65 results about "Nucleic Acid Probes" patented technology

The invention provides a nucleic acid probe, a primer group, a kit, a detection method and application, and relates to the technical field of biology. The nucleotide sequence of the nucleic acid probe is as shown in SEQ ID NO. 1; wherein the 3'end of the nucleic acid probe is modified with MGB, and locked nucleic acid is modified at a base position corresponding to the difference between the swine fever wild strain and the swine fever vaccine strain in the nucleotide sequence. According to the nucleic acid probe, a specific sequence is utilized to precisely target a swine fever wild strain, and locked nucleic acid modification is introduced at a differential site, so that the recognition capability on single-base mismatch is remarkably enhanced, non-specific binding to a vaccine strain is thoroughly blocked, and false positive interference is eliminated; and 3 '-terminal MGB modification is matched to improve the binding stability and sensitivity, so that the efficient and accurate identification of the swine fever wild strain under the immune background is ensured.

The present invention generally relates to systems and methods for imaging or determining nucleic acids, for instance, within cells. In some embodiments, the transcriptome of a cell may be determined. Certain embodiments are directed to determining nucleic acids, such as mRNA, within cells at relatively high resolutions. In some embodiments, a plurality of nucleic acid probes may be applied to a sample, and their binding within the sample determined, e.g., using fluorescence, to determine locations of the nucleic acid probes within the sample. In some embodiments, codewords may be based on the binding of the plurality of nucleic acid probes, and in some cases, the codewords may define an error-correcting code to reduce or prevent misidentification of the nucleic acids. In certain cases, a relatively large number of different targets may be identified using a relatively small number of labels, e.g., by using various combinatorial approaches.

The invention relates to the technical field of molecular diagnosis and graphic processing, in particular to an electronic microarray chip dot matrix negative and positive judgment method based on an ISFET sensor. A chip hole site corresponds to an ISFET sensor, and after a hole bottom specific nucleic acid probe and a target sequence are hybridized and extended, the voltage of the sensor is changed. The method specifically comprises the following steps: data preprocessing: filtering median values of multi-frame electric signals of a hole site and taking a mean value; the dot matrix identification comprises the steps of threshold demarcation, Canny edge detection, circular Hough transform, optimal circle screening by Kdtree, array numbering and abnormal deletion processing to position a dot matrix; and calculating a result, extracting a signal difference value of the D1 stage and the D4 stage, evaluating numerical values of the positive quality control array and the to-be-detected sample array through a numerical value of the negative quality control array, and judging a final calculation result. According to the method, response changes are rapidly analyzed through image recognition, false detection and missing detection caused by numerical value differences in different arrays are reduced through multiple times of detection, and the detection accuracy is improved by selecting the most possible area through tickets.

The invention discloses a preparation method of a space chip, the space chip and application of the space chip, the preparation method comprises the following steps: hybridizing: connecting a single-stranded nucleic acid molecule to the surface of a solid-phase substrate, the single-stranded nucleic acid molecule comprises a first fixed sequence, a space bar code sequence, a sequencing primer binding sequence and a second fixed sequence, the surface of the solid-phase substrate of the chip substrate is connected with a first probe, and the first probe comprises a first fixed sequence complementary sequence and a second fixed sequence complementary sequence; carrying out ring closing to enable the single-stranded nucleic acid molecules to form annular nucleic acid molecules; carrying out rolling circle amplification; sequencing to obtain sequence information of the space bar code sequence; synthesizing single-stranded nucleic acid molecules by taking the rolling circle amplification product as a template to obtain a single-stranded nucleic acid molecule library; fixing and clustering: fixing the single-stranded nucleic acid molecule library on the surface of a solid-phase substrate to form a single-stranded nucleic acid molecule cluster. According to the invention, the chip with the nucleic acid probe carrying spatial position coordinate information can be prepared.

The invention discloses a synthesis method of 2 '-O-methyladenosine, and belongs to the technical field of nucleoside synthesis and medicinal chemistry. According to the method, xylose which is rich in source is taken as an initial raw material, eight-step reaction including acetalation protection, acetylation, glycosylation, deacetylation, methylation, deacetalation protection, Mitsunobu reaction and secondary deacetylation is performed, reaction conditions of each step are accurately controlled, and finally, a target product is synthesized. The method has the advantages of high methylation reaction regioselectivity, mild reaction conditions, cheap and easily available raw materials and controllable cost, and overcomes the problems of poor methylation reaction regioselectivity, harsh reaction conditions and high cost in the existing synthesis method. The obtained product has important application value in the fields of research and development of antiviral drugs, design of nucleic acid probes and the like.

The invention discloses an exosome detection method based on double-hairpin nucleic acid probe assembly, and belongs to the technical field of exosome detection. The exosome detection method comprises the following steps: step 1, constructing a multi-element hairpin probe H1; step 2, constructing a multi-element hairpin probe H2; 3, preparing a probe; 4, multi-element signal probes are assembled, in the step 4, three groups of H1 probes and H2 probes are arranged in total, the proportion of the first group of H1 probes and 400 nM H2 probes is 80 nM, the proportion of the second group of H1 probes and 300 nM H2 probes is 80 nM, and the proportion of the third group of H1 probes and 350 nM H2 probes is 80 nM; according to the exosome detection method based on double-hairpin nucleic acid probe assembly, parallel detection of different exosome surface markers can be achieved by constructing multiple hairpin probes H1 and H2, and meanwhile the requirements for high specificity and stability are met.

The present disclosure relates in some aspects to methods and systems for analyzing a biological sample comprising contacting the biological sample with a nucleic acid probe non-covalently associated with a monomethine cyanine dye or salt thereof. In some aspects, a signal associated with the monomethine cyanine dye or salt thereof is detected to determine the location of a target analyte in the biological sample.

The application belongs to the technical field of molecular detection, and discloses a medicinal material identification system and method; the method comprises the following steps: emitting a topological protection acoustic wave to concentrate DNA of medicinal materials, marking the DNA with a CdTe quantum dot-nucleic acid probe, scraping the sample to extract DNA and performing PCR amplification, designing a logic gate staple chain to prepare a light-controlled origami probe, and injecting a PZT chip nano-pore array to be light-activated, and then, through AFM analysis of free energy, the medicinal materials are identified; the application constructs a complete technical chain from molecular recognition to reliable storage, and comprehensively solves multiple technical bottlenecks of traditional methods in medicinal material identification.

The application discloses a circRNA detection method based on Argonaute protein and rolling circle amplification. The method comprises the following steps: mixing a sample containing target circRNA to be detected with a specific reverse transcription primer and reverse transcriptase to obtain long-chain cDNA; mixing the obtained long-chain cDNA with pfAgo, gDNA and a DNA nucleic acid probe to carry out a reaction, and calculating the content of the target circRNA according to the fluorescence signal of the reaction mixture; the nucleotide sequence of the gDNA is specifically complementary to the cDNA sequence obtained by reverse transcription of the circRNA; the sequence of the DNA nucleic acid probe is specifically complementary to the sequence of the cDNA after one cutting of the cDNA by the pfAgo; and the DNA nucleic acid probe is a single-stranded DNA probe with a fluorescent label. The application can realize high-sensitivity, high-specificity and multiple target simultaneous analysis and detection of potential diagnostic biomarkers of liver cancer such as hsa_circ_0001445 and hsa_circ_0001141.

The application discloses a kind of photoactivation manganese ion bridging type deoxyribozyme probe preparation and its application in Cistanche inhibiting acetylcholinesterase activity.The probe is pSD@MnO2 Composite structure, which is composed of manganese dioxide nanosheet and functional nucleic acid assembly adsorbed on its surface, the assembly includes S chain labeled with fluorescence / quenching group and containing deoxyribozyme cleavage site, and pD chain partially hybridized with S chain and containing photocleavage site.Its preparation includes nucleic acid probe assembly, MnO2 Nanosheet complexing and purification steps.When applied, AChE catalytic product decomposes MnO2, releases Mn 2+ And nucleic acid chain; after centrifugation, pD chain is cut by ultraviolet light activation trigger, and released DNAzyme is cut under the assistance of Mn 2+ It produces amplified fluorescence signal; by comparing signal change before and after adding inhibitor, inhibition activity can be quantitatively evaluated.The application combines photocontrol activation with enzyme cascade amplification, realizes high sensitivity and operation synchronism of detection process, and is especially suitable for high-throughput rapid screening of AChE inhibitor in Cistanche and other natural products.

This invention discloses a field-effect transistor biosensor based on a framework nucleic acid-gold nanoparticle composite structure and its fabrication method, comprising the following steps: 1) providing a carbon nanotube field-effect transistor substrate; 2) depositing a hafnium oxide dielectric layer on the surface of the carbon nanotube channel; 3) depositing gold nanoparticles on the surface of the hafnium oxide dielectric layer; 4) preparing a tetrahedral framework nucleic acid probe; 5) adding the probe solution to the surface of the gold nanoparticles for incubation and fixation; 6) sealing unreacted sites on the surface of the gold nanoparticles and washing with buffer solution. This invention achieves precise interface modification through atomic layer deposition, electron beam evaporation, and gold-sulfur bond anchoring. It utilizes the rigid structure of the tetrahedral framework nucleic acid to achieve precise, directional, and spaced probe distribution, effectively overcoming Debye shielding limitations and reducing non-specific adsorption. The sensor exhibits ultra-high sensitivity, excellent stability and reusability, strong specificity, and good versatility, and can be used for highly sensitive and specific detection of various targets such as nucleic acids and proteins.

The invention discloses a micro-nano robot based on a DNA tetrahedron nucleic acid probe and magnetic driving and a preparation method and application of the micro-nano robot. A DNA tetrahedron probe (DTP) constructed by a DNA tetrahedron framework (DTH), a double-hairpin structure (H1 and H2) and a double-strand recognition module (dsDNA) is adopted, signal amplification detection can be performed on two breast cancer subtype related miRNAs, namely miR-21 and miR-31, and the probe is combined with magnetic nanoparticles, so that active mixing and enrichment of the probe and a target are realized under the action of an external rotating magnetic field, and the detection sensitivity is high. And through dual-channel fluorescence logic output, the kit has the advantages of high sensitivity, high specificity, short reaction time, visual typing, good biocompatibility and the like.

The invention relates to a biomarker combination comprising an NF-kappa B activation marker and a nucleic acid probe or primer for determining the mRNA expression levels of one or more genes of BCL2A1, CCL3, G0S2, IL1beta and TNF alpha, the expression levels of at least three of said genes being significantly increased relative to a reference control; the invention also relates to a detection kit, which comprises a reagent for detecting the NF-kappa B activation marker and a nucleic acid probe or primer for determining the gene combination expression level of the BCL2A1, CCL3, G0S2, IL1beta and TNF alpha mRNA. In addition, the invention relates to a method for preparing the detection kit by using a computer program. According to the invention, the activation state of an NF-kappa B signal channel is combined with the expression characteristics of specific inflammation-related genes for the first time, and a stable and consistent ASD molecular diagnosis system is constructed.

The invention belongs to the technical field of biology, and discloses a DNA tetrahedral probe for live oocyte mitochondrial ATP imaging and application of the DNA tetrahedral probe. The invention provides a DNA tetrahedron delivery-based nucleic acid probe for fixed-point trigger cascade nucleic acid reaction, which can realize high-sensitivity and rapid detection of mitochondrial ATP of living oocytes. The nucleic acid probe is stable in structure and high in specificity, can accurately distinguish similar 12s rRNA and ATP analogues (such as CTP, GTP and UTP), remarkably reduces false positive signals, and ensures the reliability of detection results. The nucleic acid probe realizes ATP in-situ imaging at a mitochondrial level, is helpful for deep evaluation of an oocyte energy state, provides key indexes for quality reduction of oocytes of elderly women and evaluation of embryonic development potential, and has positive significance in improvement of assisted reproductive outcome.

The present invention discloses a nucleic acid probe combination for detecting rifampicin resistance gene mutation of Mycobacterium tuberculosis, comprising: a plurality of probes for a nucleic acid amplification reaction, each of the plurality of probes being completely complementary to a corresponding one of a plurality of mutant sequences in a drug resistance determining region of an rpoB gene, and at least one of the plurality of probes has a locked nucleic acid (LNA) modification.

The application discloses a digoxin nanobody and a preparation method and application thereof. The amino acid and nucleotide sequences of the digoxin nanobody are shown in SEQ ID NO. 8-9. The antibody has good affinity to a target antigen, and the dissociation constant Kd value is about 73.1 nM, and can be used for digoxin content determination, nucleic acid probe detection and in-vivo digoxin neutralization and detoxification. The antibody has the advantages of small volume, high stability, low cost, low immunogenicity and the like, and has a good application prospect.

The invention discloses a kit for detecting influenza A H1N1 based on catalytic hairpin self-assembly lateral flow immunochromatography and application of the kit, and belongs to the field of influenza A virus nucleic acid detection. The influenza A H1N1 detection probe comprises a probe H1 with a nucleotide sequence as shown in SEQ ID NO.1; the nucleotide sequence of the probe H2 is as shown in SEQ ID NO. 2. According to the method, nucleic acid amplification reaction is carried out under a constant-temperature condition by virtue of the signal amplification capability of CHA, a catalytic hairpin probe freeze-drying technology is combined, and a reaction result is checked by virtue of a lateral flow immunochromatography technology, so that the influenza A virus nucleic acid can be quickly detected with high sensitivity and specificity without thermal cycle; and a solid foundation is hopeful to be laid for diagnosis and curative effect evaluation of influenza A virus in the future.

The invention discloses a method for promoting coupling of DNA oligonucleotides and macromolecules by using ice-phase confinement and application of the method, and belongs to the technical field of biological material preparation. The method comprises the following steps: freezing single-stranded DNA containing a terminal reaction group and a buffer solution of macromolecules to be coupled under the condition of-20 DEG C, and enriching solutes in a micro water sac area between ice crystals, so that local concentration and reaction site accessibility are remarkably improved, and various coupling chemistry (SPAAC, CuAAC, biotin-streptavidin and the like) can be quickly and freely completed by a template at low temperature. The method is high in universality, mild in condition and low in reagent consumption, high-efficiency construction of long-chain DNA, 3 '-3' / 5 '-5' inverted connection and internal site modification can be achieved, the coupling efficiency of antibody-DNA and BSA-DNA can be remarkably improved under the condition that protein conformation and functions are maintained, a valence-controllable nucleic acid-protein composite structure is achieved, and the method is suitable for industrial production. The method is suitable for the fields of nucleic acid probe development, protein engineering, nano material construction, drug delivery and the like.

The present invention generally relates to systems and methods for imaging or determining nucleic acids, for instance, within cells. In some embodiments, the transcriptome of a cell may be determined. Certain embodiments are directed to determining nucleic acids, such as mRNA, within cells at relatively high resolutions. In some embodiments, a plurality of nucleic acid probes may be applied to a sample, and their binding within the sample determined, e.g., using fluorescence, to determine locations of the nucleic acid probes within the sample. In some embodiments, codewords may be based on the binding of the plurality of nucleic acid probes, and in some cases, the codewords may define an error-correcting code to reduce or prevent misidentification of the nucleic acids. In certain cases, a relatively large number of different targets may be identified using a relatively small number of labels, e.g., by using various combinatorial approaches.

A method for predicting responsiveness to a HER2-directed therapy by assessing HER2 heterogeneity in a tumor includes contacting a sample of the tumor with a biomarker-specific reagent that specifically binds to HER2 protein and detecting HER2 protein in the sample, contacting the sample of the tumor with a first nucleic acid probe that specifically binds HER2 genomic DNA and detecting HER2 gene amplification status in the sample, contacting the sample of the tumor with a second nucleic acid probe that specifically binds HER2 RNA and detecting HER2 RNA status in the sample scoring the HER2 protein (IHC), HER2 gene (DISH), and HER2 RNA (RNA-ISH), predicting that the tumor is responsive to the HER2-directed therapy if the tumor reveals a first foci having a first score and a second score, in which the first score and the second score are not the same.

The application discloses a nucleic acid aptamer capable of specifically recognizing a cyanogen bromide-activated substrate material and application thereof. The nucleic acid aptamer can specifically bind to the cyanogen bromide-activated substrate material and comprises a nucleotide sequence selected from any one of SEQ ID NO: 1-4 in the sequence listing or a nucleotide sequence derived from the nucleotide sequence through substitution, deletion, insertion of one or more nucleotides and / or chemical modification. The application develops a novel nucleic acid probe immobilization method by utilizing the interaction between the nucleic acid aptamer and the cyanogen bromide-activated substrate material and applies the method in the fields of biosensing, affinity enrichment and separation and reagent kit development. In addition, by constructing a fusion allosteric nucleic acid aptamer, the interaction between the two can be used as a signal output strategy to realize detection of target objects such as nucleic acids, proteins, small molecules, cells and exosomes.

The invention relates to the field of mycobacterium abscessus gene detection, and particularly discloses a nucleic acid probe group for MLST typing identification of a mycobacterium abscessus complex group and application of the nucleic acid probe group. The nucleic acid probe group comprises a target probe and a high GC balance probe; the target probe comprises a nucleotide sequence which contains substitution, deletion or insertion of 0-20 nucleotides or any combination of the substitution, deletion or insertion of the 0-20 nucleotides relative to the nucleotide sequence as shown in SEQ ID NO.1-188; the high GC balance probe comprises a nucleotide sequence as shown in SEQ ID NO.189, wherein the nucleotide sequence contains substitution, deletion or insertion of 0-20 nucleotides or any combination of the substitution, deletion or insertion of the 0-20 nucleotides. According to the invention, efficient enrichment and synchronous detection of MLST typing related targets are realized for the first time.

The invention relates to an azobenzene quenching unit and a preparation method thereof, a solid-phase synthesis carrier and a preparation method thereof, and a nucleic acid probe. The azobenzene quenching unit has a structural general formula as follows: in the formula, R1, R2, R3, R4, R5, R6, R7, R8, R9, R10, R11, R12 and R13 are independently hydrogen, methyl, ethyl, propyl, isopropyl, phenyl, biphenyl, 2-furyl, 2-thienyl, methoxyl, ethyoxyl, isopropoxy, nitro, nitroso or cyano, n is equal to 0-6, and m is equal to 2-12. The azobenzene quenching unit contains a polyfluorocarboxylic acid connecting structure, the azobenzene quenching unit and amino on the surface of a solid-phase synthesis carrier form an amido bond through carboxylic acid of the polyfluorocarboxylic acid connecting structure, and the azobenzene quenching unit is connected to the solid-phase synthesis carrier and used for synthesizing nucleic acid. The synthesis yield of the 3 '-azobenzene quenching agent labeled nucleic acid can be effectively improved.

This disclosure generally relates to graphene-based diagnostic sensor devices. More particularly, the disclosure relates to graphene-based diagnostic sensor devices for the multiplex detection of target nucleic acids in fluid samples, including biological fluid samples. In certain aspects, the graphene-based multiplex diagnostic devices disclosed herein comprise a graphene-based FET sensor array chip, wherein each sensor in the array comprises an independent sensing regions, each sensing region having a nucleic acid probe attached to a graphene monolayer, for hybridizing and detecting a target nucleic acid.

This invention belongs to the field of biomedical technology, specifically relating to a method for eluting nucleic acid probes from biological samples, comprising the following steps: (1) obtaining a biological sample containing nucleic acid probes, and (2) immersing the biological sample in an elution solution containing quaternary phosphonium salt to elute the nucleic acid probes. This invention can achieve rapid and complete dissociation and elution of nucleic acid probes, thereby obtaining excellent multi-round staining cycle efficiency.

This invention discloses a hexavanadate-bridged double-ended click nucleic acid probe construct, its preparation method, and its application, relating to the field of bioanalytical technology. The hexavanadate-bridged double-ended click nucleic acid probe construct comprises a hexavanadate derivative V6-(N3)2 bridging scaffold with azido groups at both ends, and two identical oligonucleotides MB1 or MB2; MB1 is terminally alkyne and labeled with a FAM fluorescent group, and MB2 is terminally alkyne and labeled with a Cy5 fluorescent group; V6-(N3)2 and MB1 or MB2 undergo a Cu(I)-catalyzed azido-alkynyl cycloaddition reaction to form a 1,2,3-triazole linker bond, connecting to form an MB1-triazole-V6-triazole-MB1 or MB2-triazole-V6-triazole-MB2 structure. This invention also discloses a method for preparing this construct, wherein the finished product is obtained through a click reaction in an aqueous buffer system, copper removal and desalting, and separation and purification. And its application in nucleic acid sequence-specific detection, with its fluorescence quantitative readout mechanism, improves the robustness of sequence identification, mismatch detection and quantitative detection, and is suitable for pathogen identification, gene mutation screening, molecular diagnostics and drug companion diagnostics.

This disclosure relates to catalytic nucleic acids, catalytic nucleic acid probes, biosensors, lateral flow devices, and kits for detecting the presence or absence of eosinophil peroxidase. Also provided are methods for detecting the presence or absence of eosinophil peroxidase in a test sample, using the catalytic nucleic acids, catalytic nucleic acid probes, biosensors, lateral flow devices, and kits.

The present invention provides novel probes for use in LAMP detection methods. The probe comprises a single fluorophore label bound to an internal cytosine residue of the probe. The probes are particularly useful in the detection of Chlamydia and gonorrhea infections in patients.

The invention provides a visual microarray specific nucleic acid probe combination, system and method for detecting antibiotic resistance genes, and belongs to the technical field of environmental microbiological detection. According to a positive-sense strand and an antisense strand of double-stranded DNA of a target antibiotic resistance gene, a carboxylation fixed probe and a sulfhydrylation signal probe are respectively designed, and initial signal multiplication is realized through double-strand double recognition; and carrying out secondary amplification in combination with nanogold-catalyzed silver staining deposition to form a visual detection signal. The sensitivity of the method reaches 10 <-8 > mol, antibiotic resistance genes such as qepA, macB and the like in soil can be detected at high throughput, and the method has the advantages of high specificity, simplicity and convenience in operation and controllable cost, and provides technical support for environmental risk assessment.