30 results about "Fluorescent polarization" patented technology

The invention relates to an aptamer specifically combined with beta-lactoglobulin and application of the aptamer, and belongs to the technical field of biological detection. According to the aptamer and the preparation method thereof, a binding domain base, participating in recognition, of the aptamer is predicted through molecular docking firstly, then the binding domain base is subjected to directional mutation, the aptamer with the recognition performance improved is obtained, the affinity of the aptamer to beta-lactoglobulin is 10.6 nM, and the aptamer has no recognition capacity on alpha-lactalbumin, casein, bovine serum albumin, immune globulin G, lactose and the like and can be used for preparing the aptamer with the recognition performance improved. Therefore, the aptamer disclosed by the invention has good sensitivity and specificity on the beta-lactoglobulin. On the basis, a fluorescence polarization method is directly constructed by utilizing the characteristic that the beta-lactoglobulin is a biomacromolecule, when the beta-lactoglobulin exists, an aptamer marked by a fluorophore FAM recognizes the beta-lactoglobulin to form an aptamer beta-lactoglobulin compound, and the fluorescence polarization value is relatively large, so that the beta-lactoglobulin compound can be used for identifying the beta-lactoglobulin. Therefore, the specific detection of the low-concentration beta-lactoglobulin is realized.

A degree of polarization of second reference samples produced by adding an antibody, a tracer, and a target substance having mutually different concentrations to a first reference sample not including the target substance is corrected with a degree of polarization of the first reference sample to generate a first calibration curve. A degree of polarization of a second sample to be measured produced by adding the antibody and the tracer to a first sample to be measured in amounts equal to those added to the second reference samples is corrected with a degree of polarization of the first sample to be measured to obtain the concentration of the target substance in the first calibration curve.

The present invention discloses an immunofluorescence polarization analyzer with a multi-sample detection function, and relates to the technical field of fluorescence polarization analyzers, the immunofluorescence polarization analyzer comprises a cover, an outer casing and a bottom plate, the bottom plate, the outer casing and the cover are sequentially arranged from bottom to top, the inner part of the outer casing is connected with a damping cage through a plurality of damping mechanisms, the damping cage is provided with a test tube rack, and the test tube rack is connected with the bottom plate. The test tube rack extends out of the top of the outer machine shell, a plurality of sample test tubes are arranged in the test tube rack, a transmitting assembly is installed on the test tube rack, a magnetic cover is arranged at an opening of each sample test tube, a detection assembly is installed in the damping cage, and each damping mechanism is further used for oscillating a sample. Before detection is started, the damping mechanism firstly conducts final oscillation on the sample test tube before detection, then the detection assembly detects a sample in the sample test tube, the damping mechanism keeps the sample test tube stable in the detection process, and the detection precision is improved.

The present disclosure relates to a method of determining the concentration of a plasma protein in a sample using fluorescence polarization, wherein the sample is in an assay solution comprising a neutral hydrophilic polymer.

This invention discloses a high-throughput screening method for monkeypox virus (MPXV) N7-methyltransferase (N7-MTase) inhibitors based on fluorescence polarization technology and its application. This method uses MPXV E1... CTD Using the / E12 protein complex as a target, and leveraging the specific binding characteristic of the fluorescent probe FL-NAH to the target catalytic center, small molecule inhibitors that competitively bind to the SAM binding site are screened by monitoring changes in fluorescence polarization signals. This invention yielded a series of candidate compounds with significant inhibitory activity. Experiments demonstrated that these inhibitors exhibit strong inhibitory effects on MPXV N7-MTase, with a biochemical IC50 level of [missing information]. 50 Preferably, the concentration can reach 4.65 μM; at the cellular level, the compound exhibits a clear attenuation effect against poxviruses, with an EC50 value of [missing value]. 50 The range is up to 46.75 μM, and it has low cytotoxicity (CC). 50 >200 μM).

The application discloses a functional nucleic acid probe and a preparation method and application thereof. The preparation method comprises the following steps: forming a DNA sheet by self-assembly of a first DNA single strand and a second DNA single strand, and then combining the DNA sheet with a molecular beacon probe to prepare the functional nucleic acid probe; wherein the end of the first DNA single strand and the end of the second DNA single strand are complementary to each other; and the molecular beacon probe comprises an aptamer sequence of foodborne pathogenic bacteria. The fluorescence polarization method based on the functional nucleic acid probe provided by the application has the advantages of high sensitivity, strong specificity, short detection time and the like, and can be used for self-immediate monitoring of the content of foodborne pathogenic bacteria in drinking water or the content of foodborne pathogenic bacteria in environmental water, and has great application value and market value in family health and environmental protection and the like.

The application discloses a KRAS small-molecule fluorescent probe and a preparation method and application thereof, a structural general formula of the KRAS small-molecule fluorescent probe is shown as formula (I), and the fluorescence polarization activity determination method based on the small-molecule fluorescent probe has the advantages of simple test system, less required protein types, low dosage, no need of a complex buffer system, small influence of time and solvent and the like compared with HTRF. The method can be used for screening of KRAS wild type and various mutant inhibitors including but not limited to G12C, G12V, G12D, G12A, G12S and G12R, and has a good application prospect.

A method of fluorescence polarization for measuring antibody concentration in a sample is disclosed. The method includes performing a measurement period, measuring a first set of sampled phases of fluorescence polarized in a first polarization direction and a second set of sampled phases of fluorescence polarized in a second polarization direction. At least one sampling phase of the fluorescence polarized in the second polarization direction occurs between the sampling phases of the fluorescence polarized in the first polarization direction. The method includes calculating a first value for a first set of sampled phases and calculating a second value for a second set of sampled phases. The method includes determining an antibody concentration based on a function of the first value and the second value.

The invention belongs to the technical field of fluorescent probes, and particularly discloses a novel fluorescent compound capable of being combined with a retinoic acid receptor related orphan receptor gamma normal site and application of the novel fluorescent compound serving as a fluorescent probe to inhibitor screening, imaging and the like. Compounds P1-P11 conforming to the general formula (I) are synthesized, a novel ROR gamma normal inhibitor screening platform can be established on the basis of a fluorescence polarization probe system constructed by the compounds according to a competitive ligand replacement principle, and the technical scheme breaks through the limitation of a traditional activity detection method and has a wide application prospect. An activity evaluation tool with economical efficiency, timeliness and reliability is provided for research and development of drugs targeting ROR gamma normal sites, and the lead compound discovery and structure optimization process can be accelerated.

The invention discloses a polypeptide probe fluorescent biosensor for detecting an ERRgamma active substance, which adopts a polypeptide probe containing an ERRgamma co-activator conserved sequence as an element for identifying an activated state ERRgamma, and realizes high-sensitivity detection of the ERRgamma active substance by virtue of a signal of a fluorescence labeled molecule. In the operation process, the activated state ERRgamma recruits and is combined with the polypeptide probe marked with the fluorescent molecules, and after a chemical substance to be detected is added, the inhibited state ERRgamma is separated from the polypeptide probe marked with the fluorescent molecules. By detecting and comparing the fluorescence polarization values of the system before and after the chemical substance to be detected is added, the detection of the ERRgamma active substance is realized. The fluorescent biosensor disclosed by the patent can simulate a biological action process, and can quickly detect and evaluate known and unknown ERRgamma active substances. The sensor has the remarkable advantages of low cost, high sensitivity, good selectivity, simplicity and convenience in operation, high response speed, convenience in on-site instant detection and the like, is expected to promote technical development in the field of pollutant sensing detection, and has important significance in commercialization and practical application.

The application belongs to the technical field of biological medicine, and particularly relates to an aminoglycoside phosphotransferase cyclic peptide inhibitor and use thereof. APH is a key enzyme capable of causing inactivation of aminoglycoside antibiotics. Based on phage display technology, a series of polypeptides containing two cysteine residues are successfully screened, and candidate cyclic peptide molecules are generated after modification by a chemical cross-linking agent. The results of fluorescence polarization analysis and enzyme activity determination show that the binding affinity of the cyclic peptide molecules to the target protein APH reaches the nanomolar level or the low micromolar level, and the catalytic activity thereof can be significantly inhibited. The development of the cyclic peptide inhibitors provides a new research basis for further optimization and clinical application of APH targeted drugs.

The invention discloses a double-near-sine gold grating microstructure with photo-thermal heating and fluorescence polarization detection enhancement functions and a preparation method and application thereof, and the double-near-sine gold grating microstructure comprises a substrate and a double-near-sine type gold grating periodic array structure arranged on the substrate in an array mode. The minimum repetitive unit of the double-nearly-sinusoidal gold grating periodic array structure is a double-nearly-sinusoidal gold grating unit, and the double-nearly-sinusoidal gold grating unit comprises two parallel nearly-sinusoidal gold strips with sinusoidal waveform or quasi-sinusoidal waveform and different amplitudes. The double near-sine gold grating microstructure provided by the invention has the advantages of high integration (a heat source and a detection substrate are combined into one, the system structure is greatly simplified, and implementation of a chip laboratory is facilitated), rapidness and high efficiency (the photothermal conversion efficiency is high, the thermal response is fast, and the heating / cooling rate far exceeding that of a traditional PCR instrument), high sensitivity, low cost, low power consumption, good compatibility and the like.

The application discloses a rigid response fluorescence polarization biosensor for detecting AFB1 and application. The rigid response fluorescence polarization biosensor comprises a target recognition unit, the target recognition unit comprises an aptamer-complementary chain double-stranded complex which specifically recognizes AFB1; a signal amplification unit, the signal amplification unit comprises a rolling circle amplification reaction system; a signal conversion unit, the signal conversion unit comprises a CRISPR / Cas12a detection system; and a signal output unit, the signal output unit comprises a conformational restriction depolarization reporter, and the conformational restriction depolarization reporter is a single-stranded DNA / double-stranded DNA complex structure. The application realizes quantitative detection of AFB1 by using FP value change, has the advantages of low detection limit, strong specificity, strong anti-matrix interference capacity, simple operation and the like, and can be widely applied to rapid and high-sensitivity detection of AFB1 in complex samples such as grains, foods and feed.

This disclosure relates to the field of anticancer drug technology, and discloses a 7-azaindole compound, its synthesis method, and its uses. The structure of the 7-azaindole compound is as follows: This 7-azaindole compound can be used as a fluorescent polarization probe or a degradation chemical probe targeting CSN5; wherein, the fluorescent polarization chemical probe has a good binding affinity to the metalloproteinase CSN5, laying an important foundation for the discovery of novel CSN5 inhibitors; at the same time, the degradation chemical probe exhibits good enzyme-level activity and cell-inhibitory activity, and has the potential to degrade CSN5 protein and its variants, providing a material basis for the development of related drugs targeting CSN5 and the study of its biological functions, and also has great potential in the discovery of cancer immunotherapy drugs and the treatment of other related diseases.

To provide a supporting body having a plurality of reaction parts for performing fluorescent polarization immunoassay to measure a target substance in a sample.SOLUTION: A fluorescent polarization immunoassay supporting body includes: a reaction part for carrying an antibody and a fluorescent-labeling substance. A first fluorescent polarization immunoassay supporting body includes a reaction part for serving as a microchannel. A second fluorescent polarization immunoassay supporting body includes a reaction part for serving as a recess, with some of the reaction parts being connected through a communication passage.SELECTED DRAWING: Figure 1

A method for determining activity of an acyl transferase enzyme, the method comprising: (i) preparing a reaction mixture comprising: (a) an acyl transferase enzyme, (b) a peptide substrate bound to a fluorophore, wherein the substrate is a cysteine-containing oligopeptide of 5-25 amino acids in length, (c) an acyl-CoA, and (d) a detergent comprising micelles, wherein the acyl transferase enzyme mediates acylation on a cysteine of said peptide substrate to result in association of the peptide with micelles of the detergent with resultant increase in fluorescence polarization; and (ii) measuring fluorescent signal of the reaction mixture; wherein an increase in fluorescence polarization of the reaction mixture compared to fluorescence polarization of a control reaction indicates acyl transferase activity of the acyl transferase enzyme. The above assay method may also be used for screening compounds for their ability to act as inhibitors of an acyl transferase enzyme.

The invention relates to the technical field of component design, in particular to a benzene ring acid group substitution type screening method based on isoamyl cinnamate and application of the benzene ring acid group substitution type screening method based on isoamyl cinnamate. The screening method comprises the steps that a virtual substituent library is established, acid group substituents are introduced to an isoamyl cinnamate benzene ring, and a plurality of substitution combinations are generated; predicting a minimum value pKai of an acid dissociation constant and a polar atom ratio PAR for each structure, and screening less than or equal to 50 candidate structures according to the minimum value pKai and the polar atom ratio PAR; measuring the fluorescence polarization anisotropy r of each candidate structure, and screening the first 50% of samples according to the sequence of r values from small to large; sequentially measuring the quantum dot fluorescence intensity retention rate Fret and the coating UVB retention rate RAUVB of the screened samples; and outputting the acid group substitution type corresponding to the maximum value according to the product sequence of the two. The self anti-ultraviolet attenuation capability and the photosensitive component protection effect are reflected, and the optimal structure is ensured to have self stability and synergistic protection performance in a real compound system.

The application discloses a high-throughput screening method for anti-gastric cancer drugs. The application constructs a high-throughput screening method for anti-gastric cancer drugs, which is based on fluorescence polarization technology to screen small molecule inhibitors for inhibiting the interaction between SOS1 and GRB2, and the small molecule inhibitors for inhibiting the interaction between SOS1 and GRB2 have the potential to prepare drugs for treating gastric cancer. Through the high-throughput screening method for anti-gastric cancer drugs, the screening efficiency of the anti-gastric cancer drugs is improved, and the digitalis saponin is verified by experiments to have the anti-gastric cancer effect as a potential anti-gastric cancer drug candidate. The digitalis saponin has the ability to inhibit the interaction between SOS1 and GRB2. The finding provides a new direction and possibility for developing gastric cancer treatment drugs and brings more treatment options for gastric cancer patients.

The invention discloses a retinoic acid X receptor alpha activation effect molecule detection method based on a fluorescence polarization technology, and belongs to the technical field of biological analysis. According to the method, the change of a probe fluorescence polarization signal caused by the change of the binding state of the RXR alpha and the fluorescent nuclear receptor co-regulatory peptide is directly monitored, so that the rapid evaluation of the to-be-detected substance on the receptor activation effect is realized. According to the method, three core processes of background signal determination, to-be-detected substance signal detection and statistical analysis are completed on the molecular level by virtue of a conventional multifunctional microplate reader, so that the dependence on high-cost equipment or a complex cell model in the prior art is effectively avoided, and high efficiency, low cost and high flux of RXR alpha activator screening are realized. The method is suitable for early warning of toxicity of environmental compounds and efficient screening of RXRalpha targeted drugs, and a practical tool is provided for receptor function research and drug development.

A fluorescence polarization measurement device includes a light source unit, a polarization direction modulation element, a detector, and a controller. The polarization direction modulation element spatially modulates a polarization direction of the excitation light by a predetermined frequency, and emits, on a measurement target solution, the excitation light for which the polarization direction is spatially modulated by the predetermined frequency. The detector detects a spatial distribution of fluorescence intensity of the fluorescence having a polarization direction in a predetermined direction from among fluorescence emitted from the measurement target solution due to the excitation light. The controller extracts, from the detected spatial distribution of fluorescence intensity, a direct current component and a component having a frequency identical to the predetermined frequency, and calculates, based on the extracted component and the direct current component, a degree of polarization of the measurement target solution.

This invention relates to a class of small molecule fluorescent probes targeting the SOS1 protein and their use in detecting protein binding activity. The fluorescent probes have the general structural formula shown in formula (I). R1 ​​is selected from hydrogen, halogen, C1-C3 alkyl, or C1-C3 alkoxy groups; R2 is a linking group selected from C3-C8 alkylene groups, heteroalkyl chains containing 1-3 heteroatoms, or polyethylene glycol fragments. This series of probes exhibits sub-micromolar dissociation constants for the SOS1 protein and its catalytic domains. This invention further provides a preparation process for the probes and a SOS1 inhibitor screening system based on fluorescence polarization technology. These probes support high-throughput, homogeneous, and real-time monitoring of SOS1 binding activity, and have significant application value in the fields of antitumor drug development and lead compound screening.

Disclosed are a calibration curve creation method, a fluorescence polarization immunoassay method, a fluorescence polarization immunoassay device, and a calibration curve creation kit. The calibration curve creation method uses an antibody that binds to a target substance and a fluorescently labeled substance that labels the target substance with a fluorescent dye. The degree of fluorescence polarization Pconc of the sample conc is created on the basis of the degree of fluorescence polarization P0 of a first reference sample free of the target substance and a calibration curve in which the concentration of the target substance added exceeds the concentration CS alpha of the target substance, creating the calibration curve.

The application discloses a BCL6 small-molecule fluorescent probe and a preparation method and application thereof. The compound provided by the application has fluorescent characteristics and has good specific binding to BCL6. The compound is used as a fluorescent polarization probe, and through a competition method, screening of a BCL6 ligand and evaluation of a ligand affinity level can be realized. The BCL6 small-molecule fluorescent probe provided by the application provides a basis for subsequent high-throughput screening of a drug design targeting BCL6-BTB.

A method for high-throughput screening of anti-gastric cancer drugs. A small molecule inhibitor that inhibits an interaction between SOS1 and GRB2 is screened on the basis of a fluorescence polarization technique. The small molecule inhibitor that inhibits the interaction between SOS1 and GRB2 has potential for the preparation of a drug for treating gastric cancer. By means of the method for high-throughput screening of anti-gastric cancer drugs, the screening efficiency for the anti-gastric cancer drugs is improved. Digitonin, as a potential candidate for the anti-gastric cancer drugs, is experimentally validated to have an anti-gastric cancer effect and the ability to inhibit the interaction between SOS1 and GRB2.

The invention discloses a fluorescence polarization immunoassay and a fluorescence labeling substance. A fluorescence polarization immunoassay using a fluorescently labelled substance in which a single domain antibody is labelled with a fluorescent dye. A fluorescently labeled substance obtained by labeling a single domain antibody (e.g., a VHH antibody or a vNAR antibody) having binding ability to a target substance with a fluorescent dye is used. The fluorescence polarization immunoassay includes a binding step for binding a fluorescently labeled substance to a target substance; and a measurement step for measuring a change in fluorescence polarization of the fluorescently labeled substance bound to the target substance.

The invention relates to a screening method of a deproteinizing enzyme inhibitor and an inhibitor obtained through screening, and belongs to the technical field of biological medicine. The invention provides a method for efficiently screening a deproteinizing enzyme inhibitor, which comprises the following steps of: detecting fluorescence signal change after a compound to be detected and deproteinizing enzyme are incubated through a fluorescence polarization method by using an E. probe UFM1-Lys-TAMRA obtained through Lys-TAMRA fluorescence labeling as a substrate, calculating an inhibition ratio, and quickly screening a potential inhibitor. The compounds BAY 11-7082 and PR-619 screened by the method are used as deproteinization enzyme inhibition, wherein the BAY 11-7082 can be used for effectively reducing the level of intracellular Euclidinylation within the concentration range of 2.5-10 [mu] M. The invention solves the problem of lack of deproteinization enzyme inhibitors and high-throughput screening methods thereof, and provides a new tool and strategy for research of an EK modification system and development of drugs for treating related diseases.

The invention relates to the technical field of biomedical treatment, and discloses a method for high-throughput screening of MHC-II polymer antigen peptide. Comprising the following steps: carrying out thrombin excision on an MHC-II compound, in the presence of HLA-DM, displacing a fluorescently-labeled intermediate peptide into an antigen binding slot of the MHC-II compound to form an FAM-MHC compound, co-incubating the FAM-MHC compound, to-be-screened antigen peptide and HLA-DM at 37 DEG C, detecting fluorescence polarization values at different time points, and judging the binding strength of the antigen peptide to be detected and the MHC-II molecule according to the read fluorescence polarization value, thereby realizing the effect of judging the antigen peptide of the MHC-II polymer. By means of an intermediate peptide replacement-fluorescence signal conversion mechanism, the competitive binding strength of the antigen peptide is converted into a fluorescence signal, marker sites do not need to be optimized one by one for different antigen epitopes, and efficient batch screening of the new antigen epitopes can be achieved only by conducting single fluorescence modification on the intermediate peptide.

Methods and reagents for processing samples for fluorescence analysis. Processing methods include treating samples containing riboflavin to reduce riboflavin-dependent autofluorescence by adding riboflavin binding protein to the sample, irradiating the sample, or a combination thereof. Processing methods also include clarifying samples by coagulating, precipitating, and / or otherwise removing proteins and other components that interfere with fluorescence analysis without removing the analyte. Fluorescence analysis methods include fluorescence polarization analysis (FPA) and others. Reagents suitable for performing the disclosed methods are provided.

To provide a calibration curve creation method capable of creating a more accurate calibration curve across a wide range from a low-concentration region to a high-concentration region, as well as a fluorescence polarization immunoassay, a program, a fluorescence polarization immunity measuring apparatus, and a calibration curve creation kit that use this calibration curve.SOLUTION: A calibration curve creation method is a method of creating a calibration curve for a fluorescence polarization immunoassay using an antibody having a binding ability to a target substance and a fluorescent-labeled substance obtained by labeling the target substance with a fluorescent dye, and creates the calibration curve on the basis of a fluorescence polarization degree P0 of a first reference sample that does not contain the target substance, and a fluorescence polarization degree Pconc of a calibration curve creation sample conc in which a concentration of the added target substance exceeds a concentration CSα of the target substance.SELECTED DRAWING: Figure 6