138 results about "Biotin binding" patented technology

Methods of reversal of the binding between a biotin compound and a biotin-binding compound are disclosed. A method of reversibly releasing a biotinylated moiety from a streptavidin (or avidin) coated support is shown as an example. The strong interaction between streptavidin or avidin-biotin is made much weaker by using a combination of modified streptavidin or avidin and modified biotin like desthiobiotin or a derivative thereof like DSB-X Biotin. A protein, such as an antibody may be biotinylated with the modified biotin. When this protein is isolated by binding the modified biotin to the modified streptavidin or avidin bound to an solid surface, it may be released under very gently and very rapid conditions by addition of free biotin. In contrast to proteins obtained by the prior art release methods the protein obtained using the previously available release methods, the proteins obtained using the methods disclosed herein will maintain their native conformation. Uses of the methods in various procedures including cell detachment procedures and techniques of detection, identification, determination, purification, separation and / or isolation of target proteins or nucleic acid molecules are also described.

Methods of preparing targeting ligand bound avidin-lipid vesicles for use in preparing a targeted, therapeutic liposome composition are disclosed. Each vesicle comprises an avidin molecule coupled to the polymer-conjugated biotin which retains multiple free site biotin-binding sites such that the vesicle may be used to further couple a biotinylated-targeting ligand.

Provided herein are novel irreversible sialidase inhibitors. These compounds can be conjugated with a detectable tagging moiety such as azide-annexed biotin via CuAAC for isolation and identification of sialidases. The provided compounds and the corresponding detectable conjugates are useful for detecting sialidase-containing pathogens and imaging in situ sialidase activities under physiological conditions.

The invention relates to a colloidal gold immunochromatography test strip used for testing an H1N1 influenza antigen and a method for testing the H1N1 influenza antigen. The test strip comprises a base plate, a sample pad, a conjugate pad, a pyroxylin film and an absorbent paper, wherein the sample pad, the conjugate pad, the pyroxylin film and the absorbent paper are lapped and adhered on the base plate sequentially; the conjugate pad is a combination of a gold-label-biotin conjugate pad and a streptavidin-gold-antibody conjugate pad; according to the method for testing the H1N1 influenza antigen, a sample to be tested is dropwise added on the test strip; if a red band is displayed at a testing line (1), the sample to be tested contains the H1N1 influenza antigen. According to the advantages, the test strip provided by the invention is cheap in price, fast, simple, convenient, and greatly suitable for on-site testing; moreover, the test strip can meet the requirement of higher testing sensitivity, and has an important clinical diagnostic significance.

The invention relates to a method for sorting target cells by using avidin / streptavidin magnetic composite particles. In the method, a biotin-labeled monoclonal antibody is added into an experimental system, magnetic particles are bonded with the biotin-labeled monoclonal antibody through avidin / streptavidin, the monoclonal antibody is specifically bonded with corresponding antigen on the surfaceof the cells to make the cells captured by the magnetic particles so as to purify and separate the cells. Because the biotin-avidin and biotin-streptavidin have the characteristics of high system specificity, high stability, wide application range and low experiment cost, the obtained avidin / streptavidin magnetic composite particles have high biotin bonding property; and the labeled amount is improved in the measurement technique, and biomolecules are difficult to denature or inactivate, so that the cell sorting specificity is further improved. The high-purity target cells can be sorted by specifically bonding the biotin with the avidin or streptavidin; and the method has the advantages of no need of expensive instrument, simple operation and time saving.

The invention relates, in part, to monovalent streptavidin compositions. The invention also relates to methods of preparing and using monovalent streptavidin compositions. In some aspects of the invention, the compositions are monovalent streptavidin with a single femtomolar biotin-binding site.

Provided are streptavidin-bonded magnetic particles having a high biotin binding capability, and a manufacturing method for the same. Streptavidin-bonded magnetic particles are characterized by having a structure in which streptavidins are cross-linked on magnetic particles. A manufacturing method for streptavidin-bonded magnetic particles including the following steps. (1) A step for preparing a suspension containing magnetic particles having amino groups on the surface thereof; and (2) a step for adding glutaraldehyde to the suspension prepared in step (1), in the presence of streptavidin, and reacting the magnetic particles with the streptavidin and glutaraldehyde. These streptavidin-bonded magnetic particles, and streptavidin-bonded magnetic particles manufactured by means of this manufacturing method can be used in clinical diagnosis.

The invention relates to fusion proteins comprising a stress protein fused with an engineered antibody or fragment that binds to mesothelin, or a stress protein fused with a biotin-binding protein in combination with a biotinylated engineered antibody or fragment that binds to mesothelin. The invention also relates to fusion proteins comprising a stress protein fused with an antibody binding protein in combination with an engineered antibody or fragment that binds to mesothelin. The invention also relates to fusion proteins comprising an engineered antibody or fragment that binds specifically to mesothelin fused in frame with a biotin binding protein. The invention also provides fusion proteins comprising an engineered antibody or fragment, that binds to mesothelin, fused with an antibody binding protein. The invention also relates to methods of using fusion proteins of the invention to induce an immune response to mesothelin and to treat disease.

The present invention provides a method of binding a protein to a carrier in such a way that the protein is not impaired in its function but can be allowed to act more efficiently than when it is bound directly.The method of the present invention for binding a protein to a carrier comprises:preparing a biotin-bound carrier;preparing a fusion protein having the protein bound to a tamavidin; andbinding the protein to the carrier via tamavidin-biotin bonds.

Streptavidin-metallothionein chimeric proteins with biological recognition specificity in which the streptavidin moiety provides high affinity biotin binding and the metallothionein moiety provides a high affinity metal binding. The binding affinity of the streptavidin-metallothionein chimeric protein both for biotin and heavy metal ions allows specific incorporation into, conjugation with, or labelling of any biological material containing biotin with various heavy metal ions.

The present invention provides a streptavidin-coupled magnetic particle with high biotin-binding capacity, and a manufacturing method thereof. The streptavidin-coupled magnetic particle has a structure in which streptavidins are cross-linked with each other on a magnetic particle. A method for manufacturing the streptavidin-coupled magnetic particle includes the steps of:(1) preparing a suspension containing magnetic particles having amino groups on their surface; and(2) reacting the magnetic particles with streptavidin and glutaraldehyde by adding glutaraldehyde in the presence of streptavidin to the suspension prepared in step (1).The streptavidin-coupled magnetic particle of the present invention, and the streptavidin-coupled magnetic particle manufactured by the manufacturing method of the present invention are useful in clinical diagnosis.

The invention relates to an EV71 (Enterovirus) virus detection method based on magnetic microsphere separation and chemiluminescent immunity imaging. The method mainly comprises the following steps of: coupling an EV71 virus rabbit anti polyclonal antibody with a magnetic microsphere; adding a sample to be detected and the magnetic microsphere to a micropore plate to ensure that the virus in the sample to be detected is bonded with a virus polyclonal antibody; then adding a biotinlated EV71 virus VP1 protein rabbit anti polyclonal antibody to ensure that the EV71 virus VP1 protein rabbit anti-polyclonal antibody is in specific reaction with the sample to be detected; adding SA-HRP (Streptavidin-Horseradish Peroxide) to be bonded with biotin so as to form a magnetic microsphere-polyclonal antibody-virus-polyclonal antibody-HRP compound finally; and adding a chemiluminescent substrate, and detecting chemiluminescent intensity. In the invention, the chemiluminescent intensity is in direct proportion to the concentration of the virus to be detected, and a linear relation between the chemiluminescent intensity and the concentration of the EV71 virus to be detected can be obtained. The EV71 virus detection method has the advantages of simplicity and convenience for operation, high sensitivity, strong specificity and the like, and can better meet the demand of clinical detection of the EV71 virus.