. In other aspects, the assembly includes a plurality of hollow members, in which the hollow members are channels and in which the members are configured to interact with a vessel.

A methodology for assays and diagnostics utilizes a nanoporous or corrugated metal-containing surface, fiber or particle which enhances or suppresses the optical detectability of a label. The resulting optical, electromagnetic, or imaging signal signals the presence of a pathogen or analyte of interest. Preferred embodiments pertain to label-free, in situ monitoring of individual DNA hybridization in microfluidics using molecular sentinel probes immobilized on nanoporous gold disks. By immobilizing molecular sentinel probes on nanoporous gold disks, single-molecule sensitivity is demonstrated via surface-enhanced Raman scattering which provides robust signals. The described methodology is generally applicable to most amplification independent assays and molecular diagnostics.

A methodology for assays and diagnostics utilizes a nanoporous or corrugated metal-containing surface, fiber or particle which enhances or suppresses the optical detectability of a label. The resulting optical, electromagnetic, or imaging signal signals the presence of a pathogen or analyte of interest. Preferred embodiments pertain to label-free, in situ monitoring of individual DNA hybridization in microfluidics using molecular sentinel probes immobilized on nanoporous gold disks. By immobilizing molecular sentinel probes on nanoporous gold disks, single-molecule sensitivity is demonstrated via surface-enhanced Raman scattering which provides robust signals. The described methodology is generally applicable to most amplification independent assays and molecular diagnostics.

Systems, methods, and devices related to detecting a presence of an analyte and/or determining a concentration of analytes are provided. An analyte may be provided on an LSPR-active surface. The LSPR-active surface may comprise sensitivity enhancing labels. The analyte may induce a local change near the LSPR-active surface. The LSPR-active surface may be imaged with an imaging device for images before, during, or after a reaction takes place. Local regions of interest within the images may be analyzed to detect the local changes.

Systems, methods, and devices related to detecting a presence of an analyte and/or determining a concentration of analytes are provided. An analyte may be provided on an LSPR-active surface. The LSPR-active surface may comprise sensitivity enhancing labels. The analyte may induce a local change near the LSPR-active surface. The LSPR-active surface may be imaged with an imaging device for images before, during, or after a reaction takes place. Local regions of interest within the images may be analyzed to detect the local changes.

A method of DNAzyme activity in a fluid by a sensor that is manufactured as follows. A method of manufacturing a fiber optic surface plasmon resonance sensor tip for sensing DNAzyme activity in a fluid, the method comprising, a) providing an fiber optic surface plasmon resonance sensor (FO-SPR) tip comprising at least one first single strand DNA with distinct sequence (immobilized on the sensing surface of said the fiber optic surface plasmon resonance sensor tip, b) providing gold nanoparticles (AuNPs) comprising a second single strand DNA with distinct sequence immobilized on said the gold nanoparticles, c) providing a third distinct DNA sequence ligation template for said first and second single strand for DNA hybridizing the third distinct DNA sequence ligation template in part with said the first single strand DNA and in part with the second single strand DNA to form one FO-SPR probe and AuNP-probe complex and d) providing a selected ligase to ligate together to a selected single strand DNA construct between AuNP and FO-SPR adapted to function as a selected DNAzyme FO-SPR-AuNP-probe. An aspect of present invention is a surface plasmon resonance (SPR) real-time monitoring system of NAzyme cleavage activity manufactured by ligation of a metallic nanoparticle (NP)-labelled DNA-sequences to a SPR sensing surface and yet more particular by ligation of AuNP-labelled DNA-sequences to a FO-SPR gold surface. Furthermore, incorporation of temporary inactivating the NAzyme with an inhibitor strand or a NAzyme blocking DNA sequence, containing an internal loop for target recognition independent of the catalytic activity from the NAzyme binding arms in the SPR sensor, e.g. FO-SPR sensor, allows real-time monitoring system of NAzyme cleavage activity in function of binding of selected targets (peptides, polypeptides, protein, small molecules, nucleotides, fat groups) to the internal loop of said the inhibitor strand.

A method of DNAzyme activity in a fluid by a sensor that is manufactured as follows. A method of manufacturing a fiber optic surface plasmon resonance sensor tip for sensing DNAzyme activity in a fluid, the method comprising, a) providing an fiber optic surface plasmon resonance sensor (FO-SPR) tip comprising at least one first single strand DNA with distinct sequence (immobilized on the sensing surface of said the fiber optic surface plasmon resonance sensor tip, b) providing gold nanoparticles (AuNPs) comprising a second single strand DNA with distinct sequence immobilized on said the gold nanoparticles, c) providing a third distinct DNA sequence ligation template for said first and second single strand for DNA hybridizing the third distinct DNA sequence ligation template in part with said the first single strand DNA and in part with the second single strand DNA to form one FO-SPR probe and AuNP-probe complex and d) providing a selected ligase to ligate together to a selected single strand DNA construct between AuNP and FO-SPR adapted to function as a selected DNAzyme FO-SPR-AuNP-probe. An aspect of present invention is a surface plasmon resonance (SPR) real-time monitoring system of NAzyme cleavage activity manufactured by ligation of a metallic nanoparticle (NP)-labelled DNA-sequences to a SPR sensing surface and yet more particular by ligation of AuNP-labelled DNA-sequences to a FO-SPR gold surface. Furthermore, incorporation of temporary inactivating the NAzyme with an inhibitor strand or a NAzyme blocking DNA sequence, containing an internal loop for target recognition independent of the catalytic activity from the NAzyme binding arms in the SPR sensor, e.g. FO-SPR sensor, allows real-time monitoring system of NAzyme cleavage activity in function of binding of selected targets (peptides, polypeptides, protein, small molecules, nucleotides, fat groups) to the internal loop of said the inhibitor strand.