24 results about "Escherichia coli detection" patented technology

The application provides a preparation method of a functionalized phage probe and application of the functionalized phage probe in detection of escherichia coli. The functionalized phage is a recombinant phage (M13KO7@SaBP) in which streptavidin binding peptide (SaBP) is fused and expressed at the N terminal of the main capsid protein P8 protein of M13K07 phage. In the application, the gene encoding SaBP (MDVEAWLGAR) is inserted into the N terminal of the P8 protein gene of M13K07 phage by site-directed mutagenesis to prepare M13K07@SaBP. The stable signal amplification is realized by using the abundant P8 protein (about 2700) of M13 phage and the super strong binding force of biotin-streptavidin, the interference of food sample matrix is reduced by combining the magnetic separation technology, and a detection method of escherichia coli with high sensitivity and small sample matrix interference is constructed.

The invention relates to the technical field of Escherichia coli detection, and particularly discloses a semisolid culture medium for rapid detection of Escherichia coli and a detection method and application thereof, the semisolid culture medium comprises the following components by weight: 4.2-5.8 g / L of agar; 8.5 to 11.5 g / L of tryptone; the semi-solid culture medium comprises the following components: 3.2 to 4.8 g / L of beef extract, 6.5 to 9.5 g / L of lactose, 1.2 to 2.2 g / L of D-glucose, 4.2 to 5.8 g / L of sodium chloride, 42000 to 58000 [mu] g / L of penicillin, 0.12 to 0.28 g / L of cholate, 0.06 to 0.14 g / L of disodium EDTA (Ethylene Diamine Tetraacetic Acid), 0.12 to 0.22 g / L of L-cysteine, 1.2 to 2.8 g / L of yeast extract, 0.005 to 0.015 g / L of vitamin B and an acid-base indicator, the semisolid culture medium and the detection method thereof provided by the invention not only solve the core pain point of the existing escherichia coli detection method in the technical level, but also reduce the operation cost and improve the benefit for enterprises in the economic level, promote the standardization and high efficiency of the food microorganism detection technology in the industry level, and have practicability and industrial popularization value.

The invention belongs to the technical field of harmful microorganism detection, and particularly provides an electrochemical sensor for detecting escherichia coli (escherichia coli O157: H7) in food and a preparation method of the electrochemical sensor. According to the electrochemical sensor, the surface of a substrate electrode is sequentially modified with an electron transduction layer and a recognition molecular layer; wherein the electron transduction layer is formed by an infinite coordination polymer composite material of gold nanoparticles; the recognition molecular layer is a nucleic acid aptamer. The electrochemical sensor is high in sensitivity, good in selectivity and low in detection limit; compared with other detection methods, the method does not need incubation and can be directly used for in-situ and rapid detection of bacteria.

The invention relates to a micro-fluidic chip based on light-cured liquid drops, which comprises an oil phase liquid inlet used for introducing an oil phase containing a photopolymerization initiator and a light-cured monomer; the water phase liquid inlet is used for introducing a water phase containing a test sample, a bacterial lysis reagent and an enzymatic reaction substrate; the liquid drop generation intersection is used for forming water-in-oil liquid drops; the tree-shaped dispersion structure comprises a multi-stage bifurcated micro-channel and an inlet dispersion assembly and is used for realizing preliminary dispersion of liquid drops; the incubation chamber is a flat plate cavity, an internal dispersion assembly is arranged in the incubation chamber, liquid drops are solidified and fixed through an oil phase, bacteria are cracked through a water phase, and a substrate is catalyzed to generate a fluorescent product. The invention also relates to a method for detecting escherichia coli by using the micro-fluidic chip. The water-in-oil liquid drops are cured in situ, the problem that the liquid drops are easy to crack and fuse in incubation is thoroughly solved, the spatial fixity of the cured liquid drops facilitates the positioning collection of fluorescence signals, the signal drift interference in the traditional flowing liquid drop detection is reduced, and the method is suitable for ddPCR technology.

The invention relates to a reagent card box for detecting spirochetes of severe fever with thrombocytopenia syndrome virus, Erhi and Lyme disease, relates to the technical field of molecular biology detection, and comprises a primer probe composition for detecting spirochetes of severe fever with thrombocytopenia syndrome virus, Erhi and Lyme disease, and a kit for detecting spirochetes of severe fever with thrombocytopenia syndrome virus, Erhi and Lyme disease. The primer and the probe for detecting the severe fever with thrombocytopenia syndrome virus comprise a forward primer as shown in SEQ ID NO: 1, a reverse primer as shown in SEQ ID NO: 2 and a probe as shown in SEQ ID NO: 9, the primer and the probe used for Escherichia coli detection comprise a forward primer shown in SEQ ID NO: 3, a reverse primer shown in SEQ ID NO: 4 and a probe shown in SEQ ID NO: 10. The primer and the probe for lyme disease spirochete detection comprise a forward primer of SEQ ID NO: 5, a reverse primer of SEQ ID NO: 6 and a probe of SEQ ID NO: 11. The reagent card box disclosed by the invention adopts a POCT (Point-of-Care Testing) technology to carry out multiple real-time fluorescent PCR amplification detection on nucleic acids of the severe fever with thrombocytopenia syndrome virus, the Escherichia body and the Lyme disease spirochetes, and has timeliness, closeness, accuracy and convenience.

The invention discloses a preparation method of an SERS (Surface Enhanced Raman Scattering) sensor based on oversized annular DNAzyme, a product and application of the SERS sensor in escherichia coli O157: H7 detection, and relates to the technical field of nano materials and biological detection. The SERS sensor disclosed by the invention comprises an aptamer, namely a Key chain-Link chain three-chain body, an LDNAzyme-Block chain double-chain body, an rA Hairpin, an Au-H1 Hairpin probe, an H2 Hairpin probe and an AuNPs-H3 Hairpin probe, and the SERS sensor disclosed by the invention is characterized in that the SERS sensor comprises an aptamer, namely a Key chain-Link chain three-chain body, an LDNAzyme-Block chain double-chain body, an rA Hairpin probe and an AuNPs-H3 Hairpin probe; in the presence of escherichia coli O157: H7, a bimorphic gold nano assembly probe can be formed; the preparation method of the SERS sensor is simple and easy to control, the bimorphic gold nano assembly probe formed after target recognition has a Y-shaped structure with 3D space constraint, the stability is high, the detection operation on escherichia coli O157: H7 is simple and convenient, the sensitivity is high, the detection limit is low, and the specificity is high.

This invention discloses a method and application for detecting F17 Escherichia coli. Using the fimbrial virulence gene ctg_04543 or ctg_04549 of F17 E. coli as a target, a fluorescent quantitative probe is designed based on the nucleotide sequence. Using F17 E. coli genomic DNA as a template, the F17 fimbrial gene ctg_04543 or ctg_04549 is detected by fluorescent quantitative PCR. Based on the fitted standard curve, F17 E. coli in the sample can be quantitatively detected. The F17 E. coli detection method provided by this invention is simple, rapid, quantitative, highly sensitive, and highly specific. It can achieve quantitative detection of F17 E. coli within 2-3 hours, meeting the detection needs of various situations such as laboratory research and animal pathogen diagnosis, and has broad application prospects and extremely high market implementation potential.

The invention relates to the technical field of Escherichia coli detection, and provides Escherichia coli detection equipment and a use method.The Escherichia coli detection equipment comprises an equipment body and a top cover, a protection plate is fixed to the inner wall of the top of the equipment body, and a shaking-up structure is fixed to the inner wall of the bottom of the equipment body; the uniform shaking structure comprises a mounting plate fixed on the inner wall of one side of the bottom of the equipment body, and a driving motor is fixed on one side of the top of the mounting plate. By arranging the uniform shaking structure, the sample tube can be driven to shake at a constant speed under the swinging action of the transverse plate, so that a sample is ensured to be in full contact with a reagent, the concentration of a solution in the sample tube is uniform, the detection accuracy is ensured, and cross contamination caused by long-term retention of a traditional fixed blade in the solution can be avoided; the device has the functions of uniformly mixing a solution and avoiding cross infection during use, and the convenience and the working efficiency of the escherichia coli detection equipment during use are improved.

The application discloses a metal covalent organic framework material, a mediated steady-state electrochemiluminescence sensor and application of the sensor in the field of Escherichia coli detection, wherein the preparation method of the metal covalent organic framework material is as follows: tris(4,4'-dicarboxylic acid-2,2'-bipyridyl) dichlororuthenium, 1,2,4,5-benzene tetraamine tetrahydrochloride and polyphosphoric acid are added into a polytetrafluoroethylene autoclave, heated at 150 DEG C for 24 hours, and then heated at 180 DEG C for another 24 hours to obtain a mixture; after the pH of the obtained mixture is adjusted to 8.5 by using a saturated NaHCO3 solution, black powder is precipitated, the black powder is collected by centrifugation, and the black powder is washed with water, methanol and acetone in sequence by using a Soxhlet extractor for 12 hours; the washed black powder is vacuum dried at 100 DEG C for 6 hours to obtain a ruthenium metal covalent organic framework material; the ruthenium metal covalent organic framework material is used as a signal source of an electrochemical sensor, and a PEG-CS modified interface is constructed on an electrode to enhance the antifouling performance of the sensor in a complex matrix; a molecular amplification method (polymerase chain reaction PCR and HCR) is adopted to fix a large amount of Ru-MCOFs materials on the surface of the electrode, so that a stable electrochemical sensor is developed and assembled, and the stable electrochemical sensor can be used for detecting common foodborne pathogenic bacteria.

This invention belongs to the field of biosensing and fiber optic detection technology, and discloses a photoelectric-coupled fiber optic real-time in-situ detection system for monitoring the adsorption process of *E. coli* (DH5α). Addressing the core pain points of existing *E. coli* detection technologies, such as reliance on complex sample pretreatment (taking over 24 hours) and the inadequacy of false positives and sensitivity with single-fiber SPR or electrochemical detection, which fail to capture the dynamic process of bacterial adsorption, this invention uses a fiber optic SPR probe with a dual recognition layer consisting of a surface-modified dopamine polymer membrane, an LPS-specific nucleic acid aptamer, and a *E. coli* shape-imprinted cavity as the working electrode. It simultaneously acquires SPR resonance wavelength shift and electrochemical current signals, achieving cross-validation of multi-dimensional detection results. The system can be in-situ implanted into complex detection systems such as water samples and food homogenates without labeling. It exhibits strong anti-interference capabilities and high detection specificity, and can track the entire dynamic process of *E. coli* adsorption-desorption in real time. It can be widely applied in scenarios such as rapid on-site screening of foodborne pathogens, research on bacterial interfacial adsorption mechanisms, and monitoring of microbial pollution in aquatic environments.

The utility model discloses a swimming pool water escherichia coli detection device, and particularly relates to the technical field of water quality detection, the swimming pool water escherichia coli detection device is used for detecting escherichia coli in swimming pool water, and comprises a base and a top plate fixedly connected to the base, the base is provided with a test card carrying table used for placing an escherichia coli detection card, and a liquid guide pipe fixedly penetrates through the top plate; the top end of the liquid guide pipe is detachably connected with a sample liquid cylinder, the outer surface of the liquid guide pipe is fixedly communicated with a pipette, a liquid taking assembly is arranged in the liquid guide pipe, and the bottom end of the liquid guide pipe is provided with a lifting device for controlling the lifting of the liquid taking assembly; the number of the test card carrying tables is multiple, and the multiple test card carrying tables are arranged in a step shape. The bottom end of the sample liquid cylinder is fixedly connected with a threaded head, and the sample liquid cylinder is in threaded connection with the liquid guide pipe through the threaded head. The swimming pool water sample pipetting device solves the technical problems of complexity in pipetting and adding and insufficient pipetting content accuracy due to the fact that a swimming pool water sample is frequently sucked manually by means of a tool.

The invention relates to the technical field of biology, in particular to phage receptor binding protein D911 and application thereof. The invention provides preparation of an Escherichia coli phage receptor binding protein D911 and application of the Escherichia coli phage receptor binding protein D911 in detection of escherichia coli. The bacteriophage receptor binding protein D911 can specifically recognize and bind escherichia coli, the protein is further coupled with magnetic nanoparticles to form an escherichia coli receptor binding protein-magnetic bead conjugate D911-MNP, and a biological probe for specifically recognizing and binding escherichia coli is prepared and serves as an escherichia coli specific capture reagent. And a constructed escherichia coli separation and detection method. The method has the advantages of rapidness, convenience, specificity, sensitivity and accuracy, is expected to be applied to rapid detection of escherichia coli, and provides powerful technical support for escherichia coli detection in the fields of clinical diagnosis, food safety, environment and the like.

The invention belongs to the technical field of biological detection, and particularly discloses a method for rapidly and ultrasensitively detecting escherichia coli O157: H7 based on SERS (Surface Enhanced Raman Scattering). Comprising the following steps: preparing immunomagnetic bead capture nanoparticles, preparing precious metal or precious metal composite nanoparticle sol, preparing immune precious metal or precious metal composite signal nanoparticles, preparing a sandwich structure, and detecting escherichia coli O157: H7. According to the method, the antibody serves as a specific recognition element and is specifically combined with and used for measuring escherichia coli O157: H7, on one hand, the dispersed state of a nano material in a detection system can be stabilized, on the other hand, target protein can be recognized with high specificity and high affinity, and the method is good in stability, low in preparation cost and suitable for large-scale popularization and application. The detection accuracy is improved to a great extent; the method is higher in detection speed, extremely simple in detection process, short in time consumption, suitable for field rapid detection and batch screening, low in detection limit, ultra-high in detection speed and ultra-high in detection sensitivity, and capable of accurately recognizing trace target thalli.

The present application relates to the technical field of microbial detection automation equipment, and discloses a pretreatment equipment for escherichia coli detection, which solves the problems proposed in the background art, and comprises a base, a filling station and a rotary driving assembly arranged on the base. The driving assembly drives the L-shaped workbench to rotate between the initial station and the processing station through the sleeve. The sleeve is provided with a bag opening clamping mechanism on the side, and the elastic adaptive module is used to fix the bag opening, which can effectively buffer the tension when the bag opening is folded. The horizontal part of the L-shaped workbench is provided with a bag body processing mechanism, which comprises a sealing clamp driven by a bidirectional screw and provided with a sealing convex rib and a groove, and an inertia beating assembly driven by a cylinder and capable of reciprocating. The beating assembly realizes soft beating through the inertia of the flexible beating plate. The present application simulates the "holding bag" and "beating" actions of human hands through the automatic mechanism, realizes the automatic filling, sealing and efficient beating mixing of the homogeneous bag, and improves the automation degree and processing efficiency of the pretreatment.

The invention discloses preparation of an electrochemical sensor based on poly [2-(2, 6-naphthyl)-3, 4-bis (2-ethyl-hexyloxymethoxy) thiophene] and application of the electrochemical sensor in escherichia coli detection, and relates to the technical field of electrochemical biosensors. The novel electrochemical sensor is prepared by virtue of the synergistic effect of the conductive polymer and the nano material and is used for accurately detecting the escherichia coli (such as O157: H7) in food and water sources, the technology overcomes the defects that a traditional detection method is complicated in operation, long in time consumption, easy to pollute and the like, and high-sensitivity and high-selectivity detection on the escherichia coli in the food and water sources is realized.

The invention discloses an escherichia coli detection system based on a molecular crowding effect as well as a preparation method and application thereof, and belongs to the technical field of reagent detection. A molecular crowding agent is integrated into a test strip detection system, in the escherichia coli detection process, the molecular crowding agent and an aptamer probe (detection probe) marked by gold nanoparticles act together, a capture probe, the detection probe and target bacteria form a'detection probe-target bacteria-capture probe 'dual-aptamer sandwich compound on a detection line, and the detection probe and the capture probe can be used for detecting escherichia coli. According to the method disclosed by the invention, the specificity of the aptamer is not reduced, meanwhile, the binding affinity and the maximum binding capacity of the aptamer and escherichia coli are effectively improved, the enzyme resistance of the aptamer is improved, the gold nanoparticles are gathered, and a stronger developing signal is generated, so that the detection sensitivity of the test strip is improved.

The invention discloses a hot spot self-assembly colorimetric-Raman sensing platform and an escherichia coli detection method, the hot spot self-assembly colorimetric-Raman sensing platform comprises an isothermal amplification system, a CRISPR-dCas9 system, GNPs-probe and SA-GNPs, a target bacterial gene is taken as a DNA template, RPA amplification is carried out through the isothermal amplification system, and a double-chain amplification product modified by terminal biotin is obtained; the CRISPR-dCas9 system is used for targeted recognition of a double-chain amplification product modified by terminal biotin to form a composite product; gNPs-probe is composed of gold nanoparticles, a Raman signal molecule and a DNA probe, and the GNPs-probe is combined with the stem-loop structure of the sgRNA of the composite product through the DNA probe; sA-GNPs is combined with the biotin of the composite product through streptavidin; gNPs-probe and SA-GNPs are assembled on the composite product, so that a colorimetric-Raman sensing platform for detecting target bacteria is formed. According to the present invention, the cross validation of the generated colorimetric, ultraviolet and Raman multi-mode signals is adopted to improve the result reliability, the isothermal amplification and the self-assembly hot spot are adopted to enhance the multiple sensibilization detection signal, and the specificity is enhanced based on the specific primer group and the CRISPR-dCas9 system mediated secondary recognition, such that the rapid and accurate detection of the bacteria in the actual sample is finally achieved.

The invention relates to the technical field of visible light absorption spectrum detection, in particular to a three-dimensional fluorescence detection method and system for identifying escherichia coli in bile, and the method comprises the following steps: generating a light source through a light source generation module; adjusting the intensity of the light source by using a light splitting module, and dividing the light source into two paths of light so as to obtain sample detection light and a reference spectrum; acquiring a background spectrum and a bile detection spectrum by utilizing a sample detection module based on the sample detection light; according to the reference spectrum, the background spectrum and the bile detection spectrum, the upper computer uses a spectrum detection model to identify escherichia coli in the bile sample. Based on the detection principle of three-dimensional fluorescence, the intelligent degree and efficiency of detection of escherichia coli in bile can be improved, and the detection cost can be reduced.

The invention discloses a preparation method of a ratio type electrochemical luminescence biosensor, the sensor and application of the sensor in detection of escherichia coli O157: H7, and relates to the technical field of nano materials and biological detection. The sensor provided by the invention comprises an Aptamer-Templet double-strand body, a phi29 polymerase, a Nb.BbvCI nicking enzyme, a probe 1 and a probe 2, wherein the probe 1 and the probe 2 are connected with each other; the method comprises the following steps: specifically recognizing surface protein of escherichia coli O157: H7, releasing a Templet chain, releasing a Trigger chain and opening a hairpin structure of a probe 1 under the assistance of polymerase and cutting enzyme, and opening a hairpin structure of a probe 2 by the opened probe 1, so that self-assembly of the probe 1 and the probe 2 is realized, and a detectable object is obtained; the detection limit of the sensor to escherichia coli O157: H7 is as low as 1 CFU / mL, and the sensor is wide in linear range, high in stability, suitable for multiple samples, high in specificity and easy and convenient to use and operate.

The application discloses a microfluidic chip and a method for detecting water quality by embedding coliform group in alginate hydrogel, and the microfluidic chip comprises a sample inlet, an oil phase inlet, an alginate aqueous solution inlet, a droplet mixing flow channel, an incubation chamber and an outlet; wherein the oil phase inlet is connected with the sample flow channel through two oil phase flow channels which are divided into two parts and meet at a cross-shaped port, the alginate aqueous solution inlet is connected with the flow channel from the cross-shaped port through a water phase flow channel and meets at a T-shaped port; a contraction section flow channel and a first serpentine flow channel are sequentially arranged between the T-shaped port and the droplet mixing flow channel, and are respectively used for extruding and fusing the bacterial liquid droplet and the alginate droplet. The application solves the problem that the detection effect is poor due to the spontaneous fusion of droplets caused by the increase of incubation temperature in the prior art by combining the alginate with the calcium salt solution to form the hydrogel through ion cross-linking, and has a good application prospect in the detection of coliform group in water samples.

The application belongs to the technical field of biological detection, and particularly relates to a RPA primer for detecting Escherichia coli, a kit and application thereof. The target sequence is a new target DNA sequence which is broad-spectrum and specific in Escherichia coli. The RPA primer designed based on the target sequence can be used in recombinase polymerase isothermal amplification reaction of Escherichia coli. On this basis, the application provides a RPA detection method for detecting Escherichia coli by using the RPA primer. Compared with the existing PCR detection technology, the isothermal amplification detection method of the application can rapidly detect Escherichia coli at room temperature or under slight heating, and the detection can be completed within 30 min, thereby significantly improving the detection efficiency. Moreover, the detection method has high specificity, and the detection sensitivity can detect Escherichia coli as low as 10 1 copies / µL, and the specificity and sensitivity are much higher than those of the traditional PCR detection technology.

This invention relates to the field of biomedicine, specifically to an antibody for detecting Escherichia coli O45 and its application method. The antibody is a monoclonal antibody or its antigen-binding fragment, comprising the heavy chain CDR sequence shown in SEQ ID NO:1-3 and the light chain CDR sequence shown in SEQ ID NO:4-6. This invention also provides the nucleic acid molecule encoding the antibody, the expression vector, the host cell, and the preparation method thereof. Specificity identification results show that the antibody specifically binds to Escherichia coli O45 and shows no cross-reactivity with other Escherichia coli serotypes such as O157, O26, O103, O111, O121, and O145, as well as closely related serotypes of O55, and also shows no cross-reactivity with common foodborne pathogens. The indirect ELISA detection method based on this antibody has a detection limit of 1×10⁻⁶ for Escherichia coli O45. 2 The detection rate is CFU / mL, and the entire testing process can be completed within 24 hours. The monoclonal antibody provided by this invention can be used to prepare detection kits, test strips, and other products, and is suitable for rapid screening of O45 Escherichia coli in imported and exported food.

The methods for estimating the age of a human subject from her biological sample includes the step of obtaining biological samples from a multitude of individuals, such as blood plasma, saliva, or urine. The samples are biochemically processed, and DNA is isolated from them. The DNA is further prepared for sequencing and a sequencing library is created. The DNA samples are then sequenced using the NGS method. After sequencing, the genome of the individual's is obtained in the form of sequencing reads, which are subsequently mapped to a human reference genome. The mapped reads are statistically processed and a plurality of metrics such as number of DNA sequence substitution, insertion, deletion from short variations and structural variations categories, Escherichia Coli detection from Microbiome detection category, number of mutations from short variations and structural variations categories etc. are obtained. A machine learning model is trained and validated on a training set, and its accuracy is subsequently verified on a test set. When a new and unknown sample is available, it goes through the same biochemical and bioinformatic process. It is evaluated using a trained and validated model to estimate the age.

The invention relates to the technical field of microorganism detection automation equipment, and discloses pretreatment equipment for escherichia coli detection, which solves the problems in the background technology, and comprises a machine base, and a filling station and a rotary driving assembly arranged on the machine base. The driving assembly drives the L-shaped workbench to rotate between the initial station and the processing station through the sleeve. A bag opening clamping mechanism is arranged on the side of the sleeve, the bag opening is fixed through an elastic self-adaption module, and the pulling force generated when the bag opening is closed can be effectively buffered. A bag body processing mechanism is arranged on the horizontal portion of the L-shaped workbench and comprises a sealing clamp driven by a two-way lead screw and provided with a sealing convex rib and a groove, and an inertia flapping assembly driven by an air cylinder and capable of conducting reciprocating motion. The flapping assembly achieves soft flapping through the flexible flapping plate by means of inertia. According to the device, the bag lifting and flapping actions of human hands are simulated through the automatic mechanism, automatic filling, sealing and efficient flapping mixing of homogeneous bags are achieved, and the automation degree and the treatment efficiency of pretreatment are improved.