172 results about "Biotinylation" patented technology

The invention relates to a second antibody for resisting mouse IgG and rabbit IgG as well as a preparation method and application of the second antibody. The second antibody of the anti-mouse IgG and the rabbit IgG sequentially comprises an anti-mouse IgG nano antibody, a biotin fixed-point binding peptide fragment and an anti-rabbit IgG nano antibody from an amino terminal to a carboxyl terminal. According to the design of the second antibody of the anti-mouse IgG and rabbit IgG with a brand-new structure and the preparation method, high-efficiency expression is realized, the second antibody of the anti-mouse IgG and rabbit IgG capable of realizing fixed-point biotinylation is obtained, the second antibody can be further subjected to various modification reformation based on a biotin-streptavidin bridge, the preparation method of the second antibody of the polymerase labeled anti-mouse IgG and rabbit IgG is further developed, and the application of the second antibody of the polymerase labeled anti-mouse IgG and rabbit IgG is expanded. According to the method, the polymerase-labeled mouse-rabbit universal secondary antibody with similar affinity to mouse IgG and rabbit IgG is obtained, the preparation period of the secondary antibody can be shortened, the preparation process of the secondary antibody is simplified, the stability between batches is improved, and meanwhile, the dependence on experimental animals is reduced.

The invention belongs to the technical field of biological detection, and provides a multiple cell factor detection kit in tumor immunity and a preparation method and application thereof, and the detection kit comprises a capture antibody, a detection antibody, a mixed protein standard substance, a diluent and a washing buffer solution. The capture antibody is prepared by coupling a biotinylated antibody with a fluorescent microsphere coated with biotin to obtain a capture antibody coupled with a fluorescent encoding microsphere, and the detection antibody is prepared by coupling derivatized phycoerythrin PE-SMCC with a specific thioether bond of a sulfhydrylated antibody to obtain a fluorescent labeled antibody; the mixed protein standard substance adopts a freeze-drying protection system containing BSA, trehalose and the like. The single hole of the kit can synchronously detect various cell factors, the sample dosage is only 25 microliters, the kit is suitable for immune monitoring of iron overload and other chronic inflammation models, compared with a traditional ELISA method, the efficiency is improved by 10 times, the cost is reduced, and the kit has the remarkable advantages of being high in throughput, wide in linear range and high in stability.

The present application provides a detection method and use for neutralizing antibodies for therapeutic monoclonal antibodies, which is a CLB NAb assay developed through target-based drug depletion and drug-based NAb extraction for CMAB009 with high drug and target tolerance. Acid is typically used in the pretreatment of a sample to dissociate the drug / NAb complex. In order to improve the treatment effect, a two-step method involving an amphiphilic method and a bead method is adopted. Initially, EGFR-coated magnetic beads (target beads) are used to eliminate the majority of free drugs in a sample. Subsequently, after acid dissociation of the sample, NAb is captured with beads. NAb is neutralized and eluted by acid, and a biotinylated drug is added into an EGFR-coated flat plate for detecting NAb. A comprehensive experiment strategy is implemented, meanwhile, drug interference is relieved, and target tolerance is enhanced. Through troubleshooting and optimization, NAb determination is verified to be used for clinical sample analysis, so that the NAb is successfully applied to III-stage clinical immunogenicity NAb detection of CMAB009. The result shows that the integrated detection optimization strategy can greatly improve the key performance characteristics of CLB NAb detection, so that the potential immunogenicity and the influence of the potential immunogenicity on better biological development can be evaluated more reliably.

The invention belongs to the technical field of biology, and particularly discloses a pH response type probiotic-liposome hybrid system, a preparation method and application thereof, and the pH response type probiotic-liposome hybrid system comprises engineered escherichia coli Nissle 1917, pinocembrin-loaded biotinylated liposome and an enteric polymer; wherein the engineered escherichia coli Nissle 1917 is in non-covalent binding with the biotinylated liposome loaded with the pinocembrin through surface display streptavidin, so that EcNPIN is formed, and the EcNPIN is coated with an enteric polymer, so that the pH response type probiotic-liposome hybrid system is formed. The pH response type probiotic-liposome hybrid system EcNPIN-L provided by the invention can resist the acidic environment of the stomach, completes pH response release and colonization in the intestinal tract, solves the problems of lack of intestinal tract localization of drugs and low probiotic treatment efficiency, improves the local intestinal tract concentration of pinocembrin, and promotes intestinal tract colonization of probiotics.

A method and kit are provided for detecting anti-drug antibodies (ADAs) against self-assembling trimeric biologics, such as XPro1595, a pegylated variant of soluble human Tumor Necrosis Factor, in biological samples, particularly human serum. The method employs an Affinity Capture Elution-Protein A / G (ACE-AG) assay that overcomes non-specific reagent interactions inherent in conventional bridging and standard ACE assays due to the biologic's dynamic monomer exchange. The assay utilizes a two-plate system: a streptavidin-coated plate with biotinylated trimeric biologic captures ADAs, which are eluted, neutralized, and transferred to a protein A / G-coated plate for specific immunoglobulin capture and detection with a sulfo-tagged trimeric biologic via electrochemiluminescence. The kit includes pre-coated plates, labeled biologics, elution and neutralization solutions, assay buffer, confirmatory reagent, and instructions. The assay offers a robust, specific, and sensitive solution for immunogenicity testing of trimeric biologics.

The invention discloses a ctEVs separation and analysis method with time resolution capability and application thereof. The ctEVs separation and analysis method comprises the following steps: S1, culturing cells by adopting glycometabolism markers; or injecting the animal by adopting a glycometabolism marker; step S2, manufacturing a fishbone-shaped micro-fluidic chip modified by streptavidin; s3, separating and analyzing the new tumor source extracellular vesicles by the micro-fluidic chip, and co-incubating the extracellular vesicles and the aptamer probe co-modified by Biotin and DBCO to realize biotinylation of the new tumor source extracellular vesicles; the aptamer probe is a heterologous multivalent aptamer probe; step S4, capturing biotin-labeled target extracellular vesicles by adopting a chip; and S5, acquiring a chip image by using a fluorescence microscope, and analyzing the concentration of the target extracellular vesicles in the sample according to a fluorescence signal. The method can be used for screening tumor circadian rhythm markers and the like.

The invention discloses a brain-derived Tau protein single-molecule fluorescence immunoassay detection kit and a use method, the kit provided by the invention is composed of a BD-Tau magnetic bead reagent coated with a capture antibody, a BD-Tau calibrator, a BD-Tau quality control product, a biotinylated BD-Tau Detector reagent for detecting the antibody, a BD-Tau SBG reagent, an RGP reagent and a BD-Tau sample diluent, the magnetic bead concentration of the BD-Tau magnetic bead reagent is 0.04 mg / mL-0. 08mg / mL of carboxyl magnetic beads, the carboxyl magnetic beads are coated with Tau J5.H3 coated antibodies, the detection antibody in the BD-Tau Detector reagent of the biotinylated detection antibody is Tau12, the concentration of the detection antibody is 0.3 mu g / mL-0. 8mu g / mL, and the concentration of SBG in the BD-Tau SBG reagent is 40 pM-60 pM; the kit disclosed by the invention can be used by adopting any one of a one-step method, a two-step method or a three-step method to detect the content of the BD-Tau protein in a plasma sample, the detection limit is 0.050 pg / mL, and the detection range is 0.050 pg / mL-150 pg / mL; according to the invention, the specificity, accuracy and reliability of determination of the Alzheimer's disease are improved, and the problems of early diagnosis and early screening of the Alzheimer's disease are solved.

The invention belongs to the technical field of biological detection, and provides a multiple cell factor detection kit in macrophage polarization and a preparation method and application thereof, and the detection kit comprises a capture antibody, a detection antibody, a mixed protein standard substance, a diluent and a washing buffer solution. The capture system is used for preparing a capture antibody coupled with a fluorescence coding microsphere by coupling a biotinylated antibody with a fluorescence microsphere coated with biotin, and the detection system is used for preparing a fluorescence labeled antibody by coupling derivatized phycoerythrin PE-SMCC with a specific thioether bond of a sulfhydrylated antibody. The mixed protein standard substance adopts a freeze-drying protection system containing BSA, trehalose and the like. The single hole of the kit can synchronously detect multiple cell factors, the sample dosage is only 25 microliters, the kit is suitable for in-vitro tests of mouse mononuclear macrophage leukemia cell lines RAW264.7, compared with a traditional ELISA method, the efficiency is improved by 10 times, the cost is reduced, and the kit has the remarkable advantages of being high in throughput, wide in linear range and high in stability.

A cell processing platform and method for selecting and isolating target cells, such as T-cells, NK-cells, or hematopoietic stem cells, from a biological sample using functionalized microbubbles. The platform employs microbubbles with lipid shells, functionalized with streptavidin and biotinylated linkers, to bind specific target cells and render them buoyant within the suspension. A centrifugation module separates non-target cells by sedimentation while maintaining the buoyancy of target cell-microbubble complexes. A pneumatic control system disrupts the microbubbles under controlled pressure or frequency, releasing the target cells for downstream processing without compromising viability. Additional features include a microbubble generation module capable of sequentially functionalizing ligands for multi-step cell selection and a temperature-controlled environment to ensure ligand stability. The system supports non-destructive cell release and sorting, enabling precise, contamination-free, and high-efficiency cell isolation for therapeutic and research applications.

The present invention relates to a composition, a kit and a detection method for detecting hydrogen peroxide on the basis of self-biotinylation according to the peroxidation activity of a guanine quadruplex, and, more specifically, to a composition, a kit and a detection method for detecting hydrogen peroxide, the composition comprising: i) a guanine quadruplex-hemin complex (G-quadruplex-hemin complex); ii) biotinyl tyramide; and iii) a probe capable of binding to the guanine quadruplex.

This invention discloses a homogeneous microsphere based on singlet oxygen self-circulating aggregation-induced emission, its preparation, and a wash-free detection method, which improves the sensitivity and efficiency of wash-free luminescent oxygen channel immunoassay. This invention successfully prepared AIE receptor microspheres by embedding the photosensitizer AIER dye, ultra-bright AIEG dye, and singlet oxygen-responsive dye SO into carboxyl-modified polystyrene nanoparticles. Simultaneously, an antibody-1-labeled AIE receptor microsphere solution, an antigen-containing test solution, and biotinylated antibody-2 were added to a 96-well plate, followed by streptavidin-modified donor microspheres. After wash-free incubation, the fluorescence signal value was measured, and the concentration of antigen in the test solution was obtained according to a standard curve. This platform completes wash-free, highly sensitive detection within 5 minutes, innovatively combining the aggregation-induced emission characteristics of AIEgens and a singlet oxygen cycling strategy, providing an efficient and universal solution for wash-free diagnostics.

The invention belongs to the technical field of biological detection and analysis, and particularly relates to a high-fidelity biotinylation probe as well as a preparation method and application thereof in polysulfide detection. Specifically, the invention develops a novel biotinylation probe HPB, and the probe is formed by coupling HPE-IAM and biotin. Experimental results show that HPB is superior to IAB and other traditional reagents in the aspects of maintaining and efficiently labeling polysulfide, and a high-specificity solution is provided for Pr-SnH analysis at the proteomics level. By optimizing a marking scheme and introducing a precipitation-redissolution step, the detection accuracy of the polysulfide modified protein is further improved, so that a reliable tool is provided for protein polysulfide modification detection research under a complex cell background, and the method has a good practical application value.

Disclosed herein are chromatographic materials comprising crosslinked streptavidin molecules. The crosslinked streptavidin chromatographic materials may be used to prepare affinity chromatographic materials using biotinylated affinity agents, such as a biotinylated antibody, biotinylated antigen-binding fragment, or biotinylated oligonucleotide. Due to the crosslinked nature of the streptavidin molecules, the materials provided herein have reduced to no streptavidin leachate, resulting in improved performance.

The invention relates to the technical field of reagent preservation, in particular to biotinylated tyrosine phosphatase antigen preservation liquid as well as a preparation method and application thereof. The pH value of the biotinylated tyrosine phosphatase antigen preserving fluid is 7.0-7.5, and the biotinylated tyrosine phosphatase antigen preserving fluid is prepared from the following raw material components: a buffering agent, soluble metal salt, an organic dispersing agent, poly (ethylene glycol)-block-poly (propylene glycol)-block-poly (ethylene glycol) 8400, a metal ion complexing agent, bovine serum albumin, a protein protective agent and a preservative. By optimizing the components of the biotinylated tyrosine phosphatase antigen preserving fluid, when the prepared antigen preserving fluid is used for preserving a biotin-labeled tyrosine phosphatase antigen, the storage life is greatly prolonged under the condition of 2-8 DEG C. The biotinylated tyrosine phosphatase antigen preserving fluid prepared by the method is convenient to use, stable to store, economical and practical, and simple to prepare.

The invention belongs to the technical field of microbial nucleic acid detection and bioluminescence analysis, and discloses a bioluminescence nucleic acid detection method and kit based on DNA-RNA hybrid specific recognition. The kit comprises a streptavidin coated solid phase carrier, a biotinylated DNA capture probe, a signal enhancement DNA, a luminescence report fusion protein and a luminescence substrate thereof, the luminescent reporter fusion protein comprises a DNA-RNA hybrid binding domain and a luminescent enzyme domain. According to the method, target RNA is captured through a solid phase, a DNA-RNA hybrid is formed, the luminous report fusion protein is specifically combined with the DNA-RNA hybrid, a bioluminescence signal is generated after a luminous substrate is added, and the target RNA is detected. In the embodiment, an amplification step is not adopted, so that the method has the advantages of simplicity and convenience in operation, rapidness in detection, lower background and better specificity, and can be used for rapid detection of microorganisms.

The invention discloses a method for efficiently preparing fixed-point biotinylation recombinant protein in escherichia coli, and belongs to the technical field of biology. According to the invention, a weakened expression regulatory sequence regulates and encodes a biotin ligase (BirA) gene expression cassette and a target protein gene expression cassette encoding a sequence carrying a biotin receptor peptide tag (AVI-Tag) to be jointly constructed on an escherichia coli expression vector, so that efficient fixed-point biotinylation of a target protein in an escherichia coli body is realized. The method has the advantages of high biotinylation efficiency, high specificity, simplicity and convenience in operation and the like, can be widely applied to the fields of separation and purification of proteins, protein interaction research and the like, and has important practical application value.

The invention provides a mass spectrometric detection method and a WB identification method of over-sulfuration modified vegetable protein. According to the mass spectrometry detection method, N-ethyl maleimide dipolyethylene glycol biotin ester is used for selectively capturing and labeling sulfydryl and sulfhydryl of cysteine in a plant proteome, and then a streptavidin purification medium is used for enriching biotinylated polypeptide after enzymolysis; and finally, eluting the vulcanized protein peptide fragment through DTT or TCEP, carrying out LC-MS pretreatment on the eluted sample before loading, and loading the sample on a machine. In order to carry out visual analysis on the oversulfurized protein identified by mass spectrometry, a WB identification method is provided, related protein is subjected to in-vitro expression and purification, the protein is subjected to in-vitro oversulfurization treatment, then mercapto groups and thiomercapto groups of all cysteine are sealed by virtue of NEM, and the detection result is accurate. Then N-ethyl maleimide dipolyethylene glycol biotin ester is used for marking the protein reduced by TCEP, and the marked sample can be verified through a WB experimental method.

The invention relates to ribozyme for labeling biotin on target RNA (Ribonucleic Acid) as well as a screening method and application thereof. The RNA labeling technology is one of core tools for modern molecular biology research and clinical diagnosis. A specific marker is covalently linked to a target RNA molecule, so that accurate tracking, efficient detection and functional analysis of RNA can be realized. A biotin-streptavidin system becomes one of the technical routes which are most widely applied due to extremely high affinity and signal amplification capability of the biotin-streptavidin system. At present, common biotin-labeled RNA technical methods mainly comprise a chemical solid-phase synthesis method, an enzymatic method and a chemical labeling method. However, the methods have the limitations of poor site specificity, low efficiency, complex manipulation and the like in the use process. The engineering ribozyme for catalyzing RNA biotinylation is obtained by taking 12: 0 biotin coenzyme A as a biotin donor through an in-vitro screening technology. The ribozyme provided by the invention can efficiently and specifically carry out biotin labeling on target RNA, the reaction process is simple, and the labeling activity is up to 90% or above.

The invention discloses an engineered exosome preparation with tumor targeting and specific gripper response release functions as well as a preparation method and application of the engineered exosome preparation. The preparation comprises a myocardial cell exosome, an NK cell biotinylation activation antibody, a tumor disease biotinylation antibody, streptavidin, a tumor fiber matrix FAP targeting peptide and a tumor matrix enzyme response peptide, and anchoring is carried out through an acetamide compound-polyethylene glycol anchor point platform. The engineering bispecific exosome preparation with good tumor targeting and barrier breakthrough ability and immune cell activation effect is prepared, and the preparation breaks a solid tumor compact fiber barrier and increases NK cell infiltration by utilizing the fibrosis treatment ability of the myocardial cell exosome and the capture and targeting effects of an anchor point platform; the natural killer cells are in close contact with tumor cells, the lasting tumor cell killing effect is achieved, and the tumor matrix environment is fundamentally changed.

According to the oligonucleotide functionalized gold nanoparticle-based multiple lateral chromatography biological detection system and method provided by the invention, high-sensitivity and programmable nucleic acid target detection is realized through functionalized combination of gold nanoparticles and multiple oligonucleotide probes. The system of the invention comprises: 1) a tunable oligonucleotide-AuNP conjugate (each AuNP is linked to 2-3 thiolated probes); 2) a standardized test strip (containing a streptavidin detection line and an ACTB-828 quality inspection line); and 3) a sandwich hybridization mechanism (the target nucleic acid is combined with the AuNP probe and the biotinylation report oligonucleotide at the same time). The method has the beneficial effects that (1) due to the target-induced plasma aggregation effect, an optical signal is enhanced through AuNP close-range aggregation; and (2) a general test paper structure can adapt to a new target only by adjusting a probe sequence. Experiments show that the detection limit reaches 50 pM, and the room temperature stability is gt; the method is suitable for the fields of rapid pathogen detection, on-site diagnosis and the like.

Herein is reported a method for producing C-terminally biotinylated FcRn comprising the steps of cultivating a mammalian cell comprising a deoxyribonucleic acid encoding FcRn and E. coli biotin-[acetyl-CoA-carboxylase] ligase (BirA) in a biotin containing medium, and recovering C-terminally biotinylated FcRn from the cell or the cultivation medium, wherein the deoxyribonucleic acid encoding FcRn and E. coli BirA is stably integrated into the genome of the mammalian cell and comprises in 5′- to 3′-direction a first expression cassette encoding class I major histocompatibility complex-like protein (α-FcRn) comprising a HisAvi-tag at the C-terminus, a second expression cassette encoding β2-microglobulin (β2m), a third expression cassette encoding class I major histocompatibility complex-like protein (α-FcRn) comprising a HisAvi-tag at the C-terminus, a fourth expression cassette encoding β2-microglobulin (β2m), and a fifth expression cassette encoding E. coli biotin-[acetyl-CoA-carboxylase] ligase.

The invention relates to a rapid detection method for cadmium residual quantity in aquatic products based on magnetic qualitative separation and polarized light distinguishing and quantifying. The method comprises the following steps: coupling a biotinylated cadmium monoclonal antibody through streptavidin magnetic microspheres, and specifically enriching trace cadmium in the aquatic product digestive juice to form a magnetic compound; a muller matrix microscope is used for collecting a polarization microscopic image of a compound, and a deep learning model (such as RESNET34) is combined to carry out binary classification and particle counting on the image, so that rapid and high-sensitivity quantitative detection of cadmium can be realized. The method is easy and convenient to operate, the target object magnetic separation time is within 2 min, the particle distinguishing accuracy rate is higher than 84%, the quantitative correlation Rreaches 0.9 or above, and the method is suitable for rapid monitoring of trace cadmium (several micrograms / L) in aquatic products.

The invention relates to the technical field of protein detection, in particular to a detection method and a kit for detecting an anti-Nephrin antibody. The detection method comprises the following steps: capturing an anti-Nephrin antibody in a sample to be detected on an SA matrix by adopting biotinylated Nephrin protein to obtain a first compound; carrying out acidolysis desorption and neutralization on the first compound, and directionally fixing an antibody by Protein G to obtain a second compound; aiming at the second compound, detecting by adopting a biotin-streptavidin-HRP (Horse Radical Polymorphism) system; the acidolysis desorption comprises the following steps: treating the first compound for 10-20 minutes by adopting an acid solution with the pH value of 2-3 under the conditions that the temperature is 35-40 DEG C and the speed is 500-800 rpm. The method provided by the invention can accurately and quickly detect the level of the anti-Nephrin antibody in the sample, and has important application value.

The invention provides a UBC-CK8 / 18 detection kit based on chemiluminescence, and the kit is characterized in that an antibody is immobilized through a streptavidin-biotin system to form a magnetic bead-biotinylated antibody-antigen-acridinium ester labeled antibody compound; after washing, the substrate solution excites the acridinium ester to generate a photon signal, and a relative luminescence unit (RLUs) is captured by a full-automatic chemiluminescence immunoassay instrument, so that rapid and low-cost clinical detection of bladder cancer is realized, and the detection performance is good.

Methods are provided to capture telomere-associated DNA loci from chromatin. Chromatin was prepared from cultured cells by dual crosslinking using formaldehyde and EGS, followed by sonication. Biotinylated PNA probes were hybridized to the telomere DNA sequences, and serine protease was used to release the telomere-associated DNA sequences. The released DNA fragments in the supernatant were purified and subjected to library preparation for next-generation sequencing. The ligation-free chromatin capture and sequencing method enriches specific telomere-associated DNA loci to provide an accurate representation of chromatin interaction. Insights into the chromatin interactions occurring at telomeres are used to investigate the potential role of telomers in aging and age-related diseases.

The invention relates to the technical field of biology, in particular to antigen preserving fluid and a preparation method and application thereof. The invention provides an antigen preservation solution and a preparation method thereof, the antigen preservation solution adopts a sodium tetraborate buffer solution, and potassium chloride, glycerol, bovine serum albumin, triton, ADP, ProClin300 and methylisothiazolinone are added as an inorganic salt, a stabilizer, an excipient, a surfactant, a protein protective agent and a preservative respectively. A stable preservation environment is provided for the biotinylated U1RNP antigen, the problems that the biotinylated U1RNP antigen is prone to dissociation and degradation, consequently, the biotinylated U1RNP antigen cannot be stably preserved, and inconvenience is brought to transportation and use are solved, and the problems that an anti-U1RNP antibody IgG detection kit is poor in carrier stability and real-time stability are further solved.

Disclosed herein are chromatographic materials comprising streptavidin molecules, wherein the streptavidin molecules are bound to biotin and one or more biotinylated affinity agents. The biotinylated affinity agent may be a biotinylated antibody, biotinylated antigen-binding fragment, or biotinylated oligonucleotide. The streptavidin chromatographic materials may be used to prepare affinity chromatographic materials. Due to biotin binding to the conjugated streptavidin, the materials provided herein have reduced to no streptavidin leachate, resulting in improved performance.

A cell selection chamber includes an inlet and an outlet, with a reservoir positioned therebetween and configured to allow for fluid flow from the inlet to the outlet. The reservoir contains a plurality of microbubbles, which are each at least partially coated with streptavidin. An upstream membrane is positioned between the inlet and the reservoir, while a downstream membrane is positioned between the outlet and the reservoir. The membranes include a plurality of pores each having a diameter that is less than a diameter of the microbubbles. In use, a heterogeneous population of cells is mixed with a biotinylated antibody additive and then conveyed into the cell selection chamber so as to cause target cells of the heterogeneous population of cells to become bound to the microbubbles and to cause other cells of the heterogeneous population of cells to flow out of the cell selection chamber as unbound cells.

The invention relates to a method for marking neurons and application of the neurons to unicellular reconstruction of the neurons. The method comprises the following steps: expressing a proximity marker enzyme with enhanced solubility in a target neuron, and providing biotin to the target neuron so as to form biotinylated protein in the neuron; carrying out integral sample dyeing on the biotinylated protein by using monovalent streptavidin coupled with a detectable marker; imaging the dyed sample to obtain a neuron structure image; and reconstructing the morphological structure of the single neuron based on the image data.

The invention discloses a mutant gene enrichment method, a mutant gene detection method and a mutant gene detection kit based on Cas9 specific cleavage and isonucleotide magnetic beads. The method comprises the following steps: firstly, extracting free DNA; then identifying and cutting a completely matched wild type sequence by using Cas9 protein and specific sgRNA, and reserving the mutant DNA due to base mismatch; cas9 treated DNA and streptavidin magnetic beads containing a biotinylated oligonucleotide probe are incubated, guanine and cytosine in the probe are substituted by isoguanine and isocytosine respectively, and adenine and thymine are modified by locked nucleic acid, so that high-stability homodromous pairing is realized, and mutation DNA is selectively enriched; and finally, carrying out qPCR or sequencing detection on the enriched DNA. The kit has the characteristics of simplicity and convenience in operation, high specificity and high sensitivity, can be used for detecting single-base-level mutation, and is suitable for liquid biopsy, tumor early screening and genetic disease mutation detection.