34 results about "Avidin" patented technology

A kind of biotin or avidin labeled fat body and its preparation method, nano-carrier system. Biotin or avidin labeled fat body is prepared using specific amount of Bio-phospholipid or avidin-phospholipid, and the prepared fat body has the advantages of high purity, small particle size, good uniformity and high stability. Based on the biotin-avidin system, a nano-carrier system is constructed, which includes the biotin labeled fat body and the avidin modified target component. The system enables the fat body to carry any interested substance, such as viral recombinant protein, antibody and other protein drugs, nucleic acid drugs or small molecule drugs, etc., so as to be used for the treatment of diseases such as vaccines, cancer, infectious diseases and metabolic diseases.

This invention relates to an alanine aminotransferase (ALT) detection reagent and its preparation method, belonging to the field of medical testing. The ALT detection reagent comprises nanobodies AC1 and AT1 binding to different ALT binding sites. Nanobodies AC1 are biotinylated and immobilized on an avidin ELISA plate as a capture antibody, while nanobodies AT1 serve as the detection antibody. The ALT detection reagent and method prepared based on these nanobodies can meet the needs for rapid and accurate ALT detection.

This work proposes a novel enzyme-free electrochemiluminescence sensing platform based on novel DNA-quantum dot nanostructures and hybridization chain reaction (HCR) amplification, and applies it to trace Cd. 2+ The detection; first, Cd 2+ Aptamer-triggered HCR amplification introduces a large amount of biotin-labeled DNA into the electrode, whereby biotin specifically captures a large amount of avidin SA-CdS quantum dot complexes, exhibiting a high ECL signal; target Cd 2+ Upon binding to its aptamer, the quantum dot-DNA structure detaches from the electrode, resulting in a significant decrease in the ECL signal, thus enabling the control of Cd. 2+ This sensor exhibits ultrasensitive detection with a dynamic response range from 10 fM to 10 nM and a detection limit of 2.6 fM. It demonstrates excellent selectivity, speed, high sensitivity, and practicality for detecting real water samples, providing a novel and competitive strategy for detecting heavy metal ions in real-world samples.

The present invention belongs to the technical field of genetic engineering, and specifically relates to a copepod luciferase mutant and the use thereof. The mutant is obtained by means of performing one or more mutations on a wild-type copepod luciferase with the signal peptide removed, and can be expressed in a prokaryotic expression system, resulting in an increased luminescence half-life or a signal rise within a certain time range, and the luminescence pattern of the luciferase is converted to glow-type luminescence or luminescence with a sustained increase in luminescence intensity. Some copepod luciferase mutants exhibit enhanced luminescence intensity. The mutant is widely used in biological research for real-time tracking and continuous monitoring, such as for labeling and tracking activities or processes in living organisms. On the basis of the advantage of increased luminescence half-life of the copepod luciferase mutant, the mutant can be used as and / or in the preparation of a glow-type luciferase. The copepod luciferase mutant is more suitable as a reporter gene for in-vivo detection in scientific research, and is conjugated with avidin, a digoxin antibody, etc., for sequencing, thereby shortening the sequencing time and improving the sequencing quality.

The application provides a detection kit for a novel coronavirus antigen, comprising a capture antibody, a biotin-labeled detection antibody, a SARS-CoV2 N protein standard sample, an enzyme-labeled avidin, a chromogenic solution and a termination solution, wherein the capture antibody comprises an anti-SARS-CoV2 N protein capture antibody, the sequence of the heavy chain variable region of the anti-SARS-CoV2 N protein capture antibody comprises an amino acid sequence as shown in SEQ ID NO:1, and the sequence of the light chain variable region comprises an amino acid sequence as shown in SEQ ID NO:2. The detection kit can qualitatively and quantitatively detect the novel coronavirus, has a low detection limit and a wide linear range, can accurately and efficiently detect the novel coronavirus in an early stage, and is beneficial to the prevention and control of the novel coronavirus pneumonia.

The application belongs to the technical field of biological detection, and particularly relates to a monoclonal antibody combination for detecting human pregnancy-associated plasma protein A and application thereof. The combination comprises monoclonal antibodies 4H5 and 1G8, and CDR amino acid sequences of heavy chain and light chain variable regions of the antibodies are shown in SEQ ID NO. 1-SEQ ID NO. 12. The combination can be used to construct a double antibody sandwich ELISA detection system, 4H5 is used as a coating antibody, 1G8 is biotin-labeled, signal amplification is realized by combining biotin-avidin, and the detection sensitivity is significantly improved. The method can effectively distinguish serum samples of patients with acute coronary syndrome and healthy people, and is suitable for rapid and sensitive detection of biomarkers related to cardiovascular diseases in primary clinical practice.

The invention relates to a heparin anticoagulant pentasaccharide capable of neutralizing and adjusting half-life period as well as a preparation method and application of the heparin anticoagulant pentasaccharide. Comprising the following steps: (1) preparing heparin hexasaccharide; (2) preparing heparin anticoagulant hexasaccharide; and (3) preparing the heparin anticoagulant pentasaccharide capable of neutralizing and adjusting the half-life period. The heparin anticoagulant pentasaccharide provided by the invention is structurally similar to the unique ultra-low molecular weight heparin fondaparinux sodium in the current market, a biotin group is only introduced to an E glycosyl group at a non-reducing end, so that rapid neutralization can be effectively realized through avidin, and by introducing PEG (Polyethylene Glycol) connexons with different lengths, the heparin anticoagulant pentasaccharide can be rapidly neutralized. The prepared heparin anticoagulant pentasaccharide can adjust the half-life period of ultra-low molecular weight heparin. Therefore, the lasting time of the medicine effect of the ultra-low molecular weight heparin is prolonged, and the requirement of frequent administration is reduced. Therefore, the anticoagulant effect of the ultra-low molecular weight heparin is more controllable, the treatment risk is reduced, and the treatment effect is improved.

The invention discloses a phage multifunctional affinity interface as well as a preparation method and application thereof, and belongs to the field of functional biological materials. The preparation method of the phage multifunctional affinity interface comprises the following steps: modifying a phenylboronic acid group by using pVIII protein on the side wall of an M13 phage as a bracket; connecting histidine on the protein of the M13 bacteriophage pIII to the nickel magnetic microbead; the method comprises the following steps: carrying out fluorescence labeling on a biotinylated aptamer targeting EpCAM positive cells, hybridizing with a complementary chain of a labeled fluorescence quencher, and coupling with avidin according to a molar ratio of 4: 1 to obtain an avidin-biotinylated DNA switch; and then the M13 bacteriophage-nickel magnetic microbead containing the phenylboronic acid group is coupled with an avidin-biotinylated DNA (Deoxyribose Nucleic Acid) switch. The capture efficiency of the multifunctional affinity interface to MCF-7 cells reaches 94.2%, the release efficiency reaches 92.7%, and the multifunctional affinity interface has reproducibility and can be used for multiple rounds of cell separation.

The application relates to a protein sample processing method, comprising the following steps: mixing a protein sample with an alkylating agent to seal free cysteine, obtaining a sealed sample; centrifuging the sealed sample through an ultrafiltration membrane, obtaining a membrane sample; the pore size of the ultrafiltration membrane ranges from 10 kDa to 30 kDa; performing first reduction on the membrane sample, obtaining a first reduced sample; adding a biotin labeling agent to the first reduced sample, obtaining a labeled sample; enzymatically digesting the labeled sample, obtaining an enzymatically digested sample; adding avidin microbead agarose to the enzymatically digested sample to adsorb biotin-labeled proteins, obtaining an enriched sample; performing reduction and alkylization on the enriched sample, obtaining a processed sample.

The application discloses a platelet antibody detection and cross matching blocking chromatography kit and a detection method thereof, wherein the kit comprises a U-shaped microwell plate, a chromatography medium for separating platelet immune complexes from non-cell particle components under the action of centrifugal force, freeze-dried platelets, a platelet diluent, a platelet fluorescent staining solution comprising fluoresceinized platelet antibodies specifically labeled for platelets, biotin-labeled anti-human globulin for specifically binding with antibodies bound to the surface of the platelets, avidinized fluorescein for coupling with the biotin-labeled anti-human globulin through a biotin-avidin specific binding system, negative control serum / plasma and positive control serum / plasma. The application combines the blocking chromatography technology with a high-sensitivity flow immunofluorescence method to construct an efficient and accurate platelet antibody detection and cross matching system, which is high in specificity and sensitivity, simple in operation and stable in detection results.

The invention provides a nucleic acid nanoprobe for detecting signal amplification of A [beta] O, comprising: a signal output unit QDs, which is a CdSe / ZnS quantum dot modified by surface modification streptavidin synthesized by a thermosol method; the metal organic framework MOFs is synthesized by taking a metal ion Zr as a center and porphyrin as an organic ligand through a hydrothermal method, and is used as a carrier and a quencher of the CdSe / ZnS quantum dots at the same time; an Aptamer sequence of A [beta] O; the DNA1 sequence is designed according to the AbetaO Aptamer sequence and is complementary to the AbetaO Aptamer sequence, the 5'end of the DNA1 sequence is modified with a phosphorylation group, and the 3 'end of the DNA1 sequence is modified with avidin; stability is good, cost is low and sensitivity is high. The invention also provides a preparation method of the nucleic acid nanoprobe for detecting signal amplification of AbetaO. According to the present invention, the AbetaO in the peripheral blood is quantitatively detected, and the new thought and the new means can be provided for the early diagnosis of the Alzheimer's disease.

The invention belongs to the technical field of detection, and particularly relates to a method for detecting non-protein small molecules and application, the method comprises the following steps: providing functional microspheres, the functional microspheres comprise microspheres, molecular arms and non-protein small molecules, the non-protein small molecules are combined to the microspheres through the molecular arms, and optionally, the non-protein small molecules are combined to the microspheres through the molecular arms; the molecular arm is connected with the microsphere through an avidin ligand; performing a competitive reaction on an object to be detected, the non-protein small molecules combined on the functionalized microspheres and a quantum dot labeled detection antibody, and forming a microsphere array by the functionalized microspheres before or after the competitive reaction; and detecting quantum dot signals in the microsphere array, and obtaining the concentration and / or content of the non-protein small molecules in the to-be-detected object based on a detection result. The method provided by the invention is beneficial to reducing the detection limit and / or shortening the detection time.

This invention provides an electrochemical sensor for detecting PDGF-BB using a poly A-DNA tetrahedral probe and its application. The electrochemical sensor is a base-stack-dependent electrochemical sensor, comprising a poly A-tetrahedral probe self-assembled on a gold electrode, aptamer DNA, horseradish peroxidase, and a chromogenic substrate. The aptamer DNA is biotin-modified at its tail, and the horseradish peroxidase is avidin-modified. The electrochemical sensor detects PDGF-BB. The aptamer DNA is triggered by PDGF-BB to transform into a stem-loop structure and stacks with the poly A-tetrahedral probe. Based on the base stacking effect, the aptamer DNA stably hybridizes with the target complementary sequence of the poly A-tetrahedral probe immobilized on the gold electrode. The aptamer DNA and horseradish peroxidase bind via biotin-avidin. The chromogenic substrate is catalyzed to generate an electrochemical redox catalytic signal, which is then output.

The invention belongs to the technical field of biological detection, and particularly relates to a monoclonal antibody combination for detecting human pregnancy-related plasma protein A and application of the monoclonal antibody combination. The combination comprises monoclonal antibodies 4H5 and 1G8, and CDR amino acid sequences of heavy chain and light chain variable regions of the monoclonal antibodies 4H5 and 1G8 are as shown in SEQ ID NO.1-SEQ ID NO.12. The combination can be used for constructing a double-antibody sandwich ELISA detection system, 4H5 is used as a coating antibody, 1G8 is used for biotin labeling, signal amplification is achieved by combining biotin-avidin, the detection sensitivity is remarkably improved, the method can effectively distinguish serum samples of acute coronary syndrome patients and healthy people, and the detection accuracy is improved. The method is suitable for rapid and sensitive detection of cardiovascular disease related biomarkers in basic clinical application.

The present disclosure relates to non-porous polymer particles having an average particle size of from 1 micron to 10 microns and functionalized with a Streptomycete avidin. Streptomycete avidin functionalized particles of the present disclosure can be bound to a biotinylated antibody, a biotinylated antigen binding fragment or a biotinylated oligonucleotide thereof to produce a customizable affinity chromatography column. That is, functionalized non-porous polymer particles may be filled in a stainless steel, titanium, or other metal or metal alloy column for affinity high pressure liquid chromatography (HPLC).

This invention discloses a porcine Fab antibody against Seneca virus A (SVA) and its competitive ELISA detection method. The amino acid sequences of the heavy and light chain variable regions of the neutralizing Fab genetically engineered antibody are shown in SEQ ID No. 4 and SEQ ID No. 7. The antibody exhibits high affinity for SVA. A competitive ELISA detection method was established, determining the optimal SVA particle coating concentration to be 1 μg / mL, the optimal working concentration of the competitive antibody to be 0.5 μg / mL, the optimal dilution ratio of the serum sample to be tested to be 1:10, and the optimal dilution ratio of the enzyme-labeled avidin to be 1:30000. The highest sensitivity and specificity (96.88% and 100%, respectively) were achieved when the inhibition percentage (PI) was 47%, and the antibody did not react with positive sera from common major porcine viral diseases. The intra-assay coefficient of variation ranged from 1.12% to 7.34%, and the inter-assay coefficient of variation ranged from 1.19% to 11.72%, indicating good reproducibility. This method and VNT detection were used to simultaneously detect 224 clinical porcine serum samples, with a concordance rate of 93.75%.

The application discloses a SP10 / ACP / PSA triple detection test strip and a preparation process thereof, wherein a nitrocellulose membrane in the test strip is provided with a first detection line T1, a second detection line T2, a third detection line T3 and a quality control line C; the first detection line T1 is marked with SP10 monoclonal antibody 1; the second detection line T2 is marked with ACP monoclonal antibody 1; the third detection line T3 is marked with PSA monoclonal antibody 1; the quality control line C is marked with avidin SA; and the combination pad is provided with quantum dot microspheres marked with SP10 monoclonal antibody 2, ACP monoclonal antibody 2 and PSA monoclonal antibody 2; the test strip can simultaneously detect three indexes, and has simple product structure and convenient operation; the marking process in the preparation process adopts a competitive inhibitor and a quencher, solves the hook effect, and simultaneously obviously improves the specificity of each index.

The invention provides a multiple miRNA detection electrochemical biosensor, a preparation method, a product and application, and belongs to the technical field of electrochemical detection. The multiple miRNA detection electrochemical biosensor is developed on the basis of an amino-functionalized nano material or a modified avidin nano material, and a specific capture probe and a signal probe marked with different metal ions or biotin are designed; by combining electrochemical detection methods such as two-step sandwich type hybridization reaction and differential pulse voltammetry or square wave voltammetry, quantitative simultaneous detection of multiple miRNAs is realized, the detection process is simplified, the detection efficiency is improved, and the problem that multiple markers cannot be simultaneously detected by a traditional method is solved. In addition, by optimizing hybridization reaction conditions and probe design, the specificity of the sensor is improved, cross reaction is reduced, meanwhile, the stability and reproducibility of detection results are guaranteed, and finally an efficient and accurate tool is provided for clinical detection of miRNA.

To provide compounds that are useful for delivering therapeutic, diagnostic, and imaging agents, to provide pharmaceutical compositions containing such compounds and methods of using the compounds and compositions, and to provide processes for manufacture of the compounds and the compositions containing the same.SOLUTION: Provided are compounds that are selective for cancer cells, are quickly bound to or are internalized into those cells and are quickly localized into appropriate compartments in the cell where the compounds can exact their greatest therapeutic effect in a patient specific fashion. In one aspect, provided is a compound of Formula (I): A-L1-G1-Q-G2(I), where A comprises at least one avidin-type molecule, each avidin-type molecule comprising 1 to 4 monomer units, L1 is a linker group, G1 is a forward primer binding site, Q is randomized single-stranded DNA, and G2 is a reverse primer binding site.SELECTED DRAWING: Figure 1

Methods, assays, systems, and kits for determining the presence, severity, and / or susceptibility of heart failure (HF) in an individual are disclosed. The methods utilize a solid matrix in which streptavidin-coated particles are pre-incubated with a biotinylated antibody to form a solid phase reagent. Since the solid phase reagent is now present in a pre-complex form with the biotinylated antibody, there is less opportunity for biotin from the sample to interfere with the assay. The methods, systems, assays, and kits of the present disclosure allow NT-proBNP assays to demonstrate no biotin interference at concentrations of up to 3510 ng / mL biotin.

This application relates to a method and its application for improving the detection signal value of photo-induced chemiluminescence (PET). The method includes: mixing a companion reagent with antibody-coated luminescent microparticles, antibody-coated biotin, avidin-coated photosensitive microparticles, and a sample to be tested, reacting the mixture to generate a test mixture; exciting the test mixture at least once with excitation light, and measuring the amount of emitted photons to obtain a light signal value; wherein the companion reagent includes an oxygen-generating agent and a catalyst, the oxygen-generating agent undergoes a catalytic reaction under the action of the catalyst to generate oxygen, and the oxygen provides singlet oxygen for PET detection. The solution provided in this application can improve the detection signal value of PET, thereby enhancing the stability, sensitivity, and precision of the detection.

To provide means that enables measurement of L-biotin in a sample.SOLUTION: The above challenge is cleared by an L-biotin measurement reagent containing optically isomeric avidins and an azobenzene derivative represented by a formula (I) below. In the formula, each of R1 through R10 independently represents a hydrogen atom or a group selected from a group consisting of a hydroxy group, carboxy group, C1-C6 dialkylamino group having a non-substituent or substituent group, C1-C6 alkyl group having a non-substituent or substituent group, and C1-C6 alkoxy group having a non-substituent or substituent group, where at least one of R1 through R5 is a hydroxy group or C1-C6 dialkylamino group having a non-substituent or substituent group, and at least one of R6 through R10 is a carboxy group.SELECTED DRAWING: Figure 2

This invention belongs to the field of biodetection technology, specifically relating to a monoclonal antibody combination for the detection of NfL protein and its application. The combination comprises monoclonal antibodies 9E1 and 10B4, whose complementary determinant amino acid sequences of the heavy and light chain variable regions are shown in SEQ ID NO. 1-12, respectively. The antibody combination can be used to construct a double-antibody sandwich ELISA detection system, particularly suitable for use with a biotin-avidin signal amplification system to achieve highly sensitive and specific detection of NfL protein, with a detection sensitivity of up to 20 pg / mL. This method is low-cost, simple to operate, and suitable for the quantitative analysis of NfL protein in serum, plasma, and other samples.

This invention, entitled "An Improved Compatibility Post-Amplification Chemiluminescence Detection System and Its Applications and Products," belongs to the field of in vitro diagnostic technology. It aims to solve technical problems existing in current post-amplification chemiluminescence detection systems, such as insufficient signal amplification, high background signal, poor hardware compatibility, and easy distortion of antigens / antibodies. The post-amplification chemiluminescence detection system of this invention includes a magnetic bead working solution and a labeled working solution; the labeled working solution is composed of a biotinylated labeled carrier, a biotinylated targeting molecule, unmodified avidin, and unmodified biotin, with a molar ratio of (2.5-3.5):1.0:(1.0-2.0):4.0. This invention can achieve efficient multi-cascade signal amplification, reduce background signal and non-specific adsorption, avoid antigen / antibody distortion, is compatible with existing in vitro diagnostic hardware, significantly improves detection sensitivity and signal-to-noise ratio, and has strong universality, applicable to the detection of various antigens and antibodies.

The application discloses a method for combined analysis of high-sensitivity cardiac troponin and copeptin for non-diagnostic purposes, and belongs to the technical field of protein detection. The method comprises the following steps: separating a plasma sample through centrifugation, preparing a phosphate buffer for dilution, and preparing a sample for detection; constructing an immune analysis system on a multi-well plate by adopting a double-antibody sandwich method, sequentially performing coating, cleaning, blocking, and preparing a standard sample and a labeled antibody; adding the sample and the standard sample into a detection plate, sequentially performing incubation, adding a detection antibody, and adding enzyme-labeled avidin, and finally developing color and measuring absorbance; collecting detection data to establish a standard curve, calculating a sample concentration by using a double-index collaborative correction model, and performing cross-validation and abnormal value processing. According to the scheme, more stable quantitative results can be obtained, and the anti-interference capability of data detection is enhanced.

The application provides a fusion protein for antibody site-specific coupling and application thereof. The fusion protein of the application is mainly fused by an antibody Fc affinity protein binding monomer and an avidin protein, realizes direct coupling of the antibody Fc affinity protein and a biotin-labeled molecule, and no longer uses a click chemistry scheme, so that the production and use difficulty of the antibody Fc affinity protein Protein G is greatly simplified, the Protein G protein no longer needs to be activated through the click chemistry in the production, the transportation and storage conditions no longer need to be strictly controlled, and even one-step antibody molecule coupling can be realized.

The application discloses a kind of base-removing endonuclease magnetic nano imprinting material and its preparation and application.First, avidin is covalently modified on the surface of magnetic nanoparticles, then biotin is combined to reach saturation state, then template molecule APE1 is combined and fixed, then phenylboronic acid derivative is added for modification, then dopamine is added for in-situ polymerization and surface imprinting, then two different molecular weight mPEG-NH2 are used to double close the surface, finally remove template molecule, obtain the magnetic nano imprinting material of APE1.The affinity and specificity of the magnetic nano imprinting material to APE1 and anti-interference ability have breakthrough progress compared with prior art, high-purity APE1 protein can be obtained from complex biological samples (including but not limited to living cells, cell extracts, exosome extracts, etc.) simply and quickly, in-situ capture and separation and purification of APE1 in living cells are realized, which is helpful for detailed and in-depth study on structural change and functional regulation of APE1 in living cells.

The invention relates to the technical field of in-vitro diagnosis, and particularly discloses a coupling process for preventing avidin from falling off and improving stability of avidin magnetic beads. The invention discloses a coupling process for preventing avidin from falling off and improving stability of avidin magnetic beads. The coupling process comprises the following steps: pretreating the magnetic beads; performing activation reaction; coupling reaction: centrifugally separating the activated magnetic beads, removing supernate, adding a PBS (Phosphate Buffer Solution) containing avidin, incubating at constant temperature, and rotating and uniformly mixing during incubation to obtain a reaction system A; the sealing is stable; secondary cross-linking: carrying out centrifugal separation on the closed and stabilized reaction system B, removing supernate, washing magnetic beads by using a PBS buffer solution containing Tween-20, adding a PBS buffer solution containing BS3, and carrying out rotary incubation at room temperature for secondary cross-linking, so as to obtain a reaction system C; carrying out quenching reaction; and washing: washing the magnetic beads with a PBS buffer solution containing Tween-20, finally resuspending the magnetic beads with the same buffer solution, and adjusting the concentration to obtain the avidin magnetic beads.

The present invention relates to the technical field of genetic engineering, and in particular to a Copepod luciferase mutant and a use thereof. The mutant is obtained by performing one or more mutations on a wild-type Copepod luciferase from which a signal peptide has been removed, can be solubly expressed in a prokaryotic expression system and exhibits a reduced luminescence half-life, and some Copepod luciferase mutants show enhanced luminescence intensity. The Copepod luciferase mutant is widely used in terms of sequencing, non-diagnostic detection of target molecules, drug screening, life science research, environmental monitoring, serving as a reporter gene, etc. On the basis of the advantage of the reduced luminescence half-life exhibited by the Copepod luciferase mutant, the Copepod luciferase mutant can be used as and / or to prepare a flash-type luciferase; the Copepod luciferase mutant is more suitable as a reporter gene for use in promoter detection; and the Copepod luciferase mutant is conjugated with avidin, a digoxin antibody, etc., for sequencing, thereby shortening sequencing time and improving sequencing quality.

The invention belongs to the technical field of biological analysis and detection, and particularly relates to a composition, a detection reagent and a detection method for detecting an object to be detected. The invention firstly relates to a composition for detecting an object to be detected. The composition comprises a first aptamer coupled with a nucleic acid polymer, a second aptamer coupled with biotin, a carrier coupled with avidin or streptavidin and nucleic acid specific fluorescent dye.