429 results about "Affitin" patented technology

A fusion protein for delivery of a wide variety of agents to a cell via antibody-receptor-mediated endocytosis comprises a first segment and a second segment: the first segment comprising a variable region of an antibody that recognizes an antigen on the surface of a cell that after binding to the variable region of the antibody undergoes antibody-receptor-mediated endocytosis, and, optionally, further comprises at least one domain of a constant region of an antibody; and the second segment comprising a protein domain selected from the group consisting of avidin, an avidin mutein, a chemically modified avidin derivative, streptavidin, a streptavidin mutein, and a chemically modified streptavidin derivative. Typically, the antigen is a protein. Typically, the protein antigen on the surface of the cell is a receptor such as a transferrin receptor-or an insulin receptor. The invention also includes an antibody construct incorporating the fusion protein that is either a heavy chain or a light chain together with a complementary light chain or heavy chain to form an intact antibody molecule. The invention further includes targeting methods and screening methods.

The invention provides an ELISA kit for detecting titer of novel coronavirus neutralizing antibody. The kit comprises an elisa plate coated with biotin-streptavidin labeled human ACE2 protein, horseradish peroxidase labeled novel coronavirus RBD protein, a novel coronavirus neutralizing antibody positive control, a coating solution, a washing solution, a diluent, a confining solution, a developingsolution, a stop solution and the like. The kit has the characteristics of low cost, simple operation, high sensitivity, high specificity and high accuracy, and can be used for batch and rapid detection of novel coronavirus neutralizing antibodies.

The invention discloses a test strip for detecting aflatoxin B1 or M1 by utilizing an aptamer. The test strip for detecting the aflatoxin B1 or M1 by utilizing the aptamer, provided by the invention, comprises a sample absorption pad, a marker pad, a reaction film and a water absorption pad, wherein the marker pad is coated with a detection probe; the detection probe is an aflatoxin B1 aptamer marked by fluorescein; the nucleotide sequence of the aflatoxin B1 aptamer is sequence 1; the reaction film comprises a detection region and a quality control region; the detection region is coated with a conjugate formed by an aflatoxin B1 hapten and a carrier protein; and the quality control region is coated with a quality control probe, and the quality control probe is a conjugate formed by avidin conjugation probe marked aflatoxin B1 complementary single strand DNA (Deoxyribose Nucleic Acid)) molecules. The test strip for detecting the aflatoxin B1 or M1, provided by the invention, has the advantages of high sensitivity, accuracy in quantifying, strong specificity, simplicity and convenience, and short detection time.

The invention discloses an immunosensor based on hybrid chain reaction and single molecule counting. The immunosensor consists of a capturing antibody, a detection antibody, streptavidin, a biotinylated primer and a hairpin probe, wherein the capturing antibody is anti-TNF-alpha; the detection antibody is Bio-anti-TNF-alpha; a base sequence of the biotinylated primer (Bio-I) is 5'-AGT CTA GGA TTC GGC GTG GGT TAA TTT TTT TTT-biotin-3'; the hairpin probe consists of a hairpin probe H1 and a hairpin probe H2; a base sequence of the hairpin probe H1 is 5'-TTA ACC CAC GCC GAA TCC TAG ACT CAA AGT AGT CTA GGA TTC GGC GTG-3'; a base sequence of the hairpin probe H2 is 5'-AGT CTA GGA TTC GGC GTG GGT TAA CAC GCC GAA TCC TAG ACT ACT TTG-3'. The invention also provides a preparation method of the immunosensor and application of the immunosensor in detection of the TNF-alpha. The immunosensor disclosed by the invention has the advantages of high detection sensitivity, small sample use amount, no need of enzyme amplification and the like, and quantitative detection on low-concentration TNF-alpha can be realized.

The invention relates to the medical field of immunoassay, more specially, the invention provides a chemiluminescent immunoassay detection kit for phosphatidylinositol proteoglycan-3(GPC-3) and a preparation method thereof, and realizes the simultaneous serological detection of GPC-3 N terminal and C-terminal protein with the chemiluminescent immunoassay method. The kit has the advantages of simple sampling, convenient detection and accurate and specific technical method. The invention adopts a biotin-strapavidin system to coat antibodies and improve the efficiency of antibody coating and the linear range of detection as well as sensitivity, and can be conveniently used for the tracing observation of early diagnosis or treatment effect for primary carcinoma of liver.

The invention discloses a kit and a method for detecting a dermatophagoides pteronyssinus allergen specificity IgE antibody. The kit comprises a calibration material, a quality control material, a biotin-marked dermatophagoides pteronyssinus allergen solution, an alkaline phosphatase-marked mouse-antihuman IgE second antibody solution and a streptavidin-marked nanometer magnetic particle suspension liquid. The kit is utilized to detect the dermatophagoides pteronyssinus allergen specificity IgE antibody. In such a mode, all reagent components in the kit are excellent in stability; the period of validity can reach over one year; the detecting sensitivity is high, the peculiar performance is excellent and the variation is small; a perfect uniform technique is acquired through technical optimization in a large number of experiments; the production is performed in strict accordance with standard production operation specification and quality control regulation; a user can acquire a reliable result by only performing standard operation according to the operation specification; in the clinical research, the conforming relevance with a foreign imported reagent reaches up to over 90% and the cost of the kit is only 1/2 of the cost of the foreign imported reagent.

The invention provides a hepatic carcinoma targeted photo-thermal therapeutic agent as well as a preparation method and an application thereof and belongs to the field of biomedical engineering. The hepatic carcinoma targeted photo-thermal therapeutic agent is prepared with the method comprising the following steps: (1) preparing biotinylation nanometer microbubbles; (2) preparing a Cy7 fluorescently-labeled biotinylation anti-GPC3 (glypican3) antibody; (3) preparing biotinylation RGO (reduced graphene oxide); (4) coupling the products prepared in the step (1), step (2) and step (3) through a biotin-avidin system to obtain the hepatic carcinoma targeted photo-thermal therapeutic agent. The hepatic carcinoma targeted photo-thermal therapeutic agent has ultrasonic and fluorescence imaging functions, mediates RGO targeted delivery with an ultrasound-targeted microbubble destruction technology, monitors a photo-thermal therapeutic process in real time, can be used for preparing drugs for hepatic carcinoma therapy and has excellent clinical application value.

The invention discloses a sepsis early diagnosis liquid chip which mainly includes the following components: microsphere coated with PCT capturing antibody, microsphere coated with CRP capturing antibody, microsphere coated with IL-6 capturing antibody, microsphere coated with Neopterin capturing antibody, these microspheres have codes with different colors; biotin-labeled test antibody; avidin-linked phycoerythrin. The invention sepsis early diagnosis liquid chip has advantages of high detection efficiency, a small amount of sample, high specificity and high sensitivity. And at the same time, the invention can test four kinds of specific markers of sepsis simultaneously, improve sensitivity and specificity of sepsis early diagnosis, distinguish sepsis caused by bacterial and viral, judge severity and poor prognosis of sepsis and monitor continuously for judging reflection of patient to certain kind of treatment.

The invention relates to a double-antibody biotin-Avidin ELISA (enzyme-linked immuno sorbent assay) detection kit for cattle viral diarrhea virus antigen and an application method thereof. The kit comprises washing liquid for ELISA detection, developing liquid, stopping liquid, Streptavidin-HRP, positive control and negative control and is characterized by further comprising an ELISA plate coating cattle viral diarrhea virus single antibody 3D8 and a cattle viral diarrhea virus single antibody 3F9 marked by biotin. The detection without cross reaction is performed by using the kit, thereby being capable of preventing leak detection caused by low titer in the antibody and having high specificity; a biotin-affine sensitizer is used for amplification, thereby increasing the flexibility, improving the detection rate, and simultaneously reducing the amount of second antibody; and the kit is suitable for being used widely.

A microparticle immune chromatography of time-resolution fluorescence emulsion includes preparing biotinylation antibody and preparing immune time-resolution fluorescence microparticles, using Fusion 5 film to prepare avidin solid phase film detection line and quality control line by utilizing avidin to envelop said film, finally using double-antibody sandwich method to detect antigen quickly.

The invention relates to the medical field of immunoassay, particularly provides a measuring kit of the chemiluminescence immunoassay of a CA125 magnetic particle. The kit of the invention comprises: 1) a CA125 working calibrator; 2) the mixed solution of the magnetic particle coated with a CA125 monoclonal antibody and the CA125 monoclonal antibody marked by biotin; 3) streptavidin marked by horse radish peroxidase; 4) a chemiluminescence substrate; and 5) a reaction tube. Further, the method for preparing the kit according to the invention comprises the following steps: 1) the working calibrator is prepared by CA125 pure products; 2) the mixed solution of the magnetic particle coated with the monoclonal antibody and the monoclonal antibody marked by the biotin is prepared; 3) the horse radish peroxidase is used for marking the streptavidin; 4) the chemiluminescence substrate is prepared; 5) the working calibrator, the mixed solution, the enzyme markers, the chemiluminescence substrate and the reaction tube are sub-assembled; and 6) assembly is carried out to obtain a finished product. The kit of the invention has the advantages of simpleness and convenience, fastness, sensitivity and stability and the like.

The invention discloses novel coronavirus rapid detection test paper and a detection method. The novel coronavirus rapid detection test paper is composed of a sample pad, a colloidal gold pad, a reaction color development area, a water absorption area and a supporting plate; the sample pad and the water absorption pad are arranged on the supporting plate and located on the two opposite sides of the supporting plate respectively, and the sample pad is suction filter paper or a glass fiber membrane and used for bearing an object to be detected; a nitrocellulose membrane is fixed on the supporting plate, and the absorbent pad is absorbent paper; through double binding of a novel coronavirus antibody and a receptor ACE2 protein of a virus, a coronavirus protein antigen is specifically capturedand bound by adopting double enzyme-linked immunosorbent assay; the ACE2 antibody in the test paper reaction color development area is combined with biotin, avidin is connected with horse radish peroxidase, and through a biotin-avidin system, rapid judgment can be achieved through chemical color development, and the virus content can also be accurately detected through a microplate reader.

The invention relates to a novel magnetic molecular targeted ultrasound contrast agent, in particular to a gas-wrapped magnetic liposome microsphere suspension with the mean diameter of 1-4 micrometers and a preparation method thereof. The preparation method of the magnetic molecular targeted ultrasound contrast agent microsphere comprises a condition that a lipid layer of the microsphere and/or the surface of the lipid layer contains (or connects) magnetic response materials. A contrast agent microsphere wall material contains phospholipids, polyethylene glycol (PEG), PEG phospholipid polymers, biotinylated and/or polypeptide modificatory PEG phospholipid polymer, poloxamer, ligands (monoclonal antibodies or polypeptide, and the like) and the magnetic response materials and/or avidin bridging materials, wherein the ligand (monoclonal antibodies or polypeptide, and the like) has specific affinity to target molecules, the wrapped gas is a fluorine carbon gas, and a solvent is an aqueous medium (distilled water). The invention also provides the preparation method of the magnetic molecular targeted ultrasound contrast agent microsphere, which comprises a condition that the specific ligand is connected with the microsphere in a covalence and avidin bridging way. The novel magnetic molecular targeted ultrasound contrast agent has good targeted developing effect, can be used for evaluating the change of vessel endothelial molecules of an arterious and venous system of an organic tissue and has good application prospect in treatment.

The invention provides a visual detection method for mouse typhus salmonella based on aptamer recognition. The basic principle of the method is that the surface of a microwell plate is coated with avidin, sulfhydrylation salmonella aptamer which is marked by biotinylation salmonella aptamer and nanogold is adopted to recognize targeted salmonella, and on the basis, a silver enhancement technique is utilized to further amplify a detection signal, so that the visual detection is achieved. The visual detection method for the mouse typhus salmonella based on the aptamer recognition has the advantages of high specificity, strong sensitivity, simplification and rapidness, thereby providing the possibility for rapidly detecting the mouse typhus salmonella in an environment.

The invention provides an immune detection reagent for detecting respiratory syncytial virus and a corresponding reagent box. The immune detection reagent comprises anti-respiratory syncytial virus monoclonal antibody 1 as peridium antibody, anti-respiratory syncytial virus monoclonal antibody 2 as biotin labeling antibody and avidin-HRP (horseradish peroxidase). The invention also provides a method for detecting the respiratory syncytial virus by applying the immune detection reagent or the reagent box. The method has relatively high sensitivity and specificity and is easy to clinically use.

The invention relates to a microRNA (ribonucleic acid) detection probe and a method for detecting microRNA. The detection probe comprises three parts, an intermediate region is of single-stranded DNA (deoxyribonucleic acid) which is complementary to the microRNA, one end of the single-stranded DNA is connected with a DNA enzyme as a signal output part, and labeled biotin is arranged at the other end of the single-stranded DNA. The probe is added in a system to be detected, the single-stranded DNA of the probe and the target microRNA are complementary and paired, DSN (duplex-specific nuclease) selectively digests a DNA-RNA hybrid DNA chain, and the RNA can be recycled. Streptavidin magnetic beads are added, and the magnetic beads and the probe labeled by the non-reacted biotin are removed from a water solution through a ferromagnetic body. The part of the solution is still used for further signal output reaction. The detection method disclosed by the invention adopts DSN amplification and ribozyme amplification, and becomes a method for detecting the microRNA, which has the advantages of low background, high sensitivity and strong specificity.

The invention provides a chemiluminescent immunoassay kit for thyroid peroxidase autoantibodies and a preparation method thereof. The invention has the advantages that the reaction pattern of the double antigen sandwich method is adopted, the chemiluminescent technology and the biotin-avidin immune amplifying technological principle are effectively utilized, horse radish peroxidase is adopted to be as the marker enzyme, the content of the thyroid peroxidase autoantibodies in human serum samples is quantitatively detected, and the detection sensitivity can be ensured. The kit of the invention has the advantages of high sensitivity, good repeatability, good stability and high detection efficiency, and can provide a timely and reliable experimental basis for the clinical diagnosis and the treatment of thyroid disorders.

The invention belongs to the field of pharmaceutical preparations, and provides a pharmaceutical albumin nanoparticle, a preparation method and application of the nanoparticle to tumor targeting therapy. The nanoparticle is made from two types of proteins, namely avidin and albumin, encapsulating slightly-soluble antitumor drugs. The electrostatic interaction exists between avidin and albumin, and avidin in the nanoparticle can be combined with biotin. Avidin can target the nanoparticle encapsulating the drugs on a biotin enrichment part. Before the application of the nanoparticle, a biotinylated antibody is used for pre-targeting on a tumor part, and can improve the distribution of a nanoparticle preparation in the tumor part. The biotinylated antibody and the nanoparticle preparation are combined for therapy, thereby playing better antitumor effect than the effect played by the combination of a monoclonal antibody and an albumin nanoparticle without avidin.

The invention particularly relates to a kit for determining the surface antigen of the hepatitis B virus, and a preparation method thereof, which belongs to the medical field of immunological analysis. The kit comprises (1) a hepatits B virus surface antigen calibration material; (2) an avidin-coated carrier; (3) the polyclonal antibody or monoclonal antibody of a biotinylated hepatitis B virus surface antibody; (4) the polyclonal antibody or monoclonal antibody enzyme-labeled of the surface antibody; and (5) a chemiluminescent primer. Furthermore, the preparation method comprises the following steps of (1) preparing a calibration material from the pure surface antigen; (2) coating the carrier with avidin; (3) performing biotinylation of the polyclonal antibody or monoclonal antibody of the surface antibody; labeling the polyclonal antibody or monoclonal antibody of the surface body with an enzyme; (4) sub-packaging the calibration material and the chemiluminescent primer; and (5) assembling. The kit has the advantages of simpliness, rapidness, sensitiveness, stability and the like.

The invention provides a kit for detecting a serum anti-Annexin A2-IgG antibody. The detection kit of the invention adopts a target antigen Annexin A2 corresponding to an anti-Annexin A2-IgG antibodyof a primary nephrotic syndrome-related biomarker, uses human anti-tag peptide IgG as a standard substance for quantitative detection, and utilizes a biotin-labeled detection antibody and an enzyme-labeled streptavidin amplification system, thereby improving the accuracy and sensitivity of serum anti-Annexin A2-IgG antibody detection, and providing a better detection method for the diagnosis and treatment of primary nephrotic syndrome with the anti-Annexin A2-IgG antibody.

The invention belongs to the field of clinical laboratory techniques and in particular relates to a colloidal gold test strip for quantitatively detecting human bone metabolic biomarker and a detection device applying same. The test strip provided by the invention comprises a sample pad, a glass fiber mat coated with gold-labeled streptavidin, a glass fiber mat coated with a gold-labeled antibody, a nitrocellulose membrane and an absorbent pad which are sequentially adhered with one another on a bottom plate in a staggered manner. A quality control line pre-enveloped with a goat anti-rat IgG antibody is formed in the nitrocellulose membrane; a detection line parallel to the quality control line is formed in the nitrocellulose membrane; an antibody capable of being specifically bound with a to-be-detected antigen human bone metabolic biomarker is coated on the detection line; the gold-labeled antibody is an antibody capable of being specifically bound with the to-be-detected antigen human bone metabolic biomarker. According to the test strip provided by the invention, the human bone metabolic biomarker can be quantitatively detected, the requirement on instruments is low, the time of clinically detecting the human bone metabolic biomarker is shortened, and the detection complexity and cost can be reduced.

The invention relates to a preparation method and application of an electrochemical sensor for achondroplasia prenatal diagnosis gene-fibroblast growth factor receptor 3 (FGFR3) gene polymorphism detection, belonging to the technical field of electrochemical detection. The preparation method is characterized by comprising the following steps: synthesizing a Hemin-MOFs composite material, reducing platinum nanoparticles onto the Hemin-MOFs composite material, and mixing a single-strand DNA signal probe with the composite material to obtain a biological signal probe; and carrying out layer-by-layer self-assembly by using reducible graphene oxide tetraethylenepentamine, nano gold and avidin to fix the biotinylated DNA capture probe, thereby preparing the electrochemical sensor for FGFR3-1138G>A gene polymorphism detection. The sensor is successfully used for detecting FGFR3-gene single base mutation. The sensor has the advantages of high sensitivity and high specificity, and is quick and convenient for detection. The invention provides a new detection method for prenatal noninvasive diagnosis of achondroplasia.

It is an object of the present invention to provide a mutant streptavidin wherein the immunogenicity (antigenicity) in mammals of a streptavidin is reduced. The present invention provides a mutant streptavidin, which comprises an amino acid sequence in which (a) the arginine residue at position 72 is substituted with another amino acid residue, and (b) any one or more of the tyrosine residue at position 10, the tyrosine residue at position 71, the glutamic acid residue at position 89, the arginine residue at position 91, and the glutamic acid residue at position 104 are substituted with other amino acid residues, with respect to the amino acid sequence of a core streptavidin as shown in SEQ ID NO: 2, and which has decreased immunogenicity as compared with that of a wild-type streptavidin.

The invention relates to a liquid-phase chip kit for acute coronary syndrome and a preparation method for the same. A liquid-phase chip mainly comprises microspheres coated with oxidized low density lipoprotein (ox-LDL), soluble CD40 ligand (sCD40L), matrix metallopeptidase 9 (MMP-9), tissue factor (TF), omentin and endogenous secretory receptor of advanced glycation end products (esRAGE) capture antibody respectively, detection antibodies labelled by biotin, and streptavidin phycoerythrin. The liquid-phase chip provided by the invention has the advantages of being high in detection efficiency, low in the quantity of the needed samples, strong in specificity, high in sensitivity, rapid and accurate in detection, and the like. Simultaneously, the chip reflects a protective factor level and an injury factor level in an organism, so that the risk stratification and prognosis conditions of a patient can be much comprehensively assessed. Simultaneously, the preparation method disclosed by the invention is simple and practicable, and good in stability, various process parameters such as the quantities of the microspheres and the antibodies, and the reaction process in the technical scheme of the preparation method are obtained on the basis of lots of experiments, and are the optimal parameter values of the preparation process.