232 results about "Antibody labeling" patented technology

Isolated, mammalian, adult bone marrow-derived, lineage negative hematopoietic stem cell populations (Lin− HSCs) contain endothelial progenitor cells (EPCs) capable of rescuing retinal blood vessels and neuronal networks in the eye. Preferably at least about 20% of the cells in the isolated Lin− HSCs express the cell surface antigen CD31. The isolated Lin− HSC populations are useful for treatment of ocular vascular diseases. In a preferred embodiment, the Lin− HSCs are isolated by extracting bone marrow from an adult mammal; separating a plurality of monocytes from the bone marrow; labeling the monocytes with biotin-conjugated lineage panel antibodies to one or more lineage surface antigens; removing of monocytes that are positive for the lineage surface antigens from the plurality of monocytes, and recovering a Lin− HSC population containing EPCs. Isolated Lin− HSCs that have been transfected with therapeutically useful genes are also provided, and are useful for delivering genes to the eye for cell-based gene therapy. Methods of preparing isolated stem cell populations of the invention, and methods of treating ocular diseases and injury are also described.

The invention relates to a preparing method of a photoelectrochemical sensor based on sandwich cardiac troponin T marked by Ag2Se@CdSe and application, and belongs to the technical field of novel functional materials and biosensing detection. According to concrete contents of the preparing method and the application, CeO2-TiO2 composite nanometer materials with photoelectrocatalytic activity are used as optical activity substrate materials; Ag2Se@CdSe is used as an antibody marker; the sandwich photoelectrochemical sensor is prepared through the signal amplification effect of the marker Ag2Se@CdSe on the substrate materials, and is used for the high-sensitivity detection of the cardiac troponin T of myocardial damage specific marker. The method has the important significance on the early diagnosis and treatment of acute myocardial infarction.

The invention discloses a nucleic acid detection method based on the polymer electrochemiluminescence signal amplification technology. The method comprises the following steps: synthesizing and activating ruthenium terpyridine, preparing a polylysine-ruthenium terpyridine compound, marking the polylysine-ruthenium terpyridine compound with a DNA (deoxyribonucleic acid) probe, and magnetically capturing and detecting a target DNA sequence. According to the method, the polymer electrochemiluminescence signal amplification technology is applied to nucleic acid detection, and an organic polymer such as polylysine is good in physical and chemical properties and can be applied to the field of electrochemiluminescence signal amplification; polylysine is adopted as a connecting framework for ruthenium terpyridine signal amplification, and the system is stable, hard to aggregate and easy to store; the polylysine-ruthenium terpyridine compound marked with the DNA probe is stable in properties and convenient to modify and store. The method is easy in operation, quick, stable and controllable, is suitable for nucleic acid detection and can serve as an antibody labeling method in immunoassay to improve the sensitivity.

The invention provides a CRP latex-reinforced immunonephelometry reagent. The CRP latex-reinforced immunonephelometry reagent comprises CRP antibody-labeled latex particles, a buffer, a surfactant, an inorganic salt, a stabilizing agent, a suspending assistant, an excipient and an antiseptic. The invention also provides a kit for single-reagent CRP latex-reinforced immunonephelometry and a use thereof. The CRP latex-reinforced immunonephelometry reagent has simple composition, can be used simply and conveniently, has a fast reaction rate, high sensitivity and good repeatability, can be operated by a simple apparatus, has a wide apparatus adaptation range, has a low cost, can be widely used in large, middle and small hospitals and is suitable for clinical fast infection diagnosis and infection prognosis evaluation.

An optical biological detector is able to bind specific targeted bacterial cells by stamping an antibody grating pattern onto a silicon surface. The antibody grating alone produces insignificant optical diffraction, but upon immunocapture of the targeted cells, the optical phase change produces a diffraction pattern. Micro-contact printing provides a method for placing the antibody grating pattern directly onto a substrate surface with no additional processes or binding chemicals. Antibodies or other biologically active material may be stamped directly onto clean native oxide silicon substrates with no other chemical surface treatments. Direct binding of the antibodies to the silicon occurs in a way that still allows them to function and selectively bind antigen. The performance of the sensor was evaluated by capturing Escherichia coli O157:H7 cells on the antibody-stamped lines and measuring the intensity of the first order diffraction beam resulting from the attachment of cells. The diffraction intensity increases in proportion to the cell density bound on the surface.

The invention relates to a preparation method and application of a pancreatic cancer immunosensor based on gold electrodeposition and Au@Ag / CuO-GS as markers, and particularly relates to preparation of a sandwich-type electrochemical immunosensor for detecting pancreatic cancer tumor markers by adopting Au@Ag / CuO-GS as a detection antibody marker. By using excellent biocompatibility and high catalytic performance of the Au@Ag / CuO-GS, the prepared sensor has relatively high sensitivity and relatively wide detection range; and the detection limit can reach 1.5fg / mL.

The invention relates to a quantum dot fluorescent probe and application thereof. The invention is characterized in that the quantum dot fluorescent probe utilizes a difunctional cross-linking agent long-chain succinimidyl-4-[N-maieimidomethyl]cyclohexane-1-carboxy-[6-amidocaproate] (SMCC) to undergo a cross-linking reaction with an amino group on the surface of an amino quantum dot; a maleimide group is produced on the surface of the quantum dot; a to-be-labeled antibody is reduced by a reducing agent dithiothreitol (DTT) so as to reduce a disulfide bond into a mercapto group; and the mercapto group and the maleimide group form a covalent bond so as to realize labeling of the quantum dot with the antibody. The quantum dot fluorescent probe is applied to (1) detection of one protein oncofetal antigen or (2) detection of a plurality of protein CEA, euron-specific enolase (NSA) and a cytokerain fragment 19CYFRA21-1, wherein the detection limit of detection (1) is 38 pg / ml, and the detection limit of detection (2) is 0.9 ng / ml.

The invention belongs to the technical field of nano functional materials, immunoassay and biosensing, and provides a preparation method and application of an immunosensor established based on a manganese dioxide loaded silver nanoparticle multiwalled carbon nanotube. The electrochemical immunosensor which is prepared by taking the manganese dioxide loaded silver nanoparticle multiwalled carbon nanotube AgNPS@MnO2@MWCNTs as a detection antibody marker has the advantages of high specificity, high sensitivity, low detection limit and the like, and has significant scientific meanings and application values in detection on carcino-embryonic antigen CEA and alpha fetoprotein AFP.

The invention provides an immunochromatographic assay system. The system comprises a housing and a laser light source, a test strip mounting base, a chromatographic test strip and a camera arranged inthe housing; the chromatographic test strip is placed on the test strip mounting base, the light produced by the laser light source is used to irradiate the chromatographic test strip, and the camerais used to capture a fluorescent signal generated after the chromatographic test strip is irradiated. According to the immunochromatographic assay system of the invention, the laser light source is used to irradiate quantum dot microspheres that are labeled by detection antibodies of various biomarkers and have different colors, a plurality of biomarkers can be simultaneously detected at one timeand imaged for data analysis, and the detection process is accurate and efficient. Based on the operation, the invention also provides a sample imaging method and a sample image analysis method basedon the above immunochromatographic assay system.

The invention discloses a method of detecting ochratoxin A in cereals by means of a nano antibody and immunomagnetic separation. The method includes the steps of: 1) combining anti-OTA nano antibody with nano immunomagnetic beads to prepare IMB, and enriching the OTA in the cereals by means of the IMB to prepare a pretreated sample; 2) with dot immunization method, immobilizing an OTA-OVA detection antigen on a PVDF film, wherein the immunomagnetic beads are subjected to an immune-reaction in the form of antibody marker, the OTA-OVA and the to-be-tested substance, OTA, are combined with the antibody competitively so as to determine whether the immunomagnetic beads are aggregated on the PVDF film or not, thereby obtaining a detection result. The method achieves simple and quick qualitative detection. An operator can read the result just by naked eyes without any analysis instrument. Furthermore, the method can be used for developing a novel quick and visible detection card for specially detecting the OTA in the cereals.

The invention discloses preparation and application of an adjacent hybridization dual-mode immunosensor based on MXene nanosheet photo-thermal amplification. Polyethyleneimine (PEI) modified TiO2 disc-shaped nanoparticles are used as a substrate, and a large amount of capture substrate deoxyribonucleic acids are fixed on a sensing interface through electrodeposition of gold. Two deoxyribonucleic acid probes are both labeled with a human epididymis protein 4 (HE4) antibody of a target object, and after the deoxyribonucleic acid probes as a recognition part of HE4 are captured by DNA3, the HE4 induces adjacent hybridization between primary antibody-labeled DNA1 and secondary antibody-labeled DNA2 by immunorecognition. An MXene nanosheet is loaded with a large amount of thionine, so that theMXene nanosheet can be effectively intercalated into a double-stranded DNA groove formed by hybridization, can be used as a signal probe for electrochemical-temperature dual modes, and realizes amplification of electrochemical signals due to temperature rise generated by the photo-thermal effect. Under the irradiation of an 808 nm infrared laser device, high-sensitivity detection of the HE4 is realized.

The invention provides a fluorescent protein and / or coupled protein monoclonal antibody labeling method and a kit thereof. The preparation method comprises the following steps: firstly, carrying out desalination treatment on fluorescent protein and / or coupled protein, blocking sulfydryl of the fluorescent protein and / or coupled protein by adopting NEM, and carrying out cross-linking reaction on the fluorescent protein and / or coupled protein NEM and S-SMCC; meanwhile, cross-linking SLCSPDP and the monoclonal antibody, reducing disulfide bonds of the monoclonal antibody through TCEP, and conducting sulfhydrylation on the monoclonal antibody; and finally, carrying out cross-linking reaction on the sulfhydrylated antibody and NEM-fluorescent protein and / or coupled protein-S-SMCC. Directional coupling of the fluorescent protein and / or the coupling protein and the monoclonal antibody is achieved, the cross-linking efficiency of labeling of the fluorescent protein and / or the coupling proteinand the monoclonal antibody is improved, the specificity of labeling of the fluorescent protein and / or the coupling protein and the monoclonal antibody is further improved, and a fluorescence signal is enhanced.

The invention relates to immunochromatography technologies, and aims at providing a bigeminy qualitative fungaltoxin colloidal gold immunochromatography test strip and a preparation method. The test strip comprises a black strip-like polyvinyl chloride backboard taken as a base material, wherein the surface of the test strip is successively provided with a sample pad, a colloidal gold antibody marker fixing pad, a nitrocellulose membrane and an adsorption pad along the length direction of the backboard, and the adjacent pad or the membrane are in overlap joint with each other; and the nitrocellulose membrane is provided with two detection lines and one quality control line which have the same width with that of the backboard and are separated from one another, wherein the quality control line is positioned between the two detection lines. According to the test strip provided by the invention, the colloidal gold, the cost of which is relatively low, is adopted as an antibody marker, a competition method principle is adopted to quickly detect fungaltoxin, the nitrocellulose membrane wraps the two detection lines simultaneously, the color depth can be compared by naked eyes, and qualitative detection can be carried out quickly on two kinds of fungaltoxin simultaneously. The chromatography test strip prepared has excellent sensitivity and stability, and is easy, convenient and fast to operate and low in cost, thereby being particularly suitable for rapid diagnosis on site.