201 results about "Nonspecific binding" patented technology

The invention belongs to the technical field of biological detection, and particularly relates to a monoclonal antibody combination for detecting measles virus nucleoprotein and application of the monoclonal antibody combination. The combination is composed of monoclonal antibodies 5E2 and 5G9 and can efficiently and specifically recognize measles virus nucleoprotein, amino acid sequences of complementary determining regions (CDR) of heavy chain and light chain variable regions of the combination are clear and are shown as SEQ ID NO.1-12 respectively, high specificity and high affinity of the antibodies are guaranteed, the antibody combination can effectively capture and detect target antigens, and the antibody combination can be used for detecting measles virus nucleoprotein. The risk of non-specific binding and cross reaction is obviously reduced. The combination shows excellent sensitivity and specificity in detection platforms such as colloidal gold immunochromatography, and provides a stable and reliable biological recognition tool for rapid and accurate detection of measles viruses.

The invention provides a kit and a method for detecting common fusion genes of lymphoid leukemia based on a multiple digital PCR (Polymerase Chain Reaction) method. By constructing a synergistic effect mechanism of the primer and the fluorescent probe and optimizing matching of the primer, the probe and a fluorescent marker, non-specific binding among amplification products is effectively avoided. A composite reaction aid with a specific formula, namely a PCR enhancer, is innovatively introduced, so that the amplification efficiency and specificity of a multiple detection system are remarkably improved. According to the kit provided by the invention, the integrated detection capability on seven fluorescent channels, namely Atto 425, VIC, FAM, ROX, CY5, CY5.5 and CY7, is realized in a single-hole design. By innovatively constructing an ROX + CY5 and Atto425 + VIC dual-channel joint detection system, when the ROX and CY5 channels or Atto425 and VIC channels in the same detection hole simultaneously present positive signals, two additional detection targets can be specifically interpreted. The innovative detection strategy based on channel combination enables the kit to realize precise detection of 18 fusion genes only through two detection holes in a breakthrough manner.

The invention relates to the technical field of fluorescent probes, and provides a low-concentration ratio type high-concentration enhanced fluorescent probe as well as a preparation method and application thereof in order to solve the problems that a traditional fluorescent probe depends on a high-concentration use condition and is often faced with fast probe consumption, increased biotoxicity, non-specific target binding and the like in a biological sample. The preparation method of the fluorescent probe comprises the following steps: step 1, preparing phenothiazine dialdehyde; and 2, mixing phenothiazine dialdehyde, malononitrile, ethanol, acetonitrile, DMF and piperidine, and carrying out a reflux reaction to obtain the low-concentration ratio-type high-concentration enhanced fluorescent probe. The probe provided by the invention realizes quantitative detection of HClO through synchronous change of two emission channels, and the detection sensitivity and reliability are remarkably improved; when the concentration is high, an enhanced single-channel fluorescence amplification effect is shown, and strong signal identification and macroscopic visual imaging in specific application are facilitated, so that the dual requirements of trace monitoring and high-throughput screening are met.

The invention belongs to the technical field of drug sustained release, and particularly relates to a preparation method and application of a BMP-2 controllable sustained-release flocculent body based on lysozyme self-regulation. The preparation method comprises the following steps: preparing a chitosan solution; sequentially adding a protein stabilizer and glycerol into the chitosan solution obtained in the step A1 to prepare a chitosan composite solution; obtaining a non-specific binding solution; preparing BMP-2 / chitosan solid particles by adopting a freeze drying method; the preparation method comprises the following steps: preparing a PLGA / PEG composite solution to obtain a suspension, and carrying out post-treatment on the suspension to form the BMP-2 controllable slow-release flocculent. The carrier in the BMP-2 controllable slow-release flocculent body prepared by the preparation method can be specifically degraded by lysozyme in a human body, so that the release amount and the release speed of BMP-2 can be automatically adjusted according to a bone healing process, and long-time continuous release of the BMP-2 controllable slow-release flocculent body is realized. The problems that in the prior art, the slow release effect of a hydrophilic material on BMP-2 is poor, sudden release of factors is easily formed, and the slow release time and the slow release dosage are not controllable are solved.

The invention discloses a preparation method of a triple detection kit for influenza A, influenza B and new coronavirus antigens, and belongs to the field of respiratory virus in-vitro detection. In the antibody labeling stage, the antigen and the antibody can be more sufficiently combined in a manner of adding the linking arm, so that the antigen detection sensitivity can be improved. In the metal spraying stage, a novel coronavirus monoclonal antibody, an influenza A virus monoclonal antibody and an influenza B virus monoclonal antibody marked by latex microspheres are sequentially subjected to multi-layer metal spraying at the same position by a metal spraying instrument, the two antibodies are isolated by a trehalose solution, and metal spraying of three layers of antibodies isolated from each other is completed. And the cross reaction between different antibodies of the conjugate pad in the storage process is avoided, so that non-specific binding is avoided, and the storage stability is improved. The detection kit prepared by the method can specifically detect the novel coronavirus, the influenza A virus and the influenza B virus, and has the advantages of high sensitivity, good repeatability and the like.

The invention discloses an anti-soluble transferrin receptor monoclonal antibody as well as a preparation method and application thereof, and belongs to the technical field of antibody detection. According to the antibody, an L101-F760 amino acid sequence of human TfR protein is used as an immunogen, specific screening of B cells, reverse RNA (Ribonucleic Acid) into cDNA (Complementary Deoxyribose Nucleic Acid) through RT-PCR (Reverse Transcription-Polymerase Chain Reaction), then homologous recombination is performed to construct heavy and light chain vectors, and finally multiple rounds of screening are performed to obtain the purified sTfR monoclonal antibody, so that the sTfR protein can be specifically recognized, and the antibody has the advantages of high specificity and high sensitivity and can be widely applied to the field of immunotherapy. The natural sTfR protein in human serum can be recognized. The kit is applied to the detection and screening fields of immunohistochemistry, immunofluorescence chemistry, western blot, co-immunoprecipitation, indirect ELISA, flow cytometry and the like, especially has low background and no interference of non-specific binding impure protein during immunohistochemistry detection, can obtain more accurate detection and evaluation results, avoids interference of false positive and false negative, and has high detection accuracy. The method has great application value in the aspects of basic scientific research and clinical pathology detection.

A modified dsRNA, a double-stranded RNAi agent, and a use thereof. The modified dsRNA and the double-stranded RNAi agent can reduce non-specific binding, thereby reducing off-target toxicity, and improving the inhibitory activity on each target.

The invention belongs to the field of molecular sieve material characterization, and particularly relates to a method for analyzing aluminum atom pairs in a ZSM-5 molecular sieve based on super-resolution fluorescence microscopic imaging, which comprises the following steps: activating a ZSM-5 molecular sieve sample; contacting the obtained sample with probe molecules; washing the ZSM-5 molecular sieve sample, and removing unbound or nonspecifically bound probe molecules; imaging the marked sample by using a super-resolution fluorescence microscope to obtain an image sequence containing a single fluorescent molecule emission event; processing the image sequence, determining a space coordinate of each fluorescence event, and reconstructing a super-resolution fluorescence image exceeding an optical diffraction limit; and based on the space coordinates of the fluorescent dots in the super-resolution fluorescence image, carrying out statistics to obtain the position, surface density or distribution information of the aluminum atom pairs in the ZSM-5 molecular sieve. According to the method disclosed by the invention, nanoscale spatial resolution, direct imaging and quantitative analysis of Al-pair in ZSM-5 (Zeolite Socony Mobil-5) can be realized.

The invention belongs to the technical field of immunochemiluminescence, and relates to a PAMAM-mediated labeled small molecule compound and a synthesis method and application thereof.The PAMAM-mediated labeled small molecule compound is composed of small molecules, PAMAM and a marker, and the small molecules are provided with active groups or provided with derivative groups capable of reacting with amino under certain activation conditions to form covalent binding; the marker is provided with a succinimide group. The difference between a coupling product and a small molecular structure is reduced to the maximum extent through PAMAM mediation, the PAMAM dosage is extremely small and stable, compared with PEG, the molecular weight is more uniform, non-specific binding caused by hydrophobic interaction can be greatly reduced in immunoreaction, and good signals and separation can be obtained without purification of the product.

Provided is a method of testing an analyte in a sample. The method comprises: causing a first proximity probe and a second proximity probe to bind to an analyte in a sample in sequence to form an immune complex, the immune complex being captured on a solid-state matrix by means of binding of the first proximity probe to a capture probe, and adding a blocker after the first proximity probe binds to the capture probe and before the second proximity probe is added, the blocker binding to the capture probe to reduce non-specific binding of the capture probe to molecules other than the immune complex. Also provided is a blocker for the method.

The invention belongs to the technical field of biomedicine, and discloses an antinuclear antibody IgG indirect immunofluorescence detection method and system, and the detection standardization degree and the result reproducibility are significantly improved through the full-automatic system design in combination with precise mechanical transmission and an automatic sample adding device. Through an optimized FITC labeling system and a refined washing procedure, non-specific binding is remarkably reduced, and meanwhile, the binding efficiency of the antinuclear antibody and the secondary antibody is improved, so that the detection sensitivity is improved. Through the design of the automatic sample adding and sheet sealing device, the sample treatment efficiency is greatly improved, and simultaneous detection of large-scale samples can be realized. Through combination of a high-resolution imaging system and an intelligent image analysis algorithm, morphological characteristics and distribution rules of fluorescence signals are automatically extracted, and the accuracy and objectivity of a detection result are greatly improved.

The invention belongs to the technical field of protein calibration, and particularly relates to an enhanced protein-free confining liquid for protein detection, which comprises the following components: trihydroxymethyl aminomethane, sodium chloride, Tween-20, polyvinyl alcohol, trehalose, EDTA (Ethylene Diamine Tetraacetic Acid) and a polyoxyethylene-polyoxypropylene block copolymer, and sodium chloride and trehalose are matched to provide ions and small molecular compounds to form a stable closed environment. Wherein the trehalose assists in filling and covering small pores of PVDF, the sodium chloride provides ion balance, the EDTA-Na is used for precipitating metal ions, and the Tween-20 assists in repairing the PVDF film. According to the invention, the polyvinyl alcohol and the polyoxyethylene-polyoxypropylene block copolymer are mixed for use, so that non-specific sites on the membrane are blocked while impurity proteins are prevented from being introduced, the sealing effect is achieved, and the problem of false positive or non-specific binding easily caused by the traditional sealing liquid is effectively solved.

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 invention belongs to the technical field of biological detection, and particularly relates to a monoclonal antibody combination for detecting porcine epidemic diarrhea virus NP protein and application of the monoclonal antibody combination. The combination is composed of monoclonal antibodies 1E11 and 5C8 and can efficiently and specifically recognize porcine epidemic diarrhea virus NP protein, amino acid sequences of complementary determining regions of heavy chain and light chain variable regions of the combination are clear and are shown as SEQ ID NO.1-12 respectively, high specificity and high affinity of the antibodies are guaranteed, the antibody combination can effectively capture and detect target antigens, and the antibody combination can be used for detecting the porcine epidemic diarrhea virus NP protein. The risk of non-specific binding and cross reaction is reduced. The combination shows excellent sensitivity and specificity in detection platforms such as colloidal gold immunochromatography and the like, and provides a stable and reliable biological recognition tool for rapid and accurate detection of the porcine epidemic diarrhea virus.

The invention belongs to the technical field of biochemical detection, and particularly relates to a micro-fluidic chip PSMA prostate cancer circulating tumor cell immunoenrichment detection kit and a preparation method thereof. According to the kit, an EpCAM antibody, a Vimentin antibody and a double-site PSMA capture combination are fixed in a chip channel through a streptavidin-biotin system, double enrichment of epithelial and mesenchymal CTCs is achieved, PSMA targets are recognized through combination of an aptamer and the antibody, and the detection specificity and sensitivity are improved. Competitive oligopeptides are further introduced to block non-specific binding sites on the surfaces of leukocytes and reduce false positive. By combining a multiple fluorescent chromosome system and a double-antibody nucleic acid probe signal amplification strategy, accurate recognition and quantification of CTC and PSMA positive cells are realized. The scheme is suitable for early screening, curative effect evaluation and relapse monitoring of prostate cancer, and has a good clinical application prospect.

The invention discloses a zwitter-ion modified nucleic acid aptamer and a preparation method thereof, and belongs to the field of biological medicine. Wherein both the zwitterion and the aptamer have functional activity, the zwitterion has an anti-nonspecific binding effect, the aptamer can actively target a target molecule, and the zwitterion and the aptamer are coupled together through a click chemistry reaction. The zwitter-ion modified aptamer provided by the invention not only is flexible in construction mode, but also can resist the adsorption effect of proteins and cells on the aptamer, and improves the specific targeting ability of the aptamer to target molecules in a complex environment.

The invention provides a tsutsugamushi disease pathogen detection primer, a probe and a kit, the sequences of the primer and the probe in an asymmetric primer ERA detection system are designed and screened according to the target sequence of a tsutsugamushi disease pathogen gene, and the proportion of upstream and downstream primers and an amplification reaction system are optimized; the nucleic acid sequence of the tsutsugamushi disease pathogen can be specifically recognized, and non-specific binding with other irrelevant nucleic acid is reduced, so that the detection specificity is improved; meanwhile, efficient amplification of the tsutsugamushi disease pathogen nucleic acid is achieved, accurate detection can be achieved even under the condition that the virus nucleic acid content is extremely low, and therefore the detection sensitivity and the amplification efficiency are improved.

The invention belongs to the technical field of immunohistochemical detection, and discloses a modified composite sealing buffer solution as well as a preparation method and detection application thereof. The modified composite blocking buffer solution comprises a basic buffer system, a composite blocking agent, a nonionic detergent, an endogenous interferent blocking agent and an antibody stabilizer, wherein the basic buffer system provides a stable pH environment and ionic strength; the composite sealing agent firstly occupies a shielding site, and the background is lowered; the nonionic detergent destroys hydrophobic interaction, effectively elute and loosen adsorbed molecules, and promote dissolution of components with relatively strong hydrophobicity; the endogenous interferent blocker can be combined with a receptor firstly, so that non-specific combination of an antibody and the receptor is blocked, and the problem of specific background is solved; the antibody stabilizer can protect the activity of the detection reagent and maintain the stability, and the obtained modified composite sealing buffer solution and the kit thereof have the advantages of multiple cooperative sealing mechanisms, prospective blocking of endogenous interference, improvement of the stability, compatibility and high efficiency of the antibody and the like.

The present invention relates to a polymer conjugate comprising a ULA polymer a) and one or more polypeptides b), wherein the polypeptides are conjugated to the ULA polymer, and the conjugate is coated on the surface of a device for culturing cells. The peptides can interact with receptors on the surface of the cells, while the polymer prevents non-specific binding of the cells to the surface of the device.

The invention discloses a B cell epitope on the surface of glyceraldehyde-3-phosphate dehydrogenase protein, a nucleic acid molecule of the B cell epitope and application of the B cell epitope to detection of mycoplasma hyopneumoniae infection. The B cell epitope can be expressed on the surface of an inert carrier S9 thallus in a functional exhibition mode, an LN7-antibody direct-mediated agglutination test detection method established based on the LN7 expressed on the surface of the S9 thallus in the functional exhibition mode is adopted, the LN7 only specifically recognizes a mycoplasma hyopneumoniae infected serum antibody and a vaccine immune serum antibody containing a GAPDH antigen, a specific binding reaction is conducted, and the mycoplasma hyopneumoniae infected serum antibody and the vaccine immune serum antibody containing the GAPDH antigen can be detected. And cross reaction and non-specific binding reaction with other mycoplasma pathogens, porcine respiratory disease pathogen infection serum and vaccine immune serum are avoided. The diagnosis method is expected to become an important technical means for accurate diagnosis of mycoplasma hyopneumoniae infection and monitoring and evaluation of the immune effect of the mycoplasma hyopneumoniae vaccine.

An IgG1 Fc monomer, a preparation method therefor and an application thereof. Causing an Fc dimer of a novel IgG1 Fc monomer sequence for which an antibody IgG1 constant region is modified to become an Fc monomer by means of the modification on a human antibody IgG1 constant region Fc that uses antibody engineering technology, and maintaining an FcRn binding function; the present application has the feature of very low non-specific binding with unrelated proteins, and the main features of the Fc monomer comprise the T366, L368, P395, and K409 positions in a CH3 region of the constant region of the antibody having mutations, and the monomer being highly efficiently expressed in prokaryotic cells; the monomer may bind to FcRn by using a pH-dependent specific binding mode, and has the feature of very low non-specific binding. By using said Fc monomer, the same may be fused or coupled with various proteins, polypeptides, small molecules, nucleic acids and the like for different targets such that the fused or coupled molecules have the feature of being capable of binding to FcRn by using pH dependence.

The invention provides a super-sensitive molecule system for biological signal amplification, a detection method and application, and belongs to the technical field of biological sensing. The super-sensitive molecular system for biological signal amplification is composed of a hairpin probe H and gold nanoparticles (TS (at) CP (at) loading a trajectory chain TS and a capture chain CP (CP), a traditional DNA walking machine walking chain is split into the hairpin probe H and the capture chain CP which are spatially isolated, and a target-dependent activation mechanism is constructed: when no target exists, the hairpin probe H realizes self-protection through a self-folding stem-loop structure; non-specific binding with the capture chain CP / trajectory chain TS is blocked; after the target is beaten on the clamping probe H, the exposed sequence of the clamping probe H is hybridized with the capture chain CP to form a complete walking chain, and a signal amplification reaction driven by cutting incision enzyme is triggered, so that the problem of false positive caused by co-localization of the walking chain and a track chain interface is fundamentally solved.

The invention relates to the technical field of biological medicine detection, and particularly discloses an electrochemical luminescence kit for rapidly detecting tumor markers, which comprises a capture molecule, an electrochemical luminescence ECL labeled molecule, a biotin labeled detection antibody, a streptavidin fixed plate and a liquid reagent, according to the present invention, the capture molecule, the ECL labeling molecule, the biotin labeling detection antibody and the streptavidin fixation platform interact to form the novel multi-protein complex, such that each target antigen can initiate multiple signal conversion during the reaction process; theoretically, the tetramolecular structure can obviously improve the signal transmission efficiency, so that the low-abundance tumor marker can be quickly and accurately detected, and the high-specificity recognition of the target tumor marker is realized by capturing molecules and detecting antibodies. The high affinity between biotin and streptavidin is utilized, so that non-specific binding is greatly reduced, background signals are reduced, and the accuracy and reliability of detection are improved.

The present invention relates to a fusion protein platform with improved half-life, which uses an IgG Fc region, an IgM region, a J chain, and / or a linker. The present invention also relates to a fusion protein produced through the platform, and in particular, to a fusion protein comprising an IgG Fc region, an IgM region, a J chain, a linker, and / or a biologically active molecule. The fusion protein platform according to the present invention can be used in combination with various biologically active molecules selected according to the purpose. In addition, the biologically active molecules included in the platform can have increased binding activity. Therefore, the fusion protein produced through the platform has excellent effect of recognizing and regulating the target, and there is little concern of unpredictable side effects due to non-specific binding. In addition, the half-life in the blood of the body is increased, so that the therapeutic effect to be achieved through the fusion protein can be maximized.

The invention discloses a detection method of inflammatory marker protein. According to the method, the micro-fluidic chip with a sample loading area, a buffer treatment area, a sample channel and a detection area is prepared on filter paper through wax printing; chitosan is preset in the sample loading area and is used for treating a sample, and bromothymol blue is fixed in the detection area and is used as a pH indicator. During detection, a sample is driven by a phosphate buffer solution with the pH value of 6.0 to flow to a detection area through capillary action, the C-reactive protein and the indicator are subjected to non-specific binding, so that the color of the detection area is changed from yellow to green, the length of a green developing signal is in direct proportion to the concentration of the CRP, and quantitative detection can be realized by measuring the length. The method does not need an antibody, is low in cost, is simple and convenient to operate, can complete detection within 15 minutes, has the detection limit of 1.56 ng / ml and the linear range of 5-25 ng / ml, and is suitable for rapid screening and field detection of basic medical institutions.

The invention belongs to the technical field of electrochemical analysis and detection, and particularly relates to an electrochemical immunosensor for detecting adiponectin as well as a preparation method and application of the electrochemical immunosensor. The preparation method comprises the following steps: (1) connecting a screen-printed electrode SPCE to an electrochemical workstation by using a 0.01 M PBS (Phosphate Buffer Solution) with the pH value of 7.4, performing-0.2 V-1. 2V cyclic voltammetry scanning, and activating for 10 circles under 50mV / S; and (2) by taking 0.01-1M H2SO4 as a base solution, connecting the screen-printed electrode SPCE to an electrochemical workstation, carrying out electro-polymerization on poly-o-phenylenediamine in a 50-100mM o-phenylenediamine and NH2-UiO-66 solution to form a poly-o-phenylenediamine and NH2-UiO-66 composite modified electrode, washing with deionized water, and drying at room temperature. (3) soaking the modified electrode in a glutaraldehyde solution for 10-70 minutes, cleaning with deionized water, drying at room temperature, adding 10-100 [mu] L of ADPN antibody solution and 100-600 [mu] g / mL of ADPN antibody solution, and incubating; and (4) washing with ionized water, drying at room temperature, preventing non-specific binding sites at 37 DEG C for 0.5-1.5 hours by using 3-10 microliters of 0.8-1.2 wt% casein solution, and washing the screen-printed electrode again to obtain the electrochemical immunosensor.

Provided herein are compositions and methods for purifying and concentrating nucleic acids from large-volume samples. In particular, reagents are provided for non-specifically binding total nucleic acid to a solid surface, separating bound nucleic acid from a large-volume sample, separating nucleic acid from amplification inhibitors, and / or eluting nucleic acids into a small volume amenable to further analysis.

The invention relates to the technical field of molecular biology, and discloses an LAMP (loop-mediated isothermal amplification) primer group and a kit for detecting three items (Uu, CT and NG) of venereal diseases. The LAMP primer group disclosed by the invention comprises a first primer group for targeting a ureaplasma urealyticum UreB gene, a second primer group for targeting a chlamydia trachomatis gyrA gene and a third primer group for targeting a gonococcus glnA gene. The LAMP primer group provided by the invention has good thermal stability, is suitable for an LAMP amplification detection system at a high temperature of 70 DEG C, reduces non-specific binding, and has good detection sensitivity and specificity. The LAMP primer group and the kit provided by the invention provide an innovative solution for accurate diagnosis of sexually transmitted diseases.

The invention relates to the technical field of biological detection, and discloses a sample diluent and application thereof and a kit, pure water is taken as a solvent, and the sample diluent at least comprises 15-80 g / L of soluble sodium salt, 0.05-0.5 g / L of soluble potassium salt, 8-15 g / L of amino acid, 0.2-1 g / L of goat serum albumin, 0.2-1 g / L of surfactant, 0.5-2 g / L of trehalose and 0.5-2 mL / L of Proclin-300 according to concentration, the sample diluent provided by the invention can weaken non-specific binding of impurities in a blood sample and a target analyte, so that the accuracy of a final detection result is improved.

A high-throughput screening system and method for small molecule-protein interactions includes first immobilizing selected small molecules on a solid matrix. Immobilization is preferably performed via photoaffinity labeling, where a linker is used to bind the small molecule to the matrix. cDNA libraries are constructed based on various human tissues. Tissue mRNA is transcribed into cDNA and transferred to a phage genome to construct a phage display library, which is then mixed with small molecules conjugated to microspheres and incubated. The incubated mixture is washed to remove unbound phages, including non-specific and weakly bound phages. Bound phages are amplified and used for the next round of biopanning. The biopanning cycle is repeated, and then PCR is performed on each plaque obtained from the final round of biopanning. The PCR products from each small molecule experiment are barcoded, merged, and then subjected to next-generation sequencing.