198results about How to "Sensitive and accurate detection" patented technology

Molecular recognition-based electronic sensor, which is gateless, depletion mode field effect transistor consisting of source and drain diffusions, a depletion-mode implant, and insulating layer chemically modified by immobilized molecular receptors that enables miniaturized label-free molecular detection amenable to high-density array formats. The conductivity of the active channel modulates current flow through the active channel when a voltage is applied between the source and drain diffusions. The conductivity of the active channel is determined by the potential of the sample solution in which the device is immersed and the device-solution interfacial capacitance. The conductivity of the active channel modulates current flow through the active channel when a voltage is applied between the source and drain diffusions. The interfacial capacitance is determined by the extent of occupancy of the immobilized receptor molecules by target molecules. Target molecules can be either charged or uncharged. Change in interfacial capacitance upon target molecule binding results in modulation of an externally supplied current through the channel.

The invention relates to a cyclic RNA molecular marker for diagnosis of gastric cancer, the cyclic RNA molecular marker is characterized in that the cyclic RNA is hsa-circ-0001017, the invention also provides a method for detection of the cyclic RNA molecular marker in plasma, and the method comprises the following steps: (1) collecting blood, and extracting total RNA in the plasma; (2) performing reverse transcription of the total RNA into cDNA; (3) performing droplet digital PCR detection of a cDNA solution of the step (2) by use of specific amplification back-to-back primers and amplification upstream and downstream primers of housekeeping gene GAPDH, after the completion of the reaction, detecting fluorescence signal values of all droplets, setting a threshold, and determining whether the droplets include the cyclic RNA or the housekeeping gene GAPDH, wherein the droplets higher than the threshold are positive droplets, and the droplets below the threshold are negative droplets; and (4) counting the number of the positive droplets, and calculating the copy number of the hsa-circ-0001017 and the housekeeping gene GAPDH in the plasma for quantitative detection of the hsa-circ-0001017 and the housekeeping gene GAPDH in the plasma. Compared with the prior art, the advantages are that the hsa-circ-0001017 can be specifically expressed in plasma in patients with gastric cancer, and can be used as a new molecular marker for diagnosis of the gastric cancer.

The invention discloses a nuclear power plant pipeline leakage detection device and method based on distributed optical fiber temperature measurement. The nuclear power plant pipeline leakage detection device comprises a detection sensor unit, a signal receiving and transmitting processing unit and a data analysis and alarm unit. The detection sensor unit comprises an optical fiber and a fastening support, wherein the optical fiber is fixed to the portion above a high-energy pipeline through the fastening support. In the signal receiving and transmitting processing unit, a laser drive device is connected with the optical fiber through a wavelength division demultiplexer, the optical fiber is connected with the input end of a photoelectric detector through the wavelength division demultiplexer, and the output end of the photoelectric detector is connected with the input end of a signal processor. The data analysis and alarm unit comprises a PC terminal and an alarm indicator, wherein the output end of the signal processor is connected with the PC terminal, and the alarm indicator is connected with the PC terminal. The situation of high-energy pipeline system leakage in nuclear islands can be found in time, the leakage positions can be accurately positioned, the implementation foundation is provided for the leak-before-break design of the high-energy pipeline, and the safety of nuclear power plants is improved.

The invention provides a multiplex PCR primer detecting gene fusion through combination of anchored nested multiplex PCR and high-throughput sequencing. The multiplex PCR primer comprises a multiplex PCR specific primer group 1 and a multiplex PCR specific primer group 2, wherein the multiplex PCR specific primer group 1 consists of nucleotide sequences shown in SEQ ID NO:1-SEQ ID NO:32, and the multiplex PCR specific primer group 2 consists of nucleotide sequences shown in SEQ ID NO:33-SEQ ID NO:64. The invention further provides a method for detecting gene fusion through combination of anchored nested multiplex PCR and high-throughput sequencing. The detection method is high in universality and can be used for detecting fusion genes accurately and sensitively under the condition that structures of fusion genes are partially known or unknown.

The invention provides an ELISA (enzyme-linked immuno sorbent assay) detection kit for analyzing residual carbaryl, which comprises a kit body, a dismountable ELISA plate arranged in the kit body and a reagent arranged in the kit body, wherein every hole of the ELISA plate is coated with carbaryl coating antigen, the reagent comprises an anti-carbaryl nano antibody, a carbaryl standard solution, a second antibody of an enzyme marker, a buffer solution PBS, a scrubbing solution PBST, substrate liquid, a developing solution, a reaction stop solution and the like. In the detection process, the coating antigen adsorbed on a hole wall of the ELISA plate and the carbaryl to be detected compete with each other to react with the antibody, and the competitive result is shown through chromogenic reaction. By detecting the carbaryl with known concentration, and drawing a standard curve, the concentration of carbaryl to be detected can be calculated. The ELISA detection kit provided by the invention has the advantages that the residual carbaryl in water, soil and vegetables can be accurately and sensitively detected, the pretreatment process of a sample is simple and consumes short time, a large quantity of samples can be detected simultaneously, and the sample detection cost is far lower than that of a traditional instrument detection method.

The invention relates to a method for detecting an insulating resistance and releasing static electricity and a device thereof. An insulating detection point is set in each position of detected equipment which needs the insulating resistance detection; a direct current power supply is arranged outside the detected equipment; direct current with certain voltage is generated through the direct current power supply and is transported to the insulating detection point set in each position of the detected equipment which needs the insulating resistance detection; simultaneously, a voltage and current detection device is arranged in the middle of a direct current loop; the change of the direct current voltage and current of the insulating detection point set in each position of the detected equipment which needs the insulating resistance detection is detected and compared through the detection device; a monitoring device carries out voltage and current calculation to obtain the insulating resistance of the insulating point, judges whether the insulating resistance of the insulating point is normal and forewarns or warns according to the detected insulating resistance; simultaneously, according to the monitoring device, the output static voltage is determined, whether static release is needed is judged, and under the condition of needing static release, the static voltage is released for passing through a resistance network.

Provided herein are imaging cassettes for detecting a luminescent and/or radioactive signals. Such cassettes are useful in common biological assays, e.g., immunoassays, nucleotide detection assays, and other affinity assays.

The invention discloses an axial force sensor, which comprises an elastic body, wherein the elastic body is of a flat plate shape; an axis penetration through hole is formed in the middle of the plate surface; a plurality of bolt penetration holes are formed at the periphery of the elastic body; the whole shape of the elastic body is similar to that of a gasket of a flange disk; an annular stress slot concentric with the shaft axis penetration through hole is formed on each of the front plate surface and the rear plate surface of the elastic body, and the diameters of the annular stress slots are equal substantially; the stress slots are close to the axis penetration through hole; resistance strain gauges are attached to the stress slots and form a WheatStone balance bridge which is connected with an external electric appliance. The axial force sensor is low in height, small in size and similar to the gasket in the shape, can be conveniently assembled between the force applying shaft of the appliance and the flange disk or a stressed part at the connection shaft end of the appliance, is damaged difficultly, and is firm and high in lateral and unbalance loading resistance; and when the sensor is stressed by an axial load, part of the elastic body in each stress slot is effectively deformed, so that an axial force value can be sensitively and accurately detected.

The invention discloses a method of detecting the content of a preservative in a cosmetic, and the method comprises the following steps of (1) treating a sample to be detected; (2) preparing a preservative standard product stock solution and a standard series; (3) detecting by using a high performance liquid chromatography; (4) drawing a standard curve of a preservative standard mixed solution series, performing linear regression on the peak area of a preservative and the corresponding mass concentration, and calculating the content of the preservative in the sample to be detected according to an obtained equation of linear regression.

The invention discloses an assay kit used for detecting human papillomavirus, comprising human papillomavirus sequencing primer solution. The invention also discloses a preparation method and use method of the kit used for detecting high-risk type human papillomavirus. The kit of the invention can determine whether a sample to be detected contains HPV virus and concrete virus subtype. Identity label used for discriminating sample source is added on a DNA sample to be detected, thus meeting high throughout visitation requirement of detecting a plurality of persons at once. The kit of the invention exceeds the traditional detection means, sequence differential is positioned to basic group level, detection is more sensitive and accurate, and meanwhile probability of false positive pollution is avoided.

The invention relates to a method for rapid fluorescence detection of polynucleotide target objects simultaneously at room temperature and constant temperature. The method comprises the steps that at the constant temperature, single-chain binding proteins partially open parental chains of double chains of multiple templates to form single chains; recombinases are bonded with multiple pairs of primers to form complexes which are bonded to the parental chains under the action of accessory proteins, and multiple fluorescence probes are also bonded with a complementation region; DNA polymerases are bonded to the 3' terminals of the primers so as to perform subchain extension; exonucleases recognize tetrahydrofuran sites on the multiple fluorescence probes which are under the double chain condition, so that fluorophores and quenching groups are separated after digestion, and fluorescence is released; after the multiple fluorescence probes are cut, 3'-OH ends which are originally closed due to modification of the 3' terminals of the probes are exposed, and the DNA polymerases can further extend to form subchains; to-be-tested samples can be subjected to qualitative and semi-quantitative determination through detecting the shape of amplification curves and the strength of fluorescence signals. The method disclosed by the invention can be used for qualitative and semi-quantitative determination of multiple target objects simultaneously at room temperature and constant temperature.

The invention discloses a preparation method of water-soluble nitrogen-doped carbon quantum dots, comprising the following steps: Step 1, dissolving citric acid in ultrapure water to prepare precursor solution I, dissolving p-aminobenzamide in Prepare precursor solution II in pure water, uniformly mix precursor solution I and precursor solution II at a volume ratio of 1 to 10:1 to obtain a mixed solution; step 2, perform hydrothermal reaction on the mixed solution prepared in step 1, Water-soluble nitrogen-doped carbon quantum dots can be obtained. The invention adopts a one-step hydrothermal method to prepare water-soluble nitrogen-doped carbon quantum dots. The carbon source is rich and cheap, the preparation process is simple, the whole preparation process is pollution-free, non-toxic, green and environmentally friendly, and can be prepared in large quantities.

The invention discloses a method for analyzing and detecting trace ammonia nitrogen in complicated matrix by combining a fast distillation method with ion chromatography technology. The method comprises the following steps: firstly, carrying out distillation pretreatment on a complicated sample to enrich and extract ammonium ions, and then detecting by using an ion chromatography method. The sample pretreatment refers to extraction of ammonium ions from the sample by using a fast distillation method, and concretely comprises the following steps: firstly adding excessive base into the sample, heating and boiling so as to release ammonium ions in a manner of ammonia gas without carrying other interference ions, and absorbing ammonia gas at an absorption part with excessive acid, thus obtain purified ammonium ions. The extracted ammonium is detected by using the ion chromatography method. The method is excellent in the ammonium extraction effect, capable of eliminating the interference of sodium ions, potassium ions and other anodic ions to the ammonium detection, convenient and sensitive, and fast and accurate.

According to the present invention, there is provided a high-precision differential pressure sensor which is not affected by a considerable change in baseline pressure. A differential pressure sensor of the present invention comprises: a pair of diaphragms, each including a diaphragm portion capable of being deformed due to application of a pressure and a support portion for holding an outer peripheral edge of the diaphragm portion; a pair of fixed electrodes in disk-like form fixed to the support portions of the diaphragms; and a movable electrode including a disk-like electrode portion and shaft-like projections extending in opposite directions from a central portion of the electrode portion. The shaft-like projections extend at a right angle relative to the electrode portion, and the movable electrode is secured to central portions of the diaphragms through the shaft-like projections so that the electrode portion faces each of the fixed electrodes in a predetermined spaced relationship. The movable electrode is capable of moving so as to allow a distance between the electrode portion and each of the fixed electrodes to vary according to a difference between fluid pressures acting on the respective diaphragm portions of the diaphragms. A capacitance generated between the electrode portion and each of the fixed electrode changes due to a variance in the distance between the electrode portion and each of the fixed electrode, and a differential pressure is detected, based on this change in capacitance.

The invention discloses a preparation method and application of a double-color fluorescent gold-copper composite nano-cluster. The double-color fluorescent gold-copper composite nano-cluster is prepared from the raw materials, namely a chloroauric acid solution, a copper nitrate solution and glutathione by virtue of an oil-bath heating method. The double-color fluorescent gold-copper composite nano-cluster has the double-color fluorescent properties of emitting blue fluorescence (450nm) and orange red fluorescence (570nm) under the stimulation of a single wavelength, the blue fluorescence is hardly influenced by metal ions, and the intensity of the orange red fluorescence can be decreased or even the orange red fluorescence can be quenched by virtue of mercury ions and mercury compounds. Based on the characteristic, a fluorescence detection technique for detecting the mercury ions and the mercury compounds by virtue of a rate type fluorescence probe is constructed. The preparation method is simple, convenient and low in cost, the double-color fluorescent gold-copper composite nano-cluster has excellent fluorescent and chemical stabilities, and the disadvantages that a traditional dye is short in fluorescent lifetime, easy to photobleach and the like can be overcome; and a rate type fluorescent method is high in sensitivity and good in stability, does not require expensive instrument, can be applied to environmental monitoring and analysis and has wide application prospects.

The invention discloses an inhibin B enzyme-linked immunosorbent assay kit and an inhibin B detection method. The inhibin B enzyme-linked immunosorbent assay kit includes an ELISA plate coated with an anti inhibin B beta-subunit antibody, a biotin-labeled secondary antibody, and an avidin-labeled enzyme marker; a coating antigen used for preparation of the ELISA plate coated with the anti inhibin B beta-subunit antibody is a specific antibody aiming at an inhibitor B beta subunit; the biotin labeled secondary antibody is a biotin-labeled inhibin B alpha-subunit monoclonal antibody. The inhibin B detection method comprises that the inhibin B enzyme-linked immunosorbent assay kit is used for detection of the inhibin B. Therefore, the inhibin B enzyme-linked immunosorbent assay kit and the inhibin B detection method have the characteristics of high sensitivity, high specificity, time saving and the like, and can be applied to clinical medical batch detection of the inhibin B.