14results about How to "Improve detection limit" patented technology

The invention discloses a biosensor based on an ultraviolet light triggered bio-barcode release technology (OBCA) and construction and application of the biosensor. The biosensor comprises nucleic acid functionalized silver nanoparticles, nucleic acid functionalized magnetic beads and a CRISPR (clustered regularly interspaced short palindromic repeats) / Cas12a detection system, the DNA bar code modified on the surface of the silver nanoparticle contains a light cleavable linker, a CRISPR / Cas12a activation sequence and a target capture sequence I, and a DNA capture probe containing a target capture sequence II is fixed on the surface of the magnetic bead through biotin-streptavidin action. During detection, target miRNA mediates two capture sequences to form a sandwich compound, after magnetic separation and thermal denaturation elution, 365nm ultraviolet radiation releases DNA bar code fragments, and the Cas12a trans-cleavage fluorescence quenching reporter probe is activated to generate a signal. According to the method, nucleic acid amplification and reverse transcription are not needed, the detection limits of miR-21, miR-155 and mi-210 respectively reach 158.94 aM, 763.56 aM and 197.82 aM, single-base mismatch and precursor miRNA can be distinguished, the serum sample detection result is highly consistent with that of RT-PCR, and the method is suitable for high-sensitivity quantitative detection of miRNA.

The invention discloses a dual-mode detection kit for highly sensitive detection of ERalpha based on HRP-streptavidin. The dual-mode detection kit comprises the following raw materials: a glassy carbon electrode, 1-AP-CNHs, AuNPs, Sh-Apt, MCH, Bio-Ab, and HRP-streptavidin. The invention successfully constructs an electrochemical detection kit for detecting ERalpha with high sensitivity on the basis of the 1-AP-CNHs / AuNPs composite material. According to the invention, due to the redox activity of HRP-streptavidin, the HRP-streptavidin and H2O2 are subjected to redox reaction to generate a current signal; in addition, hydrogen peroxide can be catalyzed to generate. OH free radicals, and the free radicals can oxidize TMB to generate blue products, so that colorimetric reaction is initiated, and ERalpha can be detected more accurately. The electrochemical-colorimetric dual mode of the 3D 1-AP-CNHs / AuNPs composite material and the HRP-streptavidin for high-sensitivity detection of the ERalpha disclosed by the invention greatly improves the detection accuracy. The kit has the advantages of good selectivity, strong stability, high sensitivity, anti-interference performance, environmental protection and the like.

Use of a compound, microarray chip substrate, microarray chip and use and method thereof. The present application provides use of a compound, or a geometric isomer, tautomer, isotopically labeled, hydrate, solvate or salt thereof in chip surface modification. Also provided is a microarray chip substrate modified by the compound, and a microarray chip comprising the microarray chip substrate. The microarray chip substrate of the present application can greatly improve the surface modification function by surface modification, improve nucleic acid synthesis yield, amplify detection signal, and avoid non-specificity and cross-talk. It has a wide application prospect.

This invention discloses a three-modal, two-color lateral flow immunochromatographic test strip based on phenylboronic acid gold nanoflowers and its detection method. This test strip can simultaneously perform qualitative and quantitative tests, with the qualitative mode capable of detecting concentrations as low as 10. 3 Pathogenic microorganisms at CFU / ml; the lowest detectable concentration in colorimetric quantification mode is 10. 3 Pathogenic microorganisms at CFU / ml; the lowest detectable concentration using photothermal and Raman quantitative modes is 10. 2 The invention detects pathogenic microorganisms at cfu / ml levels; the detection can be completed within 15 minutes, and the test results can be observed with the naked eye; the three-modal LFIA improves the sensitivity, accuracy, flexibility and practicality of the detection. The invention has strong specificity for pathogenic microorganisms, high sensitivity, convenient and fast detection process, and safe and reliable test results.

This invention discloses a wide dynamic range substrate reagent, belonging to the field of biological detection reagent technology. The reagent consists of the following components: citric acid, 9.6 g / L; 3,3',5,5'-tetramethylbenzidine, 0.29 g / L; 3% hydrogen peroxide solution, 3 mL / L; 1 g / L polyvinyl alcohol; 0.5 g / L copovidone W-735; 0.5 g / L dimethyldiallylammonium chloride-acrylamide copolymer; 1 g / L PVP K30; and Tween 20, 0.005 g / L. mL / L; polyethylene glycol 10g-50g / L; pure water, balance. This invention, by adding specific polyethylene glycol and synergistically combining with other components, significantly reduces the reagent background signal and improves detection sensitivity; effectively broadens the detection dynamic range and increases the detection upper limit of high-concentration analytes; improves the linear correlation between signal and concentration; and enhances the thermally accelerated stability of the reagent. This reagent has comprehensive performance and is especially suitable for ELISA detection systems with high sensitivity and wide detection range.

The invention discloses a method for identifying unknown organic phosphodiesters in an environment based on a diazomethane derivatization technology. The method comprises the following steps: S1, establishing an OPDEs suspicious database; s2, carrying out methyl derivatization on the OPDEs to be detected; s3, carrying out suspicious screening on the OPDEs; s4, determining characteristic fragments of the derivatization OPDEs; and S5, carrying out non-targeted screening on the OPDEs. According to the suspicious-non-targeted comprehensive screening method for the unknown OPDEs in the environmental sample, the limitation that an OPDEs analysis method in the environment can only recognize known types of OPDEs can be solved, and comprehensive recognition of the unknown OPDEs in the environmental sample can be achieved.

The application provides a method for determining ultra-low content thallium in iron ore, which adopts an extraction separation method to extract thallium from a multi-component test solution containing iron, calcium, aluminum and silicon, realizes separation and enrichment, and then determines by using an inductively coupled plasma emission spectrometer; the application utilizes the chemical properties of thallium and alkane compounds containing active oxygen substituents represented by 4-methyl-2-pentanone, adopts an extraction method for separation and enrichment, establishes a suitable analysis method, and completes the detection of ultra-low content thallium in ore.

The application discloses a kind of based on surface acoustic wave activation electrochemical microorganism device and method, the device includes electrolytic cell main body, working electrode, surface acoustic wave excitation module;The working electrode, attached electrochemical microorganism;The surface acoustic wave excitation module, by applying alternating signal generates surface acoustic wave, surface acoustic wave spreads to working electrode area, and acts on the electrochemical microorganism attached on working electrode.The method includes that reference electrode, working electrode, counter electrode are accessed electrochemical workstation;Start surface acoustic wave excitation module, and alternating signal is applied to the interdigital transducer in this surface acoustic wave excitation module, for generating Rayleigh wave;Through peristaltic pump, bacteria liquid is placed into device, and after flowing through working electrode, it is discharged to sterile container, and this step is recycled 3-5 times.

The present application belongs to the technical field of aquatic product refrigeration house, and particularly relates to an aquatic product refrigeration house micro-environment gas component monitoring system and method. In the system, the MEMS gas detection module is used to realize real-time online monitoring of the gas component of sample gas in the micro-environment of the aquatic product refrigeration house; the temperature monitoring and position module is used to monitor the temperature information and position information in the aquatic product storage process in real time; the information gathering and adaptive analysis processing module is used to analyze and determine the gas component signal monitored by the MEMS gas detection module, and establish an aquatic product quality marker gas component database, and at the same time, an analysis prediction model is constructed by combining the position, temperature and gas concentration threshold value to regulate and control the micro-environment of the refrigeration house; the early warning and regulation module is used to generate an early warning signal according to the abnormal information of the cold chain transportation, and notify the user or manager to regulate and control the aquatic product refrigeration house; the information interaction module is used to display the information of each module in real time.

The present application relates to the technical field of gas detection, and provides an inert gas measuring device, which comprises a laser, a first beam splitter, a hollow cathode discharge cavity, two optical filters, two photodetectors and a data acquisition card; the laser is used for emitting laser; the first beam splitter is used for splitting the laser into two beams, one of which is emitted to one photodetector after passing through the hollow cathode discharge cavity and one optical filter, and the other of which is emitted to the other photodetector after passing through the other optical filter; the hollow cathode discharge cavity is filled with inert gas; the data acquisition card is connected with the two photodetectors and is used for collecting signals of the two photodetectors and outputting the metastable particle number density in the hollow cathode discharge cavity. The scheme can improve the plasma density generated by discharge and the metastable atom conversion efficiency, reduce the detection limit under the condition of ensuring the measurement accuracy, and accurately measure the inert gas content.

This invention relates to a microfluidic biosensing platform based on upconversion luminescence, comprising: an upconversion luminescence biosensor for specifically identifying EDCs; and a microfluidic chip for integrating the mixing, reaction, separation, and detection of the upconversion luminescence biosensor and a sample to be tested; the microfluidic chip comprising: a sample inlet for introducing the upconversion luminescence biosensor and the sample to be tested; an arc-shaped channel, the inlet of which is simultaneously connected to the sample inlet of the upconversion luminescence biosensor and the sample inlet of the sample to be tested, wherein the arc-shaped channel is used for mixing and reaction after the upconversion luminescence biosensor and the sample to be tested enter the arc-shaped channel; a separation channel connected to the outlet of the arc-shaped channel for magnetic separation of the upconversion luminescence biosensor after the reaction is completed; and a detection cell connected to the outlet of the separation channel for completing luminescence-enhanced quantitative detection of EDCs.

The application discloses a kind of silicon quantum dot enhanced Raman's optical microcavity laser sensing method and system.The method comprises: reference light and excitation light are coupled to optical microcavity, and the Raman laser of optical microcavity is excited by excitation light;First sharp peak signal and second sharp peak signal are obtained by the interference of two split Raman lasers with reference light respectively, and third sharp peak signal is obtained by the mutual interference between two split Raman lasers;The line width and intensity of third sharp peak signal are observed by adjusting the intensity difference of first sharp peak signal and second sharp peak signal, the line width and intensity of third sharp peak signal are optimized, and the intensity difference of optimized first sharp peak signal and second sharp peak signal is determined;According to the third sharp peak signal after optimization, determine the information of the substance to be measured.The problems of traditional sensing system in signal-to-noise ratio, detection accuracy and detection limit are solved by the embodiment of the application, the detection accuracy is optimized, the signal-to-noise ratio is improved, and the detection limit is reduced.

The utility model discloses a kind of online monitoring device for switchgear insulation state multipoint detection, including host computer and sampling pipeline, host computer includes shell, circuit board, vacuum pump and sensor module, circuit board is electrically connected with vacuum pump and sensor module and is all arranged in shell, electromagnetic valve control interface, gas enrichment module control interface, 4G antenna, touch screen and button are arranged on shell lateral wall with circuit board electrically connected, the air inlet end of vacuum pump is communicated with air inlet by sensor module, the air outlet end of vacuum pump is communicated with exhaust port;Sampling pipeline includes gas enrichment module, plastic hose and electromagnetic valve;The application is switched automatically by gas path stop valve switch, realizes switchgear internal multipoint gas collection and measurement, different kinds of gas sensors are used to carry out online monitoring to the volatile organic or inorganic gas generated, after adsorption concentration to gas by gas enrichment module, desorption detection is carried out, improve the sensitivity and detection limit of gas.