46results about How to "Low detection concentration" patented technology

The invention provides a primer and probe combination for multiple respiratory tract pathogen nucleic acid detection and typing identification of new coronaviruses based on multiple PCR time-of-flightmass spectrometry. The primer and probe combination comprises: 1) a primer sequence combination as shown in Table 1; and 2) a probe sequence combination as shown in a table 2. The invention also provides a kit for multiple respiratory tract pathogen nucleic acid detection and typing identification of new coronaviruses based on multiple PCR time-of-flight mass spectrometry. According to the invention, based on a MassARRAY MALDI-TOF MS system, multiple respiratory tract pathogens can be detected at the same time, and typing identification can also be carried out on the 2019 novel coronavirus (2019nCoV), so that the kit has more significance in clinical and virus research.

The invention discloses a kit for detecting pig epidemic diarrhea viruses, pig transmissible gastroenteritis viruses and pig rotaviruses. The kit comprises primer pairs shown by SEQ ID NO:1-2, SEQ ID NO:3-4 and SEQ ID NO:5-6 for respectively performing specific amplification on the pig epidemic diarrhea viruses, the pig transmissible gastroenteritis viruses and the pig rotaviruses. The invention also discloses applications of the primer pairs shown by the SEQ ID NO:1-2, the SEQ ID NO:3-4 and the SEQ ID NO:5-6 in preparation of reagents for detecting the pig epidemic diarrhea viruses, the pig transmissible gastroenteritis viruses and the pig rotaviruses. The detection kit disclosed by the invention can be used for accurately and effectively detecting the pig epidemic diarrhea viruses, the pig transmissible gastroenteritis viruses and the pig rotaviruses, and is strong in specificity, high in sensitivity, short in time consumption, rapid in detection and good in application prospect.

The invention adopts oligonucleotide aptamers for identifying special tripeptide sequence KAI, GEL, DGI and LAS, extanding oligonucleotide aptamers by Structure-switch and phosphorylation decorating 5' end thereof, synthetising four connexons; connecting oligonucleotide aptamers combinated with target albumen through proximity dependent DNA Ligation technique as chain ringlike DNA; amplifying detecting signals via rolling-circle DNA duplicate method; the technique can detect target albumen sensitively, the least detecting concentration can get nM level; this method with flexibility can adjust according needed numbers of ligand; can detect albumen composite, provide sensitive detecting method for chip technique using oligonucleotide aptamers as ligand.

The invention relates to an application method of a ratio-type cyanide ion fluorescent probe molecule. The invention belongs to the technical field of anion detection. The method is characterized in that the method is an application of a ratio fluorescent probe molecule, which is 1,2,2,3-tetramethyl-4,5-benzoindoline, used in cyanide ion detection. The probe molecule is obtained by a one-step process of periodic methane alkylation of 2,3,3-trimethyl-4,5-benzindole. In a system where DMF:H2O=1:1 (V / V), the probe molecule is excited by using 320nm light, and emission occurs at 461nm. When cyanide ion is added, intra-molecular charge transfer (ICT) process is broken, emission peak at 461nm is reduced, and new emission peak occurs at 425nm. Therefore, solution fluorescence is turned from bluish green to deep blue. In a system wherein cyanide ion coexists with other anions, the probe molecule shows high interference resistance, high specificity, and high sensitivity.

The invention discloses an acetone air sensitive material and the application of the same, relating to an air sensitive material for detecting acetone steam and the application of the same. The invention solves the problems that the prior acetone air sensitive material can not response to acetone gas selectively due to the existence of ethanol and normal propyl alcohol, and has high minimal detection limit to the acetone. The general expression of the acetone air sensitive material of the invention is A1-xA' xB1-yB' yO3, wherein, A is La or Nd; A' is Sr, Sm, Ce or Pb; B is Cr, Ni, Fe or Co; B' is Ti, Mn, Mg or Cu; x is more than or equal to 0 and less than or equal to 1, y is more than or equal to 0 and less than or equal to 1, x and y are not simultaneously 0 or 1, and when one of x and y is 0, the other is not 1. The acetone air sensitive material of the invention is used as thick-film sensitive element; according to the ratio of the portion by weight, the thick film of the thick-film sensitive element is made by 84 to 92 portions of acetone air sensitive materials, 4 to 8 portions of glass powder and 4 to 8 portions of terpilenol. The acetone air sensitive material of the invention decreases the detecting viscosity of the acetone gas, is not interfered by the wetness of the environment, and is of good selectivity for the acetone gas.

The invention discloses a two-photon fluorescent probe as well as a preparation method and application thereof. The two-photon fluorescent probe takes coumarin and rhodamine as a matrix. The structure of the two-photon fluorescent probe is described in the specification. Molecules of the two-photon fluorescent probe show relatively high selectivity and sensitivity in a system in which palladium ions (II) and other positive ions coexist. A cytotoxicity test shows that the two-photon fluorescent probe disclosed by the invention has hardly any toxic effect on cells, and a two-photon fluorescence microscopy imaging experiment shows that the two-photon fluorescent probe has good HeLa cell permeability and is applicable to detection of distribution of palladium ions (II) in cells.

The invention discloses a two-photon fluorescent probe as well as a preparation method and application thereof. The two-photon fluorescent probe takes carbazole as matrix. The structure of the two-photon fluorescent probe is described in the specification. Molecules of the two-photon fluorescent probe show specificity response and high sensitivity in a system that trivalent gold ions (Au<3+>) and other interference reagents coexist. Cytotoxicity tests show that the probe almost has no toxic or side effect on cells, and two-photon confocal fluorescence microscopic imaging tests show that the probe has good HeLa cell permeability and is applicable to two-photon fluorescence imaging and qualitative detection on Au<3+> in a cell mitochondrion.

The invention discloses a cavity structure array assembled by silver nanoparticles as well as a preparation method and application of the cavity structure array. The structure is composed of a conductive substrate and a silver nanostructure on the conductive substrate, the silver nanostructure is a porous film formed by stacking silver nanoparticles, and holes are of spherical cavity structures arranged in order; and the preparation method comprises the following steps that silver nitrate powder, citric acid powder, ethylenediaminetetraacetic acid powder, sodium sulfite powder and dipotassiumphosphate powder are dissolved in water to obtain an electrolyte, and then the conductive substrate sputtered with the gold film with the thickness of 15-30 nm and covered with one or more layers of polystyrene microsphere crystal templates in sequence serves as a cathode, a graphite flake serves as an anode to be placed in an electrolyte for electro-deposition, and a target product is prepared onthe conductive substrate. The prepared cavity structure array assembled by the silver nanoparticles has three-dimensionally distributed SERS hot spots, the SERS sensitivity is high, rhodamine 6G withthe concentration as low as 1 fmol / L can be detected, and the cavity structure array can be easily and widely commercialized to serve as an active substrate for surface-enhanced Raman scattering.

The invention adopts oligonucleotide aptamers for identifying special tripeptide sequence KAI, GEL, DGI and LAS, extanding oligonucleotide aptamers by Structure-switch and phosphorylation decorating 5' end thereof, synthetising four connexons; connecting oligonucleotide aptamers combinated with target albumen through proximity dependent DNA Ligation technique as chain ringlike DNA; amplifying detecting signals via rolling-circle DNA duplicate method; the technique can detect target albumen sensitively, the least detecting concentration can get nM level; this method with flexibility can adjust according needed numbers of ligand; can detect albumen composite, provide sensitive detecting method for chip technique using oligonucleotide aptamers as ligand.

This invention is a manufacturing method of the sensitive material, formaldehyde sense organ made by sensitive material and the sense organ. It relates to a sensitive material that can detect formaldehyde, sense organ that can measure the viscosity of formaldehyde and the manufacturing method. This invention settles the problem of long-time response and recovery, high working temperature of the current sense organ to detect formaldehyde. The general formula of the sensitive material is B2-aAbO3, A is Sn,Pb,Ti or Zr, B is Mo, W,Cr or Mn, 0 G01N 35 / 00 G01N 27 / 00 3 7 2 2007 / 3 / 14 101021544 2007 / 8 / 22 000000000 Heilongjiang Univ. Harbin 150080 Huo Lihua P. Suman Zhao Hui Gao Shan Cheng Xiaoli hanmo zhu 23109 The Patent Agency of Songhuajiang Prefecture of Heilongjiang Province No.6 Hexing Street, Dongli District, Harbin, Heilongjiang Province 150040

The invention provides a double droplet type digital PCR absolute quantification kit for AIV H7N9 subtypes. The double droplet type digital PCR absolute quantification kit comprises two pairs of specific primer pairs and two specific probes used in cooperation with specific primers, and nucleotide sequences are as shown in SEQ ID No.1-6 respectively. According to the double droplet type digital PCR absolute quantification kit, AIV H7N9 subtypes can be detected quickly, specifically and sensitively through a digital PCR instrument, and the detection sensitivity reaches one copy. The double droplet type digital PCR absolute quantification kit is simple in use method, low in cost, capable of detecting the AIV H7N9 subtypes quickly, directly and quantitively without a standard curve, very applicable to disease supervision, on-site emergency detection and clinical sample detection, and suitable for application and popularization in a wide range.

The invention provides a method for detecting antibiotics in drinking water to solve the problem that the existing fluorescent detecting article cannot achieve detection of a plurality of targets. Themethod includes the first step of preparing an H3dcpcpt rare earth complex; the second step of preparing an H3dcpcpt rare earth complex solution; the third step of conducting H3dcpcpt rare earth complex fluorescence detection; the fourth step of conducting drinking water fluorescence detection; the fifth step of calculating. The method is used for detecting the antibiotics in the drinking water.

The invention relates to a method used for detecting manganese ions in drinking water. The method is used for solving a technical problem that detection concentration of fluorescence detection via quenching or strengthening is high. The method comprises following steps: 1, a dibenzoyltartaric acid rare earth complex is dissolved in a N,N'-dimethylformamide solution so as to obtain a mixed solution; 2, drinking water and the mixed solution are mixed at a volume ratio of 1:1, ultraviolet irradiation is adopted, and the color of an obtained mixed solution product is observed, wherein, when the concentration of manganese ions in drinking water is higher than 0.05ppm, the color of the mixed solution product is changed from white to blue. The method is simple; detection concentration is low; white light materials are used for detecting manganese ions in drinking water, when the concentration of manganese ions is equal to or higher than 0.05ppm, the color of the white materials is changed into blue; detection limit accords with world health organization standards. The invention belongs to the technical field of detecting of manganese ions in drinking water.

The invention discloses an electrochemical sensor for simultaneously detecting PAT and OTA, a preparation method and a detection method. The electrochemical sensor comprises a working electrode, a reference electrode and a counter electrode, and the surface of the working electrode is sequentially coated with an AuNPs-BP nano composite material layer and an identification sensitive layer for identifying an object to be detected; the AuNPs-BP nano composite material layer is coated on the surface of the working electrode, and the identification sensitive layer is coated on the surface of the AuNPs-BP nano composite material layer; the identification sensitive layer comprises a PAT aptamer chain, a PAT complementary chain, an OTA aptamer chain and an OTA complementary chain. The electrochemical sensor can detect PAT and OTA at the same time, detection of two target objects is achieved through the same electrochemical sensing platform, and the detection concentration is low.

The invention relates to a method for detecting silver ions in drinking water, and aims to solve the technical problem that low detecting concentration is difficult to be reached as fluorescence detection is performed by the aid of a quenching or enhancing method. The detecting method includes the steps: firstly, dissolving bibenzoyl tartaric acid coordination compounds into N, N'-dimethyl formamide solvents to prepare into mixed liquid; secondly, mixing the drinking water and the mixed liquid according to the volume ratio of 1:1, irradiating mixture by the aid of ultraviolet light by the aid of the wave length ranging from 320nm to 324nm, observing a solution color. The solution color changes into red from white when the concentration of the silver ions in the drinking water is higher than 0.05ppm. The method is simple to prepare, low in detecting concentration, the silver ions in the drinking water are detected by the aid of white-light materials, the color of the white-light materials changes into red when the concentration of the silver ions is equal to or higher than 0.05ppm, and detection limit meets world health organization standards.

The invention provides a method and kit for detecting Helicobacter pylori drug resistance gene mutations. Specifically, the method detects drug resistance gene site mutations of five commonly used Helicobacter pylori antibiotics (including clarithromycin, metronidazole, quinolones, amoxicillin and tetracycline) based on multiplex PCR-Time-of-flight mass spectrometry, and matching primer and probecombinations and the kit are provided.

The invention provides a method for detecting furfural content of transformer oil. The method is characterized by comprising steps as follows: step 1, furfural dissolved in the transformer oil is extracted; step 2, furfural extract is subjected to Raman spectrum detection; step 3, furfural is quantified according to a Ramancharacteristic peak value of furfural. In the step 1, furfural dissolved the transformer oil is extracted with deionized water; in step 2, a Raman peak at 1372 cm<-1> or 1411 cm<-1> is taken as a Ramancharacteristic peak of furfural, furfural concentration is taken as a horizontal coordinate x, the Ramancharacteristic peak value of furfural is taken as a vertical coordinate y, and the furfural content of the transformer oil is determined according to the furfural quantitative analysis model as follows: y=-303.35323+39.90799x. According to the method, the deionized water is used as an extraction agent, Raman intensity of trace furfural dissolved in the transformer oilis greatly enhanced, Raman detection sensitivity of the of trace furfural dissolved in the transformer oil is greatly improved, and online monitoring level for transformer insulating condition is improved.

The invention provides an application of an AlGaAs / GaAs HEMT biosensor in detection of an IL-1beta potential inhibitor, and the application is characterized in that the IL-1beta-AlGaAs / GaAs HEMT biosensor is constructed by using an AlGaAs / GaAs HEMT device as a transducer and using interleukin 1beta protein modified on the HEMT device as an identification element through self-assembly of a single layer, the IL-1beta-AlGaAs / GaAs HEMT biosensor is used for identifying the IL-1beta potential inhibitor, and the IL-1beta-AlGaAs / GaAs HEMT biosensor is used for detecting the IL-1beta potential inhibitor. The detection concentration is as low as pM level, the detection range covers five orders of magnitude, and the method has high sensitivity and strong specificity.

The invention discloses a kit for detecting the existence and content of an insecticide in a water body. The kit comprises the following components: XB1 protein, fast blue B salt, beta-naphthyl acetate and 50mM phosphate buffer with the pH of 7.0. The XB1 protein is protein (a) or protein (b), wherein the protein (a) is shown by a sequence 1 in a sequence table, and the protein (b) is shown by amino acid residues from a position-39 to a position-574 at the N terminal of the sequence 1 in the sequence table. Experiments prove that the XB1 protein from spodoptera litura has carboxylesterase activity and can react with the beta-naphthyl acetate serving as a natural substrate to form beta-naphthol, the fast blue B salt performs color development, and red is obtained; and carboxylesterase can completely or partially lose enzymatic reaction capacity to decrease the red after being inhibited by organic phosphorus, carbamates or pyrethroid insecticides, and the decrease degree of the red is in direct proportion to the type and concentration of the insecticide. The kit can quickly detect the insecticide in the water body.

The invention discloses a preparation method of a flexible SERS (Surface Enhanced Raman Scattering) substrate, and relates to the technical field of surface enhanced Raman scattering. The preparationmethod comprises steps of (1) primarily oxidizing a carbon cloth; (2) deeply oxidizing the carbon cloth: adding hydrogen peroxide into the reaction system in the step (1) until no bubbles are generated in the reaction system, and cooling to room temperature; and (3) taking out the carbon oxide cloth, cleaning and drying to obtain the flexible SERS substrate. The invention also provides the flexible SERS substrate prepared by the preparation method and application of the flexible SERS substrate in trace detection of organic matters. The preparation method has the beneficial effects that noble metal nanoparticles do not need to be loaded on the carbon cloth, and the commercial carbon cloth is oxidized by adopting a simple oxidation method, so that rich oxygen-containing functional groups aregenerated on the surface of the commercial carbon cloth. By utilizing the charge transfer property between the surface functional group and the organic matter and the foldability of the carbon cloth,the SERS substrate which is flexible and convenient to use is formed.

The invention discloses a two-photon fluorescent probe as well as a preparation method and an application thereof. The structure of the two-photon fluorescent probe is shown in the specification. The two-photon fluorescent probe presents relatively high selectivity and high sensitivity in a coexisting system of aminothiopropionic acid or homocysteine and other amino acids. The cytotoxicity test shows that the two-photon fluorescent probe almost has no toxicity on cells. The two-photon fluorescent microscopic imaging experiment shows that the two-photon fluorescent probe is good in permeability on 293FT cells. The two-photon fluorescent probe is suitable for detecting the distribution of amino acid micromolecules in the cells.

The invention discloses a kit for detecting pig epidemic diarrhea viruses, pig transmissible gastroenteritis viruses and pig rotaviruses. The kit comprises primer pairs shown by SEQ ID NO:1-2, SEQ ID NO:3-4 and SEQ ID NO:5-6 for respectively performing specific amplification on the pig epidemic diarrhea viruses, the pig transmissible gastroenteritis viruses and the pig rotaviruses. The invention also discloses applications of the primer pairs shown by the SEQ ID NO:1-2, the SEQ ID NO:3-4 and the SEQ ID NO:5-6 in preparation of reagents for detecting the pig epidemic diarrhea viruses, the pig transmissible gastroenteritis viruses and the pig rotaviruses. The detection kit disclosed by the invention can be used for accurately and effectively detecting the pig epidemic diarrhea viruses, the pig transmissible gastroenteritis viruses and the pig rotaviruses, and is strong in specificity, high in sensitivity, short in time consumption, rapid in detection and good in application prospect.

This invention is a manufacturing method of the sensitive material, formaldehyde sense organ made by sensitive material and the sense organ. It relates to a sensitive material that can detect formaldehyde, sense organ that can measure the viscosity of formaldehyde and the manufacturing method. This invention settles the problem of long-time response and recovery, high working temperature of the current sense organ to detect formaldehyde. The general formula of the sensitive material is B2-aAbO3, A is Sn,Pb,Ti or Zr, B is Mo, W,Cr or Mn, 0<a=b<1. The sense organ consists of explosion-prevention net, two heating probes, four detecting probes, thick-film sense organ, probe basis, connecting work and heating device. This invention has such merits as low detecting viscosity of formaldehyde, low working temperature, short response time and high stability of the sense organ.

The invention provides a staphylococcus aureus detection kit and a manufacturing method thereof, and belongs to the field of kits. The kit is coated with an immunomagnetic bead probe of gold nanoparticles, a gold nanoparticle probe, an etching solution and a standard bacteria solution. The immunomagnetic bead probe coated with the gold nanoparticles is prepared by the following steps: preparing magnetic beads coated with the gold nanoparticles; and coupling the magnetic beads with staphylococcus aureus specific chicken egg yolk antibody IgY. The gold nanoparticle probe is obtained by firstly synthesizing gold nanoparticles and coupling the gold nanoparticles with a staphylococcus aureus specific aptamer. The kit manufactured in the invention has advantages of strong specificity, high sensitivity and short detection time during staphylococcus aureus detection, a minimum detection concentration is as low as 10cfu / mL, and the kit can be used for detecting the staphylococcus aureus in food.

The invention discloses a method of determining anti-thrombin activity of hirudin. The method includes: allowing hirudin having certain mass and containing unknown activity to react with sufficient thrombin, allowing cross-linking reaction under the action of cross-linking agent BS3 to obtain a first mixture system containing the hirudin, the thrombin and a hirudin-thrombin compound after completion of cross-linking, performing optical density scanning after electrophoresis, acquiring mass of the hirudin-thrombin compound according to protein band density of the hirudin-thrombin compound on the basis of a control having known protein band density, combining the hirudin and the thrombin according to a mass ratio: 1:5 so as to obtain the hirudin-thrombin compound so as to acquire mass of effective thrombin participating in reaction, and performing calculating according to the mass fraction of the effective thrombin in the thrombin and the mass of the hirudin so as to obtain an activity value of the hirudin, having the certain mass, in inhibiting the thrombin, namely an anti-thrombin activity value of the hirudin. The method is simple to operate, good in accuracy and low in investment and has low equipment requirements.

The invention discloses a switch-type ferric ion fluorescence probe and a preparation method thereof. Rhodamine B is adopted as a matrix of the switch-type ferric ion fluorescence probe, and the structural formula of the switch-type ferric ion fluorescence probe is as follows (refer to the Specification). According to the invention, fluorescence probe molecules demonstrate higher selectivity and sensitivity in the concomitant system of ferric ions and other positive ions; a fluorescence development experiment shows that the fluorescence probe molecules have excellent cell penetrability, are nontoxic for cells, and can be used for detecting the concentration and distribution of ferric ions in cells.

The invention discloses a cavity structure array assembled by silver nano particles and a preparation method and application thereof. The structure is composed of a conductive substrate and a silver nanostructure on it, wherein the silver nanostructure is a porous film stacked with silver nanoparticles, and the holes are a spherical cavity structure arranged in an orderly manner; the preparation method is to firstly combine silver nitrate powder, lemon Acid powder, ethylenediaminetetraacetic acid powder, sodium sulfite powder and dipotassium hydrogen phosphate powder are dissolved in water to obtain an electrolyte solution; then a 15-30nm thick gold film is sequentially sputtered and covered with one or more layers of polystyrene microsphere crystals The conductive substrate of the template is used as the cathode, and the graphite sheet is used as the anode to be electrodeposited in the electrolyte, and the target product is prepared on the conductive substrate. The prepared silver nanoparticle-assembled cavity structure array has three-dimensionally distributed SERS hot spots, high SERS sensitivity, capable of detecting Rhodamine 6G at concentrations as low as 1 fmol / L, and is extremely easy to be widely commercialized as a surface-enhanced Raman scattering activity. base.

The invention provides a high-sensitivity nitrite ion electrode based on poly(3,4-ethylenedioxythiophene). The high-sensitivity nitrite ion electrode sequentially comprises a metal wire, a conductive poly(3,4-ethylenedioxythiophene) film, a nitrite ion sensitive film and a glass tube from inside to outside. The nitrite ion sensitive film comprises a 3,4-ethylenedioxythiophene film - styrene sulfonic acid copolymer. The 3,4-ethylenedioxythiophene film - styrene sulfonic acid copolymer is adopted to serve as a film-forming material of the sensitive film and replace PVC in the prior art, has good compatibility with conductive poly(3,4-ethylenedioxythiophene) of an adjacent layer, improves interlayer acting force and reduces interlayer signal transmission loss, so that the sensitivity of the ion electrode is further enhanced, and the lower limit of the electrode detection concentration is as low as 108 mol / L. Adsorption points of the copolymer are increased, the ion adsorption capability of the copolymer is improved, and the detection range of nitrite ions is expanded.