14 results about "Affinity constant" patented technology

The invention relates to the technical field of biology, and particularly discloses a cronobacter sakazakii nucleic acid aptamer and application thereof in preparation of a biosensor. According to the invention, a nucleic acid aptamer with a DNA sequence as shown in SEQ ID No: 1 is designed for Cronobacter sakazakii MipA protein, and 5'terminal amino is modified. The aptamer can be used for constructing a fluorescence quenching type biosensor, and comprises a fluorescent probe (fluorescent nanoparticles synthesized by citric acid diammonium, thiourea, tetramethyl orthosilicate and cerium dioxide, and a first aptamer modified by carboxyl) and a quenching probe (citric acid reduced gold nanoparticles, a second aptamer modified by sulfydryl, SEQ ID No: 2). Compared with a traditional method, the screening efficiency is remarkably improved, and the detection time is lt; the method has the advantages of high sensitivity, high interference resistance and affinity constant of 13.28 nM, is suitable for rapid monitoring of infant food, and reduces the economic cost by at least 40%.

The application provides an anti-aflatoxin B1 monoclonal antibody and application, and particularly relates to an anti-aflatoxin B1 monoclonal antibody containing only a heavy chain variable region, a nucleotide coding the antibody, an expression vector carrying the monoclonal antibody or a nucleotide sequence coding the monoclonal antibody. The application screens and prepares an antibody for aflatoxin B1 from a phage nanobody synthesis library and applies the antibody to detection or identification of aflatoxin B1. The affinity constant of the antibody is 1.96E-07, the antibody can effectively detect aflatoxin B1, and can be identified from other common fungal toxins.

The present application relates to an assay method using affinity crosslinking of DNA-linked ligands to proteins to enable small molecule screening and determination of apparent affinity constants of ligands to the proteins. This method has been applied to determine 96 compounds' dissociation constants to a protein target simultaneously, and directly determine a compound's IC50 against five protein targets concurrently in crude cell lysates. Additionally, this approach was used to screen a Library of Pharmacologically Active Compounds (LOPAC) library against dihydrofolate reductase (eDHFR), enabling the discovery of a novel eDHFR inhibitor (IC50=7.9 μM). An assay kit and the method of uses are within the scope of this disclosure.

This invention utilizes a machine learning model to analyze the crystal structure of the PEDV Nsp5 protein. Through virtual peptide screening technology, a peptide sequence with potential affinity for the target protein, YKKLHK(162860), was artificially synthesized in a solid phase. Using artificially expressed PEDV Nsp5 protein, the peptide was screened using an ELISA assay. The affinity constant between the peptide and the target protein was determined using surface plasmon resonance (SPR) assays. The cytotoxicity of peptide 162860 was tested using a CCK-8 assay kit. Its inhibitory activity against viral infection was tested using quantitative real-time PCR and indirect immunofluorescence assays. The results showed that the 162860 sequence significantly inhibited PEDV infection.

The application is used for analyzing the S1-CTD region of the PEDV S protein crystal structure by means of a machine learning model, and a polypeptide sequence FWKSKR (110766) with potential is screened from the target protein by polypeptide virtual screening technology. The 110766 sequence is artificially synthesized on a solid phase, and the polypeptide is screened by means of ELISA experiment using artificially expressed PEDV S1 protein. The affinity constant of the polypeptide and the target protein is identified by means of surface plasmon resonance experiment (SPR). The cytotoxicity of the polypeptide 110766 is tested by CCK-8 kit. The virus infection inhibiting activity of the polypeptide is tested by means of fluorescent quantitative PCR and indirect immunofluorescence experiment. The results show that the 110766 sequence can significantly inhibit the infection of PEDV.

This invention utilizes a machine learning model to analyze the S1-CTD region of the PEDV S protein crystal structure. Through virtual peptide screening, a peptide sequence of FWKEAK (110616) with potential affinity for the target protein was identified. The 110616 sequence was artificially synthesized in a solid phase, and the peptide was screened using ELISA with artificially expressed PEDV S1 protein. The affinity constant between the peptide and the target protein was determined using surface plasmon resonance (SPR) assays. The cytotoxicity of peptide 110616 was tested using a CCK-8 assay kit. Its inhibitory activity against viral infection was assessed using quantitative real-time PCR and indirect immunofluorescence assays. The results showed that the 110616 sequence significantly inhibited PEDV infection.

Disclosed herein are fully human antibody molecules that immunospecifically bind to human IL-5. The antibody molecules can bind to human IL-5 with an equilibrium affinity constant (KD) of at least about 40 pM as determined by surface plasmon resonance.

This invention utilizes a machine learning model to analyze the crystal structure of the PEDV Nsp5 protein. Through virtual peptide screening, a peptide sequence KYRRQH (177080) with potential affinity for the target protein was identified. The 177080 sequence was artificially synthesized in a solid phase, and the peptide was screened using ELISA with artificially expressed PEDV Nsp5 protein. The affinity constant between the peptide and the target protein was determined using surface plasmon resonance (SPR) assays. The cytotoxicity of peptide 177080 was tested using a CCK-8 assay kit. Its inhibitory activity against viral infection was assessed using quantitative real-time PCR and indirect immunofluorescence assays. The results showed that 177080 significantly inhibited PEDV infection.

The invention discloses a nucleic acid aptamer of RUNX2 protein and application of the nucleic acid aptamer, and belongs to the technical field of biology, the nucleotide sequence of the nucleic acid aptamer is shown as SEQ ID NO.1, the nucleic acid aptamer has the advantages of being small in molecular weight, stable in chemical property, easy to store and mark and the like, the nucleic acid aptamer is obtained through screening based on the SELEX technology, the nucleic acid aptamer can be combined with the RUNX2 protein with high affinity and high specificity, and the nucleic acid aptamer can be used for detecting the RUNX2 protein. The affinity constant is as low as 8.88 nM, and the synthesis cost is low. The nucleic acid aptamer provided by the invention shows good application prospects in the aspects of disease detection, diagnosis, molecular imaging, targeted therapy and the like.

A peptide and its sequence that can inhibit PEDV based on virtual screening. This invention utilizes a machine learning model to analyze the S1-CTD region of the PEDV S protein crystal structure. Through virtual peptide screening technology, a peptide sequence with potential affinity for the target protein, WHFNRP (115042), was identified. The 115042 sequence was artificially synthesized in a solid phase, and the peptide was screened using ELISA with artificially expressed PEDV S1 protein. The affinity constant between the peptide and the target protein was identified using surface plasmon resonance (SPR) assays. The cytotoxicity of peptide 115042 was tested using a CCK-8 assay kit. Its inhibitory activity against viral infection was tested using quantitative real-time PCR and indirect immunofluorescence assays. The results showed that the 115042 sequence significantly inhibited PEDV infection.

The invention discloses preparation of an anti-MCR-1 and anti-MCR-2 monoclonal antibody and development and application of a kit of the anti-MCR-1 and anti-MCR-2 monoclonal antibody, and belongs to the technical field of biological detection. The antibody disclosed by the invention can be used for detecting MCR-1 and MCR-2 proteins, and the detection efficiency of polymyxin drug resistance can be properly improved. The screened antibody can be efficiently paired, shows an excellent synergistic effect in a double-antibody sandwich method, and is strong in signal and low in background. Through surface plasmon resonance detection, the affinity constants of the antibody to MCR-1 and MCR-2 proteins reach a nanomole level, high sensitivity of detection is ensured, the detection limit of recombinant proteins can reach 0.01 ng / mL, and the detection limit of bacteria can reach 104 CFU / mL. The whole detection process only needs 10-15 minutes, the operation is simple, professional equipment and training are not needed, and the method is very suitable for on-site rapid screening. The kit is simple in component, low in production cost and easy to produce and popularize on a large scale.

The application provides an aflatoxin B1 antibody and application, and particularly relates to an aflatoxin B1 antibody containing only a heavy chain variable region, a nucleotide coding the antibody, an expression vector carrying the aflatoxin B1 antibody or a nucleotide sequence coding the same. The application screens and prepares an antibody for the aflatoxin B1 from a phage nanobody synthesis library and applies the antibody to detection or identification of the aflatoxin B1. The affinity constant of the antibody is 4.19E-09, the antibody can effectively detect the aflatoxin B1, and can be identified from other common fungal toxins.

The present application relates to the technical field of industrial data analysis, in particular to a textile dyeing production quality prediction method based on data recognition, comprising the following steps: extracting dye molecule affinity constant, salt concentration parameter and temperature parameter, solving according to a thermodynamic adsorption model to generate equilibrium adsorption amount distribution data; extracting dye vat replenishment amount, roller pressure and cloth running speed in the continuous pad dyeing color changing production link. In the present application, space for adjusting liquid discharge can be reserved before the pollution peak approaches the processing limit, and single quality prediction can be expanded to comprehensive judgment considering product quality stability, degraded cloth length control, workshop color changing rhythm coordination and back-end processing load balancing, so that it is more beneficial to compress the quality fluctuation range, reduce the impact of invalid liquid discharge, reduce the mutual interference caused by continuous color changing, and improve the response accuracy of production organization to complex working condition changes in actual production.

The invention provides a one-step screening method for rapidly screening the affinity and the blocking function of the candidate antibody at low cost and high throughput. The method comprises the following specific steps: constructing an antibody gene to be screened in an expression vector, transfecting the vector into cells for expression, optionally using a high-concentration LiCl cell lysis solution to lyse the cells expressing the antibody in the cells, fully curing the antibody in a cell lysis supernatant or a cell culture supernatant by using a BLI sensor, immersing the sensor into an antigen so that the sensor is fully combined with the antibody, and detecting the antibody in the cell lysis supernatant by using the BLI sensor. After balancing, immersing into receptor protein for competitive experiment, and calculating the affinity constant of the antibody and the antigen and the efficiency of blocking the combination of the receptor and the antigen according to the detection signal of the sensor. According to the method, the tedious step of antibody purification in traditional screening is omitted, and the accuracy and the sensitivity which are the same as those of the purified antibody determination affinity and the blocking activity can be achieved; and step-by-step detection of traditional antibody affinity determination and function determination is combined, and the affinity and blocking efficiency data of the antibody can be obtained through one experiment. Meanwhile, the invention discloses a cell lysis solution formula, sample types of the method are expanded to comprise intracellular expression antibodies, BLI is used for determining the affinity of the antibodies and antigens in lysis cell supernatant, and the sensitivity of the cell lysis solution formula is equivalent to that of purified antibodies.