65 results about "Avidin" patented technology

The invention belongs to the technical field of biological detection, and particularly relates to a monoclonal antibody 4F6 for HPV16 type E7 protein detection and application. The heavy chain variable region CDR sequences and the light chain variable region CDR sequences of the antibody are SEQ ID NO.1-3 and SEQ ID NO.4-6 respectively, and the antibody can be specifically combined with HPV16 type E7 protein without cross reaction. A double-antibody sandwich ELISA detection system constructed based on the antibody is combined with a biotin-avidin amplification technology, the sensitivity reaches 100 pg / mL, and the antibody is suitable for rapid detection of the HPV16 type E7 protein in a cervical exfoliated cell sample. The invention further provides the HPV16 type E7 recombinant protein which is obtained through prokaryotic expression and has immunocompetence, and the HPV16 type E7 recombinant protein is applied to antibody screening and detection. Compared with nucleic acid detection, the method has a lower false positive rate, can be used for early screening of cervical cancer and precancerous lesions, and has a good application prospect.

The present invention belongs to the field of biological detection technology, specifically relating to a monoclonal antibody combination for detecting HPV18 E7 protein and its application. This combination consists of monoclonal antibodies 5F8 and 6G6, wherein the heavy and light chain variable regions of 5F8 and 6G6, respectively, contain specific complementarity-determining region sequences (as shown in SEQ ID NOs. 1 to 12), conferring high specificity for HPV18 E7 protein. Verification using a double-antibody sandwich ELISA and a biotin-avidin amplification system demonstrated that this antibody combination specifically recognizes HPV18 E7 protein, exhibits no cross-reactivity with other high-risk HPV oncoproteins, and exhibits a detection sensitivity of 1 ng / mL. This combination can be used to construct detection systems such as ELISA kits and immunochromatographic test strips, suitable for rapid screening of HPV18 E7 protein in cervical exfoliated cell samples.

The invention relates to the technical field of biological detection, in particular to a monoclonal antibody combination for HPV18 type E6 protein detection and application. The provided combination is composed of 5G3 and 2C7, and the amino acid sequences of complementary determining regions of variable regions of a heavy chain and a light chain of the combination are clear and are respectively shown as SEQ ID NO.1-12. The antibody combination has high specificity and sensitivity, the lowest detection limit can reach 100 pg / ml, and cross reaction with other HPV subtypes is avoided. According to a double-antibody sandwich ELISA and biotin-avidin amplification detection system constructed based on the combination, the signal intensity and the detection accuracy are remarkably improved, and the combination is suitable for rapid detection of the HPV18 type E6 protein in a cervical exfoliated cell sample and has application value in early diagnosis of cervical cancer, risk stratification, vaccine research and development and curative effect evaluation.

The invention belongs to the technical field of gene engineering, and particularly relates to a biotin ligase mutant as well as a coding gene, an expression vector, a recombinant cell and application thereof. The amino acid sequence of the biotin ligase mutant is as shown in SEQ ID NO. 2. The biotin ligase (Bar A) mutant provided by the invention can be efficiently expressed in eukaryotes, the expression level of the biotin ligase (Bar A) mutant is obviously improved in mammalian cells compared with a wild type, and the biotin ligase (Bar A) mutant has good catalytic activity after expression, can effectively catalyze biotinylation of protein containing a biotin receptor sequence, and has good application prospects. The method has a wide application prospect in the fields of biotinylated protein preparation, and protein labeling, positioning, immunodetection, affinity purification, function research and the like based on a biotin-avidin system (BAS).

The present invention relates to the field of biological detection technology, and in particular to a monoclonal antibody combination and application for the detection of HPV18 type E6 protein. The provided combination consists of 5G3 and 2C7, and the amino acid sequences of the complementary determining regions of the heavy chain and light chain variable regions are clear, as shown in SEQ ID NO.1-12, respectively. The antibody combination has high specificity and sensitivity, with a minimum detection limit of up to 100 pg / ml, and does not cross-react with other HPV subtypes. The double-antibody sandwich ELISA and biotin-avidin amplification detection system constructed based on the combination significantly improves the signal intensity and detection accuracy, is suitable for the rapid detection of HPV18 type E6 protein in cervical exfoliated cell samples, and has application value in the early diagnosis of cervical cancer, risk stratification, vaccine development and efficacy evaluation.

The invention discloses a diabetic bone defect repair hydrogel stent capable of slowly releasing exosome and a preparation method of the diabetic bone defect repair hydrogel stent. The preparation method comprises the following steps: preparing biotinylated quaternized chitosan methacrylate (QCS-MA-Biotin), formylated oxidized dextran and a biotinylated exosome (Exo-Bio), carrying out avidin bridging, and carrying out photocuring, so as to form the double-network hydrogel. The scaffold disclosed by the invention has a pH-responsive slow-release characteristic, the 28-day release rate of the exosome is less than or equal to 50%, and the activity retention rate gt; in addition, the repair of the diabetic bone defect can be obviously promoted. The method is suitable for repairing defects of skull, alveolar bone and the like.

The invention provides a streptococcus suis polysaccharide protein conjugate vaccine as well as a preparation method and application thereof, and belongs to the technical field of vaccine preparation. The vaccine comprises a polysaccharide-protein conjugate formed by coupling streptococcus suis type 2 capsular polysaccharide and streptococcus suis type 2 recombinant protein. The preparation method comprises the following steps: S1, preparing streptococcus suis type 2 capsular polysaccharide; s2, preparing streptococcus suis type 2 recombinant protein; s3, activating polysaccharide; s4, combining the biotinylated polysaccharide with the recombinant protein containing the avidin structural domain to form a stable polysaccharide-protein conjugate; s5, removing unbound proteins; and S6, mixing the polysaccharide-protein conjugate with the oil-water emulsion in proportion. By optimizing a coupling technology and a vaccine preparation formula, the immunogenicity and the protection effect of the vaccine are improved, the safety and the broad-spectrum cross protection capability of the vaccine are remarkably enhanced, the complexity and the cost of a vaccine production process are reduced, and the vaccine has a good industrial application prospect and a good popularization value.

The present invention relates to a monoclonal antibody capable of binding to biotin. In one embodiment the monoclonal antibody according to the invention also does not bind to a biotin moiety on a biotinylated molecule, wherein the biotin moiety is attached to the molecule via the carbon atom of the carboxyl function of the valeric acid moiety of biotin. Also disclosed is a method for generation of an antibody as disclosed herein. The monoclonal antibody according to the invention is of specific use in a method for measuring an analyte in a sample, wherein a (strept)avidin / biotin pair is used to bind a biotinylated analyte specific binding agent to a (strept)avidin coated solid phase.

The invention belongs to the technical field of biological detection, and particularly relates to a monoclonal antibody 1E12 for specific detection of AAV6 and application of the monoclonal antibody 1E12. According to the monoclonal antibody 1E12 provided by the invention, a heavy chain variable region and a light chain variable region respectively comprise three complementary determining regions (CDR) corresponding to SEQ ID NO.1-3 and SEQ ID NO.4-6. The CDRs endow the antibody with high specificity and affinity to AAV6, the antibody can accurately recognize AAV6 virus without cross reaction with other serotypes, and the detection sensitivity reaches 4 * 10 < 6 > vg / ml level. The antibody is suitable for development of multiple detection tools such as a double-antibody sandwich ELISA kit, a test strip and an antibody chip, especially has excellent performance in a biotin-avidin amplification system, can be used for virus identification, titer determination and clinical dose evaluation of AAV6, and provides an effective means for standardized and high-throughput detection.

The invention relates to a porcine bacterial polysaccharide-viral protein conjugate vaccine as well as a preparation method and application thereof, and belongs to the technical field of animal vaccines. The vaccine takes porcine bacterial polysaccharide and virus protein as raw materials, and a polysaccharide-virus protein conjugate is formed through coupling of a biotin-avidin system; wherein the virus protein is selected from one of classical swine fever virus E2 protein, porcine circovirus type 2 Cap protein, porcine pseudorabies virus gD protein and the like, and the porcine bacterial polysaccharide is selected from one of streptococcus suis capsular polysaccharide, porcine pasteurella multocida capsular polysaccharide and the like. The vaccine can simultaneously induce an organism to generate a high-level IgG antibody aiming at porcine bacterium capsular polysaccharide and virus protein, so that synergistic immune protection on porcine bacterium and virus infection is realized, and a broad-spectrum cross immune effect is achieved.

The preparation method comprises the following steps: modifying and connecting IL-15 and PD-1 protein molecules by using biotin, modifying PLGA-PEG by using avidin, and finally preparing the double-targeting nano-micelle through specific binding of the biotin and the avidin and a self-assembly effect of the PLGA-PEG. The dual-targeting nano-micelle IL-15 / PD-1 / PEG-PLGA, which can efficiently target and activate NK cells and target surface high-expression PD-L1 tumor cells, is synthesized and prepared. The mole number of IL-15 and PD-1 loaded on the surface of the dual-targeting nano-micelle is close to 1: 1, and the dual-targeting nano-micelle is regular in form, uniform in dispersion and in the shape of a sphere with the particle size of 254.76 + / -28.02 nm. Meanwhile, it is verified that the dual-targeting nano-micelle IL-15 / PD-1 / PEG-PLGA can effectively improve the recognition and killing efficiency of the NK cells on tumor cells in vivo and in vitro.

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 invention belongs to the field of biology, and particularly relates to a chemiluminescence kit for detecting CEACAM1, a use method and application, the chemiluminescence kit comprises a streptavidin magnetic particle working solution, a biotinylated carcino-embryonic antigen related cell adhesion molecule 1 capture antibody solution and an acridinium ester labeled carcino-embryonic antigen related cell adhesion molecule 1 detection antibody solution. Coupling of acridinium ester and the antibody is efficient and simple, repeatability is good, large-scale production and application are easy, a biotin-avidin amplification system (BAS system) is used in a reaction system, quantitative detection of ultramicro markers is more sensitive and more efficient, and compared with a traditional enzyme-linked immunosorbent assay method, the method has the advantages that the detection sensitivity is high, and the sensitivity is high. The magnetic particle chemiluminescence reagent disclosed by the invention has the advantages of low cost, stable and reliable result, high test flux, convenience in production, small batch difference, easiness in large-scale application and the like.

The invention belongs to the technical field of biological detection, and particularly relates to a monoclonal antibody combination for NfL protein detection and application. The combination comprises monoclonal antibodies 9E1 and 10B4, and amino acid sequences of complementary determining regions of heavy chain and light chain variable regions of the monoclonal antibodies 9E1 and 10B4 are respectively shown as SEQ ID NO.1-12. The antibody combination can be used for constructing a double-antibody sandwich ELISA detection system and is especially suitable for being combined with a biotin-avidin signal amplification system to achieve high-sensitivity and high-specificity detection of the NfL protein, the detection sensitivity can reach 20 pg / mL, and the method is low in cost, easy and convenient to operate and suitable for quantitative analysis of the NfL protein in samples such as serum and plasma.

The invention relates to an alanine transaminase (ALT) detection reagent and a preparation method thereof, and belongs to the field of medical detection. The glutamic-pyruvic transaminase detection reagent is a nano antibody AC1 and AT1 which are combined with different binding sites of ALT, the nano antibody AC1 is immobilized on an avidin ELISA plate through biotinylation to serve as a capture antibody, and the nano antibody AT1 serves as a detection antibody. The glutamic-pyruvic transaminase detection reagent prepared based on the nano antibody and the detection method can meet the rapid and accurate glutamic-pyruvic transaminase detection requirements.

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 RNA rapid detection, and particularly relates to a rapid amplification and lateral chromatographic detection method for virus RNA and application. The crude virus nucleic acid extract is subjected to a single-tube composite enzyme reaction system reverse transcription, restriction endonuclease digestion and one-way isothermal strand displacement amplification, and then a large amount of specific sequence single-stranded DNA with a marker is generated; in the lateral chromatographic process, the single-stranded DNA is captured by a nucleic acid probe fixed on a detection area of a virus RNA detection test paper, at the same time, avidin labeled on a colloidal gold particle is combined with biotin labeled on the fixed single-stranded DNA, and the colloidal gold particle is indirectly fixed to show a color indication result. The method provided by the application is simple to operate, does not need complicated nucleic acid extraction, does not need large equipment in the whole detection process, and the result can be judged by naked eyes, so that on-site rapid detection can be realized, and the method has the advantages of simplicity, rapidness, high sensitivity and low cost.

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.

Presently disclosed is a linker useful for conjugating a protein or peptide that is labeled by an alkyne group to a biotin moiety, and methods for making and using the linker. One use of the linker is to identify or purify alkyne-tagged peptides. In such methods, the linker is joined to the alkyne group by a click reaction, and then the biotin-conjugated peptides are immobilized on an avidin- or streptavidin-coated substrate. Unbound peptides or proteins are washed away and then the immobilized peptides or proteins are cleaved from the substrate, preferably by a mild acid treatment. The thus isolated peptides can be analyzed by a variety of methods, e.g., to prepare a profile of labeled sites in a living cell.

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.

Labeled nucleotide analogs comprising at least one avidin protein, at least one dye-labeled compound, and at least one nucleotide compound are provided. The analogs are useful in various fluorescence-based analytical methods, including the analysis of highly multiplexed optical reactions in large numbers at high densities, such as single molecule real time nucleic acid sequencing reactions. The analogs are detectable with high sensitivity at desirable wavelengths. They contain structural components that modulate the interactions of the analogs with DNA polymerase, thus decreasing photodamage and improving the kinetic and other properties of the analogs in sequencing reactions. Also provided are nucleotide and dye-labeled compounds of the subject analogs, as well as intermediates useful in the preparation of the compounds and analogs. Compositions comprising the compounds, methods of synthesis of the intermediates, compounds, and analogs, and mutant DNA polymerases are also provided.

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 present invention relates to a monoclonal antibody capable of binding to biotin. In one embodiment the monoclonal antibody according to the invention also does not bind to a biotin moiety on a biotinylated molecule, wherein the biotin moiety is attached to the molecule via the carbon atom of the carboxyl function of the valeric acid moiety of biotin. Also disclosed is a method for generation of an antibody as discloed herein. The monoclonal antibody according to the invention is of specific use in a method for measuring an analyte in a sample, wherein a (strept)avidin / biotin pair is used to bind a biotinylated analyte specific binding agent to a (strept)avidin coated solid phase.

The invention belongs to the technical field of biological detection, and particularly relates to a monoclonal antibody combination for HPV18 type E7 protein detection and application. The combination consists of monoclonal antibodies 5F8 and 6G6, heavy chain variable regions and light chain variable regions of the 5F8 and 6G6 respectively comprise specific complementary determining region sequences (as shown in SEQ ID NO.1 to SEQ ID NO.12), and the combination is endowed with high specificity to HPV18 type E7 protein. Through verification of a double-antibody sandwich ELISA and a biotin-avidin amplification system, the antibody combination can specifically recognize the HPV18 type E7 protein and has no cross reaction with other high-risk HPV oncoproteins, and the detection sensitivity reaches 1 ng / mL. The combination can be used for constructing an ELISA kit, an immunochromatography test strip and other detection systems, and is suitable for rapid screening of the HPV18 type E7 protein in a cervical exfoliated cell 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.