348 results about "Chromogenic Substrates" patented technology

The invention relates to the immune analysis field, in particular relating to a method for performing an immunological test on biomolecules by avidin / streptavidin magnetic composite particles, which takes avidin / streptavidin magnetic composite particles as carriers, and comprises the following steps:, coating biotinylated antibody or antigen, adding a specimen to be tested and enzyme labeled antibody / enzyme labeled antigen / enzyme labeled anti-antibody, adding chromogenic substrate and testing.Biotin and avidin / streptavidin has strong binding capacity, can fix the antigen / antibody labeled by the biotin through the avidin / streptavidin labeled on the surface of the magnetic composite particles so as to use the system to test specific antibody / antigen. The test system has the advantages of high sensitivity, high specificity, high stability, strong adaptability and the like.

A monoclonal or polyclonal antibody directed against urokinase plasminogen activator receptor (u-PAR), or a subsequence, analogue or glycosylation variant thereof. Antibodies are disclosed which react with free u-PAR or with complexes between u-PA and u-PAR and which are capable of 1) catching u-PAR in ELISA, or 2) detecting u-PAR, e.g. in blotting, or 3) in radioimmunoprecipitation assay precipitate purified u-PAR in intact or fragment form, or 4) is useful for immunohistochemical detection of u-PAR, e.g. in immunostaining of cancer cells, such as in tissue sections at the invasive front, or 5) inhibits the binding of pro-u-PA and active u-PA and thereby inhibits cell surface plasminogen activation. Methods are disclosed 1) for detecting or quantifying u-PAR, 2) for targeting a diagnostic to a cell containing a u-PAR on the surface, 3) for preventing or counteracting proteolytic activity in a mammal. Methods for for selecting a substance suitable for inhibiting u-PA / u-PAR interaction, for preventing or counteracting localized proteolytical activity in a mammal, for inhibiting the invasion and / or metastasis comprise the use of the antibodies and of nude mice inoculated with human cancer cells which are known to invade and / or metastasize in mice and having a distinct color, f.x. obtained by means of an enzyme and a chromogenic substrate for the enzyme, the color being different from the cells of the mouse.

A test medium and method for detecting, quantifying, identifying and differentiating up to four (4) separate biological materials in a test sample. A test medium is disclosed which allows quantifying and differentiating under ambient light aggregates of biological entities producing specific enzymes, which might include general coliforms, E. coli, Aeromonas, and Salmonella in a single test medium. A new class of nonchromogenic substrates is disclosed which produce a substantially black, non-diffusible precipitate. This precipitate is not subject to interference from other chromogenic substrates present in the test medium. In one embodiment, the substrates are selected such that E. coli colonies present in the test medium show as substantially black, general coliforms colonies show in the test medium as a blue-violet color, Aeromonas colonies present in the test medium show as a generally red-pink color, and Salmonella colonies show as a generally teal-green color. Other microorganisms and color possibilities for detection and quantification thereof are also disclosed. An inhibitor and method for making a test medium incorporating the inhibitor are disclosed.

The invention relates to a method for detecting trivalent arsenic in water body through a colourimetry by using protoheme peroxidase catalytic activity, chlorhematin has horseradish peroxidase activity, under the existence of hydrogen peroxide, a chromogenic substrate 3,3', 5,5'-tetramethyl benzidine (TMB) can be catalyzed to generate an oxidation reduction reaction, the solution have variable color change by naked eyes, the addition of a nucleic acid aptamer can inhibit catalytic activity, after adding the trivalent arsenic in the solution, the catalytic activity obtains recovery, so that the color of a whole system enables substantial change, the absorbance and trivalent arsenic concentration at 442nm present a direct proportion relation, thereby the method can be used for detecting the trivalent arsenic of the water body. The detection method provided by the invention has the advantages of high sensitivity and good selectivity, the lowest detection limit is 1ppb, the operation is simple, and a large-scale apparatus is not required, and the method can be used for detecting the trivalent arsenic in drinking water.

Isolation plating medium of a first color for the identification of Listeria sp. and Listeria monocytogenes and Listeria ivanovii containing a first chromogenic substrate that responds to phosphatidylinositol-specific phospholipase C enzymes to release precipitate of a second color into the medium and a second chromogenic substrate that responds to beta-glucosidase enzymes to release precipitate of a third color into the medium, and said first, second and third colors contrasting with each other.

The invention relates to technical field of immunodetection, particularly relates to a kit for joint detection of ovarian cancer tumor markers HE4 and CA125 as well as a preparation method and application thereof. According to the kit provided by the invention, silanization treatment is performed on horse radish peroxidase, so that the possibility that the horse radish peroxidase becomes a phosphoric acid receptor in a process of catalyzing a chemiluminescent substrate to emit light by a alkaline phosphatase is blocked, the problem that the existence of horse radish peroxidase disturbs the cataluminescence of the alkaline phosphatase is solved, so that the size of the light intensity caused by the alkaline phosphatase on magnetic particles is detected by chemiluminescent substrate liquid first, the size of chromogenic absorbancy caused by the horse radish peroxidase is detected by chromogenic substrate liquid and the simultaneous detection on HE4 and CA125 of a sample is realized. Thekit provided by the invention has the advantages that the detection process is simple, the reaction time is short, the reagent dose is less, the cost is reduced, the sensitivity is high, the repeatability and stability of the reagent are good.

The invention discloses a chromogenic medium of a coliform group and a quick detection card thereof. The medium contains peptone, yeast extract, lactose, common salt, sodium pyruvate, SDS, sodium dihydrogen phosphate, a specific enzyme chromogenic substrate and IPTG. The quick detection card consists of, in a bottom-up order: a negative film, a water absorption and moisture retention layer, a medium layer and a covering membrane, with the above medium adsorbed on the medium layer. The chromogenic medium of a coliform group and the detection card that are provided in the invention can detect coliform groups in drinking water, surface water or foodstuff, with short detection time and high efficiency. The chromogenic medium and the detection card of the invention can conduct qualitative detection to coliform groups, and simultaneously can carry out quantitative analysis. And a positive result has obvious color development and is convenient for observation, odds for emergence of false positive and false negative can be reduced, and the detection result is accurate.

The invention discloses a chromogenic medium for detecting salmonella, which belongs to the fields of food safety and clinical microbiological detection. The culture medium contains agar, peptone, beef extract powder, sodium chloride, a surfactant, cholate, an enzyme inducer, an octoate enzyme chromogenic substrate, a beta-galactosidase chromogenic substrate, a hexosaminidase chromogenic substrate and robiocina. The chromogenic medium disclosed by the invention is used for detecting salmonella, has high detection sensitivity and high specificity, and can be used for initially identifying strains directly according to the color of a colony; the chromogenic medium has high operability, and suitable for treating large-reflux samples, and can be used for comprehensively, systematically and accurately detecting and initially identifying salmonella in food production, clinical disease diagnosis and the environment; and a new way is provided for rapid detection of microorganisms.

The invention relates to a kit for detecting food-borne pathogenic bacteria, which comprises 12 groups of primers and probes thereof, wherein in the primers, the 5' ends of downstream primers are all tagged with biotin. The kit amplifies nucleic acid in a sample to be detected by utilizing the primers, and a formed biotinylated product and a probe fixed on the surface of a chip are hybridized to form a probe-biotinylated product compound; an alkaline phosphatase-streptavidin conjugate is combined with the probe-biotinylated product compound, and then chromogenic substrate which is tetranitroblue tetrazolium chloride / 5-bromine-4-chlorine-3-indolyl-phosphate (NBT / BCIP) is reacted with alkaline phosphatase to undergo a colour generation (bluish violet) reaction; and whether the sample to be detected contains the pathogenic bacteria to be detected is detected by interpreting whether a specific site has colour generation. The kit has the advantages of high detection throughput, high speed, high sensitivity, high specificity and great practicability. The invention also provides the method for detecting the food-borne pathogenic bacteria by adopting the detection kit.

The invention relates to candida chromogenic medium, a detection kit and a detection method, belonging to the technical field of microbial diagnosis, in particular to the cultivation and identification of yeast in medical microbiology specimens, drugs and medical equipment sanitary inspection samples, public health surveillance samples and food (including cosmetics) sanitary inspection samples. The chromogenic medium of the invention is composed of basic medium, mixed chromogenic substrate and bacteriostat, wherein the mixed chromogenic substrate consists of aminocaproic glucosidase and alkaline phosphatase substrate, and candida specific enzyme is added into the mixed chromogenic substrate. The detection kit of the invention consists of the chromogenic medium, identification paper A containing enzyme substrate 5-bromo-4-chloro-3-indolyl-N-acetyl-beta-D-aminogalactose and identification paper B containing enzyme substrate 5-bromo-4-chloro-3-indolyl-beta-D- glycopyranoside. In the invention, the candida chromogenic medium and the detection kit have the advantages of low cost and simple configuration, and the method can be applied to the separation and identification of candida rapidly, simply and accurately.

The invention relates to the medical field of immunoassay, and concretely provides a dissociate human chorionic gonadotrophin beta-subunit magnetic particle chemiluminescence quantitative assay kit having the advantages of simplicity, rapidness, high sensitivity, wide linear range and good stability, and its preparation method. The method combines a magnetic particle immune separating technology to apply an enzymatic chemiluminescence substrate on the basis of enzyme-linked immunosorbent assay, and allows an optical signal generated by the detection of the luminescence substrate to substitute a chromogenic substrate in enzyme immune assay, so the method has the advantages of substantially improved sensitivity, simple operation and wide practicality, can be applied to open semi-automatic chemiluminescence detectors, can also be applied to full-automatic measure systems, and can realize batch and fast detection, low use cost, and easy popularization and application.

A device and method simultaneously detects and enumerates two groups of microorganisms in a test sample, utilizing a single test container. In the container liquid growth media, a chromogenic substrate and a fluorogenic substrate are mixed with the test sample. The test container is incubated to allow bacterial growth and metabolism. Spectral changes of the substrates are dynamically detected using two external light sources aimed at a transparent section of the test container, and a single external photo detector. One light source operates in the visible band and the second in the long ultraviolet band. The two dynamic time patterns generated by the two substrates are analyzed in real time to determine the presence or absence of each microorganisms group and to enumerate their original concentrations in the test sample.

The invention discloses a chromogenic medium used for detecting esherichia coli O157:H7. The medium comprises agar, peptone, beef extract powder, sodium chloride, sorbitol, inositol, neutral red, beta-galactosidase chromogenic substrate, beta-glucuronidase chromogenic substrate, isopropyl-beta-D- thiogalactopyranoside, natrium taurocholicum, potassium tellurite and cefixime. The chromogenic medium used for detecting esherichia coli O157:H7 of the present invention has the advantages of high sensitivity, good specificity, direct bacterial strain discrimination according to colony color, short detection period and strong operationality, is suitable for treating high-reflux samples, is capable of comprehensively, systematically and accurately detecting and preliminarily identifying the esherichia coli O157:H7 in food production and environment, and provides a novel approach for rapidly detecting the microbes.

The invention relates to a process for the research and development of a colon-bacillus composite and speedy chromogenic identification reagent. The process is characterized in that: 1. First, the quality control method is determined through activation identification and biochemical identification of coliform groups, salmonella, shigella and staphylococcus aureus; 2. Basic nutrients are selected according to the needs of target strains; 3. It is verified by the auxanogram method that proper nutrition environments, carbon sources, nitrogen sources, minerals, microelements, nutrilits, etc. are all necessary for the growth and breeding of microbes; without any one thereof, the microbes can not grow, metabolize and breed normally; 4. A visualization reagent, a masking reagent and a synergistic agent are selected; 5. Composite selection is conducted; 6. The feasibility of the composite selection formula is verified through tests, verifications and examinations on the indexes of a speedy chromogenic substrate, including the specificity test, the sensitivity test, the real sample inspection, the false negative and false positive strain identification, the stability test, the repeatability test, the competing strain and mixed bacterium interference test, the detection time and detection rate tests. 7. The most suitable formula is selected through a factor level orthogonal combination test.

The invention discloses a high throughput screening method of aminopeptidase and a high-yield strain thereof, relates to a high throughput screening method of aminopeptidase and a high-yield microorganism bacterial strain thereof. The method comprises the following steps of: vaccinating a single colony in the hole of a deep-hole plate I on a medium containing a seed liquid, performing shaking cultivation, vaccinating the seed liquid in the hole of the deep-hole plate I correspondingly into the hole of a deep-hole plate II equipped with a fermentation medium, performing shaking cultivation, and centrifuging the deep-hole plate II to obtain the supernatant crude enzyme; adding a buffer solution and a chromogenic substrate solution or fluorogenic substrate solution in the micropore of an elisa plate, adding the dilute crude enzyme to be tested, carrying out water-bath reaction for 10-30 minutes at 30-70 DEG C, adding a 30-50% acetic acid solution immediately after the water-bath reaction and terminating the reaction; and measuring the absorbance or fluorescence intensity of the reaction liquid by a microplate reader, and calculating the enzyme activity according the standard curve and the dilution ratio of the crude enzyme. According to the invention, the goals of high throughput cultivation, high throughput preparation of crude enzyme and the high throughput test of the enzyme activity are achieved.

The invention relates to an enzyme-linked immunosorbent assay substrate solution. The substrate solution comprises a chromogenic solution (A) and a chromogenic solution (B). The substrate solution provided by the invention can be stably stored for two years at the temperature of 2 to 8 DEG C, the chromogenic effect can be kept for 1h, and the chromogenic strength is obviously improved; meanwhile, a background is not added, so that the detection sensitivity is improved, the aims of stability and high efficiency are achieved, and various requirements of an enzyme-linked immunosorbent assay kit on the chromogenic substrate solution are met.

The invention discloses an immunoassay method based on a platinum nanoparticle mimic enzyme. The immunoassay method comprises the following steps: step one, preparing the platinum nanoparticle mimic enzyme through a sodium borohydride reduction method; step two, labeling the platinum nanoparticle mimic enzyme onto an antibody, and forming a platinum-labeled antibody nanoprobe; step three, forming an immune complex by the antibody coated on an enzyme-labeled microporous plate, a sample to be detected and the platinum-labeled antibody nanoprobe through a sandwich type immunoassay reaction mode; and step four, adding a chromogenic substrate solution to perform chromogenic detection. The immunoassay method based on the platinum nanoparticle mimic enzyme can be used for the colorimetric immunoassay of a macromolecular object; the related nanoprobe complex is simple in preparation process and low in cost; and the immunoassay method is simple, rapid in color development, and high in sensitivity, thereby providing a novel enzyme-free, sensitive and stable method for the clinical immunological detection.

An enzyme-linked detection kit for detecting VEGF. A kit body contains an enzyme-linked reaction plate coated by a VEGF acceptor and a monoclonal antibody, an enzyme conjugate labelled by HRP and configured by antibody and a protective agent, a freeze-drying powder of the VEGF protein as a positive contrast, a protein freeze-drying powder as a negative contrast, a sample diluent, a PBST concentrated lotion, a chromogenic substrate configured by 3,3',5,5'-tetramethyl benzidine, 2MH2SO4 as a stopping solution and a seal plate gummed paper. The kit can be used in diagnosis and prognosis of cancer, angiopathy, diabetes, retinopathy and rheumatoid arthritis, and has advantages of accuracy, specificity, sensitivity, stability and convenience, etc.

Provided is a method of identifying a target cell using a virus. The method includes infecting the target cell with the virus by contacting the virus to the target cell and culturing the target cell to propagate the virus; adding a chromogenic substrate to the resultant cell culture to induce enzyme reaction converting the chromogenic substrate to a chromogenic product; and measuring an optical signal emitted from the chromogenic product, wherein the virus contains in its genome a gene encoding an enzyme capable of converting the chromogenic substrate to the chromogenic product and a gene encoding a ligand allowing the virus to specifically bind with a receptor of the target cell to infect the target cell with the virus.

The present invention relates reagent kit for IgG immunoblotting diagnosis of SARS coronavirus antibody. The reagent kit consists of solid film, antiantibody of enzyme label and corresponding chromogenic substrate. The solid film is obtained through purifying SARS coronary totivirus lysate liquid antibody or recombining mixed antigen, gel electrophoresis to separate and transferring to film. The antiantibody of enzyme label is compounded with rabbet's antihuman IgG labeled with horseradish peroxidase or sheep's antihuman IgG labeled with alkaline phosphatase, 0.01 % concentration thimerosal as protecting agent, ox serum protein in 1 wt% and PBS in pH 7.4 in 0.01 M. The present invention may be used in detecting several kinds of antigen and antibody in clinical test department and sanitary epidemic prevention department.

The invention discloses a reagent for detecting antithrombin activity, including reagent 1 and reagent 2, wherein: reagent 1 is a chromogenic substrate of FXa, and reagent 2 is a diluent containing FXa and heparin; wherein the chromogenic substrate of FXa is selected from From the following: CH 3 SO 2 ‑D‑Leu‑Gly‑Arg‑p‑nitroanilide·AcOH; CH 3 OCO‑D‑CHG‑Gly‑Arg‑p‑nitroanilide·AcOH; CH 3 OCO‑D‑CHA‑Gly‑Arg‑p‑nitroanilide AcOH; Benzoyl‑Ile‑Glu‑Gly‑Arg‑p‑nitroanilide HCl; Suc‑Ile‑Glu(γ‑Piperidyl)‑Gly‑Arg‑p‑nitroanilide HCl; N-α-Z-D-Arg-Gly-Arg-p-nitroanilide 2HCl; Boc-D-Arg-Gly-Arg-p-nitroanilide 2HCl; Acetyl-D-Arg-Gly-Arg-p ‑nitroanilide·2HCl; 4‑Nz‑D‑Arg‑Gly‑Arg‑p‑nitroanilide·2HCl; 4‑Mbs‑D‑Arg‑Gly‑Arg‑p‑nitroanilide·2HCl. The invention has good detection stability and repeatability, high sensitivity and accuracy, can accurately reflect the activity of antithrombin, and can find patients with abnormal antithrombin activity in the body, thereby providing a basis for treatment.

The invention discloses a premature rupture of membrane (PROM) detection kit using an intercellular adhesion molecular (ICAM)-1 as an examination index. The kit comprises a perforated plate coated with an ICAM-1 monoclonal antibody, biotin-labeled ICAM-1 monoclonal antibody (biotin-ICAM-1Ab) examination fluid, aidin-horseradish peroxidase combined with the biotin-labeled ICAM-1 monoclonal antibody, chromogenic substrate 3',3',5,5'-tetramethylbenzidine and ICAM-1 protein standard. A preparation method of the kit comprises the following steps of: (1) preparing the perforated plate coated with the ICAM-1 monoclonal antibody; (2) preparing the biotin-labeled ICAM-1 monoclonal antibody examination fluid; and (3) preparing the aidin-horseradish peroxidase, the chromogenic substrate 3',3',5,5'-tetramethylbenzidine and the ICAM-1 protein standard.

The invention provides a detection vessel capable of rapidly culturing and detecting moulds and yeasts at the same time. A biochemical reaction characteristic of microorganisms is utilized, types and reaction conditions of endoenzymes of the microorganisms are determined as main bases for microorganism classification and identification, a microorganism specific enzyme chromogenic substrate is added into an isolation medium or a selective medium, and when target bacteria grow on the medium, the chromogenic substrate can be degraded by specific enzymes and metabolites in special colors can be generated to realize specific colors or forms of colonies, thereby implementing culturing and detection of the microorganisms in a sample. The detection vessel has the advantages of convenience in operation, low cost, labor saving, simple judgment result, reliable detection result, short detection time and the like, and can play an important role in microorganism detection, and accuracy of a detection result reaches 90 percent or over 90 percent of a national standard detection method.

The invention provides a novel ELISA (Enzyme Linked Immunosorbent Assay) method with high detection sensitivity. The detection sensitivity of the novel ELISA method can reach 100 times of that of an existing ELISA method. In the novel ELISA method, a more sensitive novel fluorogenic substrate is used for replacing a chemical chromogenic substrate in the conventional ELISA method; moreover, a high-efficiency stable enzyme capable of catalyzing the fluorogenic substrate to generate a luminescent effect is used as a marker enzyme so as to realize that the luminescent effect of the substrate reaches the minimum enzyme quantity required for the detectable level; the novel ELISA method also uses a gold nanoparticle coupling streptavidin system with excellent biocompatibility for realizing an amplification effect of an enzymatic reaction; integration of improvement measures on the three aspects finally implements great improvement on the detection sensitivity of the ELISA method.

The invention relates to a chromogenic media of salmonella, a detection kin and a detection method, which belongs to safety monitoring field of food microorganisms. The detection kin is composed of chromogenic media of mixed chromogenic substrates M-galactoside added with bacteria-specific enzyme of 0.1 to 0.5 grams, buffered peptone water medium of enrichment fluid A, and brilliant green enrichment fluid B of sodium tetrathionate. In the time of detecting, a food sample is pretreated, the enrichment fluids A and B are sequentially utilized to perform enriched culture, the secondary enrichment fluids are finally inoculated to be cultured on the chromogenic media, and the appearance of basic fuchsin bacterial colony which is smooth, slightly convex, and uniform in the edge and of which the diameter is 1 to 3 millimeters proves the existence of the salmonella in the sample. The chromogenic media is low in costs, and the detection kin is simple in configuration. The detection method has the advantages of high detecting sensibility, short cycle, strong operability and applicability for the treatment of samples of high flux, which is easy in industrialization production and capable of being widely applied in the fields of food sanitation, environmental monitoring and the like.

The invention discloses a dual-mode separation type immunosensor based on enzyme-induced biological etching. A cadmium sulfide / zinc oxide nanorod array CdS / ZnO NRs covers / is prepared at the surface ofa three-dimensional reduced graphene oxide r-GO as a photoelectrode; gold nanoparticle dual-cone Au NBPs are adopted as a multicolor chromogenic substrate; horse radish peroxidase (HRP) is used to connect with photo-electrochemical immunoassay and colorimetric detection, wherein Cd / ZnO NRs / r-GO generates biological etching through the enzymic catalytic reaction induced by HRP so as to form lightcurrent change, and hydroxyl radical generated by catalytic oxidation of the hydrogen peroxide by the HRP is used for biological etching of Au NBPs to form gold nanoparticles with different sizes andshapes so as to display the color change and the blue shift of an LSPR peak. The method adopts a lipidosome to package a lot of HRPs and load more Ab2 to effectively amplify response signals so as tofurther improve the accuracy of the detection.

A plating medium for the presumptive identification of Bacillus cereus, Bacillus thuringiensis and / or Bacillus anthrasis that includes a nutrient base to facilitate growth of Bacillus cereus, Bacillus thuringiensis and Bacillus anthrasis, a chromogenic substrate that changes color responsive to the presence of PC-PLC enzymes, and an ingredient that promotes the expression of the PC-PLC enzyme. In a preferred embodiment, the medium includes a second chromogenic substrate that changes color responsive to the presence of PI-PLC enzymes and an ingredient that promotes the expression of the PI-PLC enzyme.

The invention discloses a liquid ready-to-use antithrombin III activity determination reagent which comprises a reagent 1 and a reagent 2; the reagent 1 is prepared from FXa, heparin, a buffer solution and a protective agent; and the reagent 2 is prepared from a chromogenic substrate of the FXa and mannitol. The liquid ready-to-use antithrombin III activity determination reagent provided by the invention has the advantages of high sensitivity, good stability and convenience in use.

The invention discloses a micro-RNA-21 ultra-sensitive detection method based on double-enzyme signal cascade amplification. The method includes the steps: horseradish peroxidase enzyme-labeled probepreparation: coupling carboxylation polystyrene micro-spheres and horseradish peroxidase enzyme through DNA (deoxyribonucleic acid) single chains by an EDC (ethylene dichloride) carboxyl and amino coupling method; double-chain specific nuclease assisted target recycling: specifically cutting the DNA single chains complementarily paired with RNA (ribonucleic acid) to be detected in a probe by double-chain specific nuclease, triggering target circular reaction, releasing more horseradish peroxidase enzyme by cutting and amplifying signals; horseradish peroxidase enzyme signal amplification: collecting the horseradish peroxidase enzyme released in supernatant by cutting, adding a TMB (tetramethylbenzidine) chromogenic substrate, realizing naked-eye qualitative diagnosis by color change, and realizing enzyme-labeled quantification according to change of absorbance values. The difference of micro-RNA family members is effectively distinguished, and the method is suitable for community tumorscreening of high risk groups and has great application values in biomedical research and clinical diagnosis.