15 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.

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 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.

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.

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.

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.

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 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.