40results about How to "Realize qualitative and quantitative detection" patented technology

The invention discloses a visible and reversible fluorescent probe which comprises a cyanine fluorescent group and a benzothiazole group, and the general formula of the probe is shown in the description. The preparation method of the reversible fluorescent probe comprises the following steps: (1) dropwise adding phosphorus oxychloride into salicylaldehyde and paraformaldehyde for reaction, so as to obtain a product 1; (2) enabling the product 1 and hexamethylene-tetramine to react, so as to obtain a product 2; (3) enabling the product 2 and 2-aminobenzenethiol to react at the room temperature, so as to obtain a product 3; (4) enabling the product 3 and a compound 4 to react, so as to obtain the visible and reversible fluorescent probe. According to the ratiometric fluorescent probe provided by the invention, obvious color variation can be found out under natural light or an ultra-violet lamp, and the qualitative detection of sulfur dioxide gas can be implemented under natural light or a hand-held ultra-violet lamp, so that the operation is simple, high convenience and quickness are achieved, and the effect is remarkable; the fluorescent probe can effectively prevent interference from other impurities in samples, and is excellent in selectivity; in addition, the cumbersome pre-processing process of samples is avoided, so that the detection efficiency is high.

The invention discloses a method for recognizing quantitative chiral amino acid by using a reversible nano porphyrin fluorescence sensor, and belongs to the technical field of nano material preparation and chemical analysis detection. The reversible nano porphyrin fluorescence sensor for specifically recognizing quantitative proline, lysine and serine chirality adopts a CdTe quantum dot as a fluorescence probe, and self-assembled porphyrin prepared from a tetra-(4-pyridyl) zinc porphyrin tetrahydrofuran solution and cetyl trimethyl ammonium bromide (CTAB) as a fluorescence quencher, and with the specific combination of the florescence probe and the fluorescence quencher, an openable/closeable nano porphyrin fluorescence sensor can be prepared. The reversible (opening-closing-opening) nano porphyrin fluorescence sensor can be prepared under the action of the openable/closeable nano porphyrin fluorescence sensor with the chiral proline, lysine and serine. Compared with a conventional chromatographic method for recognizing amino acid chirality by separating, the method disclosed by the invention has multiple advantages.

The invention discloses a method for detecting an adsorbed-state microorganism in a chalcopyrite biological leaching process, and belongs to the technical field of biological leaching. The method disclosed by the invention comprises a washing method applied to an absorbed strain on the mineral surface, the calculation of total concentration of absorbed-state bacteria, and qualitative and quantitative detection method applied to the microorganism in a mixed bacteria system. Three different leaching systems applied to the chalcopyrite biological leaching, namely a pure thiobacillus ferrooxidans CUMT-1 system, a pure thiobacillus thiooxidans ZJJN-1 system and a mixed thiobacillus ferrooxidans and thiobacillus thiooxidans system (number concentration 1:1), are used as examples for verification, and the verification results prove that the method disclosed by the invention has the advantages of simple and easy operation implementation, low requirements for equipment, good specificity and high stability in the detection of the mixed system, and the like, can fast achieve the qualitative and quantitative detection on the absorbed-state microorganism in the biological leaching process, provides basic technical measures for improving the leaching rate, and is suitable for popularization and application.

The invention relates to a preparation method of an AFP (alpha fetoprotein) immunochromatographic test strip based on QDs (quantum dots). The preparation method comprises the following steps: QDs and an AFP antibody are coupled to prepare a fluorescent probe QDs@Ab1; the QDs@Ab1, AFP and another AFP antibody (Ab1') embedded in a test strip form a sandwich-like structure QDs@Ab1-AFP-Ab1' through the action between antibodies and antigens; the tumor marker AFP of primary hepatic carcinoma is qualitatively and half-quantitatively detected. Compared with the conventional product and technology, the test strip has the following advantages: the whole preparation process is simple and applicable to industrial production; the antigen concentration is in positive correlation with the fluorescence intensity of the probe, so that the strip can qualitatively and quantitatively detect AFP; the detecting process is low in cost, quite easy and convenient to operate and suitable for tumor screening in communities with high risk groups; a novel method for detecting tumor is established.

The invention relates to a preparation method of a quantum dot based prostate specific antigen immuno-chromatographic test strip. The test strip is composed of a sample pad, a bonder release pad, a chromatography membrane, and a water absorbing pad, wherein the sample pad and bonder release pad are prepared from preprocessed polyester fibers, and the chromatography membrane and water absorbing pad are made of a preprocessed cellulose nitrate membrane. A sample is dropwise added on the sample pad. The surface of the bonder release pad is painted with quantum dot marked alpha-prostate cancer antigen specific monoclonal antibody. Beta-prostate cancer antigen specific monoclonal antibody and goat-anti-mouse second antibody are coated in the chromatography membrane to form a T line (detection line) and a C line (quality control line). The water absorbing pad drives the liquid to be detected to flow. Compared to the conventional products and technologies, the provided preparation method has the advantages that the whole preparation process is simple, and the preparation method is suitable for industrial production. According to the fluorescent characteristics of quantum dots, the prostate specific antigen can be detected quantitatively and qualitatively, and the specificity is high. The operation is very convenient during the whole process, and the cost is low, so the provided test strip can be applied to tumor screening of high risk groups in communities. A novel method for detecting tumor is established.

The invention discloses a uric acid detection method based on silver triangular nanoflakes. The uric acid detection method comprises the following steps that the silver triangular nanoflakes are prepared; a to-be-detected sample is added into the silver triangular nanoflakes, then potassium rhodanide is added, and at this moment, if the absorption peak at 400 nm is weakened and the absorption peakat 575 nm rises again, it is expressed that the to-be-detected sample contains uric acid. The detection method is high in flexibility and selectivity.

The invention relates to a method for quantitative determination of catechins, and belongs to the technical field of nanomaterialpreparation and chemical analysis detection. The method for the quantitative determination of the catechins comprises the steps that a four-(4-pyridyl) zinc porphyrinphotosensitive effect of self-assembled nanocrystallization and ZnCdSe quantum dots are used for preparing and obtaining a reversible nanometer porphyrin fluorescence sensor with a nanometer effect in a buffle sollution system; and then strong acting force between the catechins and the nanometer porphyrin is used for opening up different degrees of specific changes of the reversible composite sensing interface between the nanometer porphyrin and the quantum dots, so that the quantitative detection ofthe catechins is realized. The method for the quantitative determination of the catechins is simple and controllable, has high sensitivity, good selectivity and high specificity of the detection method of the catechins, and can play an important role in the detection of the catechins.

The invention provides a method for detecting a novel coronavirus neutralizing antibody by using a BLI technology. The method comprises the following steps: capturing human ACE2 protein with the sameconcentration on the surface of a biosensor, and premixing novel coronavirus spinous process protein RBD with neutralizing antibodies to be detected with different concentrations respectively, respectively contacting each mixed solution with the human ACE2 protein captured on the surface of the biosensor, calculating the inhibition rate according to the change of the relative displacement intensity of the interference spectrum detected by a molecular interaction instrument based on the BLI technology, drawing an inhibition curve, and calculating IC50. The method is simple to operate, quick andefficient, coating, repeated sample adding and plate washing are not needed in the whole detection process, and experimental results can be obtained within 15 min. The detection reaction is carried out in a black pore plate, the detection of novel coronavirus neutralizing antibodies of a large batch of samples can be realized, and different from the traditional qualitative detection, the method has the advantages that the inhibition capability of different new crown neutralizing antibodies can be quickly compared by calculating the IC50 value.

The invention relates to a metal organic framework (MOFs) fluorescent probe for detecting tetracycline antibiotics (TCs) and a preparation method of the metal organic framework (MOFs) fluorescent probe, and also provides a fluorescence integration method and an application program for designing, analyzing and recognizing the overall pollution degree of the tetracycline antibiotics. According to the fluorescent probe, 5-aminoisophthalic acid (H2aip) is used as an organic ligand of a stable three-dimensional framework, transition metal Zn (II) is used as a metal source, and the fluorescent probe with unique response to TCs is synthesized. Meanwhile, based on a fluorescence integration method, the method is not limited to identification of a single antibiotic, the pollution degree of the TCs can be quantified through a TCs Analysis application program, through precise data processing and intelligent analysis, a new method is provided for measuring the overall pollution degree of the TCs, and the method is suitable for portable analysis and detection.

An electrochemical immunosensor for detecting CP4-EPSPS protein in crops comprises a glassy carbon electrode and a recognition element, the surface of the glassy carbon electrode is modified by a composite material, and the composite material is formed by ultrasonic treatment of graphene and amino-rich PAMAM; a gold-labeled antibody is used as a recognition element, a colloidal gold-labeled monoclonal antibody CP4mAb is connected to a composite material on the surface of a glassy carbon electrode in a covalent binding mode, and the electrochemical immunosensor is constructed after 5% BSA sealing. According to the invention, the introduction of gold nanoparticles improves the immobilization amount of an electroactive substance and amplifies a detection signal; The sensor is high in detection specificity and sensitivity for herbicide-resistant protein CP4-EPSPS, simple to operate, quick in reaction, high in sensitivity and good in stability, realizes quantitative detection for trace CP4-EPSPS antigen, and provides a new thought for high-sensitivity quantitative analysis of transgenic crops.

The invention discloses a functional multi-nitrogen heterocyclic ring fluorescent probe, and a preparation method and an application of the functional multi-nitrogen heterocyclic ring fluorescent probe, wherein the general structural formula of the functional multi-nitrogen heterocyclic ring fluorescent probe is shown in the specification, wherein R1, R2, R3 and R4 respectively and independently represent hydrophilic groups. The preparation method of the fluorescent probe comprises the following steps: taking bipyridine dimethylamine as a molecular skeleton, rearranging bipyridine dimethylamine after bipyridine dimethylamine is reacted with carbon disulfide to increase the molecular rigidity, and obtaining the organic probe giving out green fluorescence. The fluorescent probe is high in stability and is not easily photobleached. The fluorescent strength and the color of the probe are changed under the action of hypochlorous acid, so that the probe can be used to quantitatively and qualitatively detect the hypochlorous acid, the limit of detection is as low as 0.43 micrometer, and very high selectivity is acquired.

The invention provides a paper-based device based on a moving valve and molecular imprinting technology, and a manufacturing method and application thereof. The manufacturing method comprises the following steps of pattern design, chip fabrication, electrode construction on a paper base, chip connection, synthesis of a functionalized molecularly imprinted polymer layer, electrochemical polymerization, and elution of template molecules. The device is used for analysis and detection of biomarkers in serum samples. The invention provides a paper-based device based on moving valve and molecular imprinting technology, a manufacturing method and application thereof, and provide a novel device for clinically detecting biomarkers. The device is used for in-situ synthesis of biomarker molecularlyimprinted polymer, forms a clinical application method, creates a new strategy for antibody-free biomarker analysis, realizes the entire process from device fabrication to test result output on the paper-based device, and is economical, portable, high in speed.

The invention discloses a surface enhanced Raman scattering substrate material and a preparation method and application thereof. The substrate material is of a core-shell structure and comprises gold superparticles and a metal organic framework of a hollow structure, and the gold superparticles are arranged in the metal organic framework. A pore exists between the inner surface of the metal organic framework and the outer surfaces of the gold superparticles. The substrate material further comprises a functional modification material, and the functional modification material is combined on the outer surfaces of the gold superparticles through chemical bonds. According to the surface enhanced Raman scattering substrate material and the preparation method and application thereof, rapid gas capture, rapid adsorption, specificity and rapid quantitative detection of lung cancer respiratory markers can be realized.

The invention discloses a preparation method and application of a kit for simultaneously detecting various nafil substances based on a novel multi-quantum dot-protein polymer probe. The multi-quantum dot-protein immune probe is prepared by a one-step method based on a novel solvent-induced effect strategy, and the fluorescent immune probe with a large number of fluorescent quantum dots is prepared by mixing the quantum dots, the BSA and the antibody and utilizing hydrophobic interaction and pi-pi accumulation, so that the loading capacity of the quantum dots in the probe is improved, and the preparation method of the probe is simplified. Sildenafil, tadalafil and derivatives thereof are taken as detection objects, sildenafil and tadalafil antibodies and antigens are combined with the method to prepare a probe and a lateral flow immunochromatography test strip for specifically detecting sildenafil, tadalafil and derivatives thereof, a solid-phase extraction micro-fluidic chip is combined to construct a system for detecting nafil substances, and the system is used for detecting the sildenafil, tadalafil and derivatives thereof. Qualitative and quantitative detection of the 12 nafil drugs is achieved, the specificity is high, the sensitivity is high, the accuracy is good, and the detection result is reliable.

The invention belongs to the field of technologies for detecting and analyzing ozone, and particularly relates to a fluorescence probe for visually detecting ozone and a method for preparing the fluorescence probe. 2-(2-hydroxyphenyl) benzothiazole is used as a fluorophore for the fluorescence probe, 4-bromine-1-butene is used as a recognition group, bright green fluorescence can be emitted by thefluorophore in a solid state, the fluorescence is quenched after the fluorophore and the recognition group are connected with each other, the fluorescence probe capable of emitting weak blue light isgenerated, and the fluorophore capable of emitting the bright green fluorescence can be restored after reaction is carried out on the fluorescence probe and the ozone. The fluorescence probe and themethod have the advantages that the liquid-state and gas-state ozone can be visually, qualitatively and quantitatively detected by the fluorescence probe, and the fluorescence probe is good in selectivity and high in anti-interference performance.