58results about How to "Rule out false positives" patented technology

The invention discloses a method for detecting pesticide residues in sulfur-containing vegetables by an enzyme inhibition method. The method comprises the following steps of 1, preparing a standard solution, 2, preparing a sample, 3, testing control groups through the processes of adding a buffer solution into a beaker, adding dropwisely acetate or sodium hydroxide into the beaker, adjusting a pH value of the mixed solution to a pH value of 9, adding an enzyme solution and a color-developing agent into the mixed solution with a pH value of 9, shaking up, standing at a temperature of 37 DEG C for 15 minutes, adding a substrate solution into the mixed solution treated by the previous step, shaking up, and detecting an absorbance variation value delta A0 of the mixed solution undergoing a reaction at wavelength of 410 nanometers for 3 minutes by a spectrometer, 4, adding sulfur-containing vegetable sample extract into a beaker, carrying out processes same as the processes of the step 3, and detecting an absorbance variation value delta A1 of a vegetable sample mixed solution undergoing a reaction at wavelength of 410 nanometers for 3 minutes by a spectrometer, and 5, calculating an enzyme inhibition percentage according to a formula of an enzyme inhibition percentage=[(delta A0-delta A1)/delta A0]*100, wherein when the calculated enzyme inhibition percentage is great than or equal to 50%, it is shown that there are pesticide residues in the detected sulfur-containing vegetable. The method eliminates the interference of sulfides in a sulfur-containing vegetable on pesticide residue detection through adjustment of a pH value of a vegetable sample solution, can rapidly, simply and accurately detect a pesticide residue ratio of a sulfur-containing vegetable, has a low cost, and is suitable for on-site detection.

A 3D grid detection technique for detecting object nuclein and object protein includes requiring to add hybridized protein or hybridized probe on one of grid component when object nuclein or object protein is detected then coordinating by immobilized catch-protein or catch-probe to realize specificity-catch of object nuclein or object protein.

The invention discloses a method for rapidly screening and certifying veterinary drug residue in milk. The method comprises the following steps: extracting a sample by 5% of formic acid acetonitrile,purifying by a QuEChERS EMR-Lipid technology, and screening and certifying by LC-QTOF. A first-level screening spectrum library of 134 drugs is built, and the methodology validation is performed to 40common veterinary drugs. The method has the good sensitivity, accuracy and repeatability. The first-level spectrum library scanning is performed to the practical sample, the discovered veterinary drug residue is further certified through the second-level mass spectrum analysis, and finally a standard substance is used for verification. The method is capable of discovering the problems which are hardly discovered in the daily detection, and satisfying the requirements of evaluating and supervising the drug residue in the milk.

The invention discloses a sample diluent for immunofluorescence chromatography detection. The problem that the detection sensitivity and accuracy cannot be more effectively increased when the current pretreatment reagent is only used for preventing the matter from non-specifically adsorbing on an immunochromatography test strip is solved. The sample diluent comprises a buffering matter, a sealing agent, a hydrophilia macromolecule matter, a surface active agent, a metal-chelator, a corrosion remover and sodium chloride. The sample diluent provided by the invention can be used for more effectively increasing the detection sensitivity and accuracy and has an obvious effect.

The invention belongs to urine detection reagents and particularly relates to a reagent for detecting an abnormal metabolite, namely tryptophan, in a human body and a preparation method of the reagent. The reagent for detecting a tumor marker, namely tryptophan, in urine comprises aqueous solutions of Hg<2+>, Hg2<2+>, Ni<2+>, WO4<2->, SO4<2->, NO3<-> and SeO3<2->. The preparation method comprises the following steps: preparing a sulfuric acid solution; preparing a nitric acid solution; preparing a solution A; preparing a solution B; preparing a solution C; preparing a solution D; preparing a solution E; mixing. According to the technical scheme provided by the invention, raw materials are easily obtained and are cheap, the preparation process is simple, the obtained reagent is stable in performance and has the characteristics of strong universality, high sensitivity, good specificity and the like when the reagent is applied to cancer detection, and the detection is simple in process, short in time and easy in judgment, so that the reagent is particularly applicable to the massive population check and the treatment effect check of cancer patients.

This invention relates to a method for identifying 28 kinds of common pathogens of clinical bacteremias, which crosslinks 30 types of specific probes against the 28 kinds of common pathogens on 30 kinds of different fluorescent microspheres to be reacted with the being tested specimens then to be reacted with the report molecules labeled by fluorescent elements to test the specific 23SrDNA of them on a fluorescent test device.

The invention relates to a detection kit for isothermal amplification of nucleic acid for the white spot syndrome virus and a detecting method thereof. The kit is designed by using a set of LAMP primers as the main body designed according to the gene conserved sequence of the white spot syndrome virus. The kit is provided with eleven agents needed by WSSV detection including SEMP lapping liquid, nucleic acid extract, UNG enzyme, TE buffer solution, enzymolysis buffer solution, LAMP reaction solution and on the like, thus realizing a programmed and standardized detection; therefore, the invention has the advantages of the highest sensitivity, simplicity, rapidity, safety, good specificity and low cost, and the amount of the copies detected with virus can be as low as 26. Only one water-bath is needed to correctly detect the white spot syndrome virus in prawns and aquaculture water within 2 hours by the kit and the detecting method. Moreover, the problem that the detection is subject to interference in the LAMP technology is also solved. The detecting method of the invention is expected to substitute the previous related detecting methods of the white spot syndrome virus, such as the electron microscope method, the TE staining method, the biopsy method, the antibody detecting method, the nucleic acid probe hybridization method and the PCR detecting method.

Aiming at the condition that an existing mammary gland focus detection algorithm can only carry out focus detection on a single image and cannot give out the corresponding relation of focuses on two visual angles of the same breast, the invention provides a mammary gland focus matching method comprising multiple links, a matching relation is given out for the focuses detected from different visualangles on the same breast, the types and attributes of the lesions can be judged more accurately, and part of false positive lesions can be eliminated to a certain extent.

The invention relates to a method for detecting 9 kinds of mycotoxins in a cassia seed medicinal material. The method comprises the following steps: a step 1: preparation of a standard substance stocksolution; a step 2: preparation of a mixed standard substance stock solution; a step 3: preparation of a standard working solution; a step 4: preparation of a tested object solution; a step 5: preparation of a substrate matching standard solution; a step 6: determination.

The invention discloses a method for detecting chloramphenicol residual in a functional food through HPLC-MS-MS. The method comprises the following steps: weighing a sample, adding deuterated chloramphenicol as an internal standard solution, adding ethyl acetate, ammonium hydroxide and anhydrous sodium sulfate, homogeneously extracting, centrifuging, and transferring the obtained supernatant to a heart-shaped bottle; concentrating the supernatant in the heart-shaped bottle to dryness; dissolving with water, carrying out ultrasonic treatment, adding n-hexane, carrying out vortex mixing, allowing the obtained solution to stand for layering, discarding n-hexane which is the upper layer, adding n-hexane, carrying out vortex mixing, allowing the obtained solution to stand for layering, transferring the obtained water phase to a centrifuge tube, centrifuging, and allowing the centrifuged water phase to go through a filter membrane to obtain a final solution for the determination through HPLC-MS-MS; accurately weighing a chloramphenicol standard substance, carrying out ultrasonic dissolving with chromatographically pure methanol, adding the chromatographically pure methanol to a constant volume, and preparing chloramphenicol standard substance solutions having different concentrations; determining the chloramphenicol standard substance solutions through the HPLC-MS-MS to obtain a standard curve; and calculating according to obtained examination data through the standard curve to obtain the concentration of chloramphenicol in the sample to be measured. The method has the advantages of good accuracy, high precision and good linearity.

The invention provides a multiplex suspension chip for the detection of cryptosporidium species and Giardia lambila Stiles. The chip comprises diagnosis primer and specific oligonucleotide probes coupled with microspheres, wherein the sequence of the oligonucleotide probes is a sequence in specific genes of cryptosporidium species or genus specific or giardia lamblia species. The chip is combined with a multiplex PCR technique and a liquid-phase hybridization technique, can effectively eliminate false positivity, guarantees accurate specificity, improves sensibility by 10 to 1,000 times than common PCR technique, can simultaneously identify and detect two types of aquagenic protozoa, such as cryptosporidium species, C.parvum, Giardia lambila Stiles and the like, and has the characteristics of high specificity, high sensibility, speediness, low cost, popularization easiness and the like.

The invention belongs to the field of biological immunochromatography detection methods and specifically relates to a nano selenium kit for quickly detecting HE4 and CA125 and a preparation method thereof. The kit is composed of a sample pad, a combined pad, a reaction pad, a water absorption pad and a PVC bottom plate, wherein a detection line T1 coated by an anti-CA125 antibody A2, a detection line T2 coated by an anti-HE4 antibody B2 and a quality control line C coated by goat anti-rat IgG are arranged on the reaction pad; by means of observing color development reaction of the detection lines, bedside quick screening diagnosis of early ovarian cancer can be achieved. The prepared nano selenium immunochromatography kit disclosed by the invention has the advantages of strong specificity,high sensitivity, good accuracy, convenience, quickness, small sample amount to be detected and suitability for screening, homelab and bedside quick detection of high-risk groups for ovarian cancer.

The invention belongs to the technology of in-vitro diagnosis, and discloses a method for eliminating HRP (Horseradish Peroxidase) antibody interference. A blocking agent is added into an immunodetection system taking horseradish peroxidase as a marker, and the blocking agent is inactivated HRP with a prosthetic group being removed. The combination of the inactivated HRP with the prosthetic groupbeing removed and the HRP antibody can block the combination of the HRP antibody and an HRP labeled antibody or an HRP labeled antigen in the serum, so that the interference of the HRP antibody on thedetection result is eliminated. According to the method for eliminating HRP antibody interference, the common problem existing in the immunodetection system taking horseradish peroxidase as a markeris solved, false positive caused by HRP antibody interference is eliminated, especially multi-item IgM false positive occurring during IgM joint detection is eliminated, and the problem of poor magnitude correlation caused by HRP antibody interference in immunoassay can also be improved. The addition of the blocking agent does not influence the detection result of a normal sample and improves theaccuracy of the detection result.

The invention discloses lateral flow immunochromatographic assay test paper based on a gold magnetic nano-enzyme immune probe, as well as a preparation method and an application of the lateral flow immunochromatographic assay test paper, and belongs to the technical field of biological analysis. The preparation method comprises the following steps of: preparing Fe3O4/Au composite nanoparticles byadopting an in-situ reduction method, then preparing the gold magnetic nano-enzyme immune probe by adopting a physical or chemical method, and finally finishing membrane material treatment and assembly of lateral flow immunochromatographic test paper to obtain the lateral flow immunochromatographic assay test paper based on the gold magnetic nano-enzyme immune probe. In the preparation method, more enzyme catalytic active sites are provided by utilizing a Fe3O4/Au composite nanoparticle phase, an enzyme catalytic chromogenic reaction rate is effectively improved, and the preparation method hasthe advantages of simple process, low cost and easiness in large-scale production; and compared with the existing lateral flow immunochromatographic test paper, the lateral flow immunochromatographicassay test paper based on the gold magnetic nano-enzyme immune probe has the advantages that the detection sensitivity can be improved by 2-3 orders of magnitudes, the specificity of a detection system is high, and an efficient detection technology is provided for marker analysis with low detection limit.

The invention discloses a group A streptococcus antigen detection test strip and kit and preparation methods thereof, and relates to the technical field of group A streptococcus detection. The group Astreptococcus antigen test strip is prepared by sequentially attaching a nitrocellulose membrane coated with an anti-group A streptococcus detection antibody, an immune binding pad coated with an anti-group A streptococcus immunolabeled antibody, absorbent paper and a sample pad to a polyvinyl chloride bottom plate; a detection card can detect whether a group A streptococcus antigen is present ina sample to be detected or not by detecting a marker; and the test strip and the detection card comprising the test strip can specifically and quickly detect and diagnose early infection of group A streptococcus, thereby reducing the cost, realizing rapid detection and meeting the requirements of clinical use.

The invention discloses a nucleic acid multiplex isothermal amplification detection kit for detecting WSSV and IHHNV of a prawn simultaneously, which comprises a grinding liquid tube filled with a grinding liquid, a nucleic acid extraction liquid tube A filled with the solution of sodium acetate, a nucleic acid extraction liquid tube B filled with absolute ethanol, a nucleic acid extraction liquid tube C filled with ethanol of which the mass concentration is 70 percent, a buffer solution E filled with TE buffer solution, a UNG enzyme tube filled with uracil-DNA glycosylase, a multi-LAMP reaction liquid tube filled with a multi-LAMP reaction liquid, a Bst DNA polymerase tube filled with Bst DNA polymerase, a color developing agent tube filled with a nucleic acid dye SYBR Green I, and positive control nucleic acid tube filled with positive DNA of the WWS and the IHHNV, of the prawn, in a copy number ratio of 1 to 1, and a negative control tube filled with sterilized double stilled water. The invention also provides a method detecting the WSSV and the IHHNV of the prawn simultaneously, which has high detection sensitivity.

The invention relates to a detection reagent and a kit for detecting male-sterility. Concretely, the detection reagent comprises 1) at least one of a GLP DAZ a probe set and a GLP DAZ b probe set, and 2) a CSP 18 probe set. The kit comprises the detection reagent dissolved in a TE Buffer, wherein each one of the probe sets in the kit has concentration of 50 to 300 ng/microliter. The invention also relates to a use of the detection reagent and the kit in detection of DAZ gene family deletion, and a method for detection of DAZ gene family deletion.

The invention belongs to the technical field of microbiological detection, in particular relates to a primer and a probe for specific detection on enterobacter sakazakii and applications of the primer and the probe, and further discloses a method for specific detection on enterobacter sakazakii. The primer for specific detection on enterobacter sakazakii has the following sequential structure: enterobacter sakazakii-F: 5'-AGG GGA TAT TGT CCCC TG AAA CAG-3'; enterobacter sakazakii-R: 5'-AAA CGA GAA TAA GCC GCG CAT T-3'; the internal positive control-F: 5'-TGT GAA ATA CCG CAC AGA TG-3'; and the internal positive control (IAC)-R:5'-AGC TGG CGT AAT AGC GAA G-3. According to the primer and the probe for specific detection on enterobacter sakazakii, the specific design is carried out aiming at the characteristics of enterobacter sakazakii, and thus the accuracy of the result is guaranteed.

The invention discloses an enzyme-linked immunosorbent assay diluent for whole blood and a preparation method and a use method thereof. The diluent is prepared from disodium hydrogen phosphate, monopotassium phosphate, a surfactant S9, PEG-6000, calcium chloride, glycerol, an anti-rheumatoid factor antibody and a preservative. The invention provides a sample diluent for diluting whole blood. Wholeblood is treated by the diluent, so that the influence of a whole blood sample on a detection result can be effectively removed, meanwhile, a background can be effectively reduced, false positive canbe removed, the detection sensitivity can be improved, the positive and negative contrast ratio can be increased, and the performance is obviously superior to that of a traditional sample diluent fordiluting serum or plasma. The diluent can be used for directly diluting whole blood, the process of extracting serum or plasma is reduced, the operation is convenient to simplify, certainly, the diluent can also be used for diluting serum, and the effect is good.

The invention relates to the technical field of in-vitro diagnosis, and especially relates to a detection kit for a human parainfluenzavirus3 (HPIV3) IgM antibody. The detection kit comprises an anti-human IgM antibody-magnetic particle conjugate, an HPIV3 antigen, a horseradish peroxidase labeled antibody of the HPIV3 antigen, a sample diluent and a chemiluminiscence substrate, wherein the enzyme-labeled antibody is an antibody without an Fc end. The detection kit adopts a capture method and is high in sensitivity and specificity. In addition, the capture method uses the natural HPIV3 as a bridge and uses the monoclonal antibody of the HPIV3 as a tracer, so that the problem that the specificity and the sensitivity are influenced due to insufficient purity of the antigen or incomplete sites when the antigen is used as the tracer is solved. The Fc end of the monoclonal antibody of the HPIV3 is cut off, so that false positive caused by a heterophile antibody existing in a sample can be eliminated.