210results about How to "Achieving High Sensitivity Detection" patented technology

A method of using picosecond scan camera to simultaneously obtain fluorescent light spectrum and fluorescent lifetime of sample includes focusing blue violet light emitted by laser on sample by objective to excite sample single photon, collecting fluorescent from sample then splitting it and focusing it to be image on photoelectric cathode of picosecond scan camera, setting dispersion direction of fluorescent to be the same as slit direction of said camera but to be vertical to scan direction in order to measure out fluorescent lifetime of different light spectrum simultaneously under coaction of scan circuit and image intensifier deflection system.

The invention discloses a three-dimensional graphene/carbon nanotube network flexible multifunctional strain sensor preparation method. According to the invention, the three-dimensional network of three-dimensional graphene and a one-dimensional carbon nanotube grows through two-step chemical vapor deposition; and the three-dimensional network and an elastic polymer as a flexible substrate are solidified and combined to acquire a flexible wearable multifunctional electronic strain sensor based on the three-dimensional network of the graphene and the carbon nanotube. According to the invention, the electronic strain sensor breaks the limitation relationship between the strainability and the sensitivity of the strain sensor, has an excellent electronic strain sensing performance and the function of a micro heater, realizes high sensitivity detection of human physiological signals and physical activities, shows excellent electronic skin simulation capabilities and a micro heating source application performance, has the advantage of simple process, and can be widely used in many fields such as clinical diagnosis, health monitoring, a robot, an electronic screen, electronic skin, a flexible micro heater and intelligent home.

The invention discloses a ZnO-Ag surface enhanced Raman scattering substrate and detection of organic pollutants with the substrate. The preparation method for the substrate comprises the following steps: the first step, ITO conductive glass is subjected to ultrasonic cleaning with acetone, alcohol and deionized water one by one and dried in the air; the second step, organic additives are added in a zinc nitrate solution, a first mixed liquid is formed, after the first mixed liquid is stirred for 30 min, an ammonia-water solution with a mass fraction of 25% is dropwisely added in the first mixed liquid, a second mixed liquid is formed, the processed ITO conductive glass from the first step is soaked in the second mixed liquid, after the water bath is at a constant temperature, the ITO conductive glass is placed in a baking box and baked for 60-100 min, a white and uniform ZnO layer is formed on the surface of the ITO conductive glass; the third step, Ag nanoparticles are deposited on the prepared ZnO nanolayer from the second step, and a ZnO-Ag surface enhanced Raman scattering substrate is obtained. The preparation method is simple. The prepared substrate has high sensitivity and good stability and can be used repeatedly.

The invention provides an MOX@MOFs (metal oxide-metal-organic frameworks) nanometer core-shell structure one-dimensional array film which is characterized in that the film thickness is 2 to 4 micrometers, and the film is formed by a one-dimensional MOX@MOFs core-shell structure, wherein the diameter of a core MOX nanowire is 50 to 100nm, the thickness of a shell MOFs can be adjusted between 1nm to 200nm, metal nodes and organic chains of the MOFs can be adjusted. A typical preparation method comprises the steps of setting an MOX face of a ZnO one-dimensional array film downwards, adding into a mixed solution of water in which zinc salt, cobalt salt and organic ligands are dissolved and DMF, sealing a reaction still, then heating for reacting, after reacting, washing the surface of a compound array film, and drying the film in the air. The MOX@MOFs core-shell structure one-dimensional array film provided by the invention has excellent gas-sensitive property, not only can humidity interference be selectively eliminated, but also the working temperature can be reduced and the sensitivity can be improved through a Co catalysis. Meanwhile, the film also has the advantages that the method is simple, and the cost is low.

The invention relates to a photoelectrochemical sensor, and preparation and application thereof. A preparation method for the photoelectrochemical sensor comprises the following steps: S1, pretreating ITO electro-conductive glass; S2, adding TiO2 nanoparticles onto the ITO electro-conductive glass drop by drop to prepare an ITO/TiO2 electrode; S3, soaking the electrode in a carbon quantum dot solution for 10 h so as to obtain an ITO/TiO2/CODs electrode; S4, adding chitosan onto the electrode drop by drop so as to obtain an ITO/TiO2/CODs/CS electrode; S5, adding a glutaraldehyde solution onto the electrode drop by drop; and S6, dropwise adding thrombin aptamer drops, carrying out a reaction at 4 DEG C under a wet condition for 10 to 15 h, continuing adding bovine serum albumin onto the electrode drop by drop after leaching and blow-drying, and carrying out leaching and blow-drying again. The prepared photoelectrochemical sensor can be used for detection of thrombin. According to the invention, the carbon quantum dots with a wide visible light absorption range, good luminosity and high-efficiency electron injection capability are used as a photosensitizer for titanium dioxide, so the obtained composite structure has good response to photoelectric current under visible light. The prepared photoelectrochemical sensor has the advantages of simple operation, low cost, environment friendliness, high sensitivity and good selectivity.

The invention discloses a zirconium-base metal organic frame composite material and a preparing method and application thereof. By controlling experiment conditions, a UiO-66-NH2 metal organic frame material with the grain diameter of 100 nm is obtained, and serves as a loading matrix, a signal molecule tri-(2,2'-dipyridyl) ruthenium dichloride is embedded in a pore way structure regularly and evenly distributed, a Ru-UiO-66-NH2 material is obtained, loading of silver nanoparticles is conducted through the high specific surface area of the Ru-UiO-66-NH2 material, and the obtained Ru-UiO-66-NH2material is applied to detection of small-molecule hydrogen peroxide with the electrogenerated chemiluminescence detection technology. Through the method, interference of background signals can be avoided, optical signals are stable, and the sensitivity is high.

The invention relates to a laser desorption ionization mass spectra, in particular to application of diamond-like carbon film used as matrix in the laser desorption ionization mass spectra; the surface of the diamond-like carbon film is used as an assisting matrix of laser desorption ionization flying time mass spectra, the diamond-like carbon film has high desorption ionization efficiency to compounds with low molecular weight and can not generate background interference of matrix molecules, so as to realize high-efficiency and rapid detection to the compounds with low molecular weight; the laser desorption ionization flying time mass spectra which adopts the diamond-like carbon film as the assisting matrix is a new desorption ionization method without adding any organic matrix, so as toprovide a general, high-efficiency and rapid detection method for the compounds with low molecular weight such as natural products and ecological metabolites, promote the development of analysis of compounds with low molecular weight by the laser desorption ionization flying time mass spectra technology and find new field for the application of the diamond-like carbon film material.

The invention discloses a method for rapid detection of the residual mount of sulfanilamide in food. The method comprises the following steps: firstly enabling the sulfanilamide and fluorescamine to perform derivation reaction, further enriching derivative products by using cloud point extraction, adding a sample enrichment and a standard plate prepared from a sulfanilamide standard product on a thin layer silica gel plate, comparing the fluorescence intensities of the two under an ultraviolet lamp to judge the concentration range of the fluorescamine in a sample, and determining the residual amount of the sulfanilamide in the food, wherein a detection limit of the method is 0.08 micron g/mL. The method disclosed by the invention has the advantages of simplicity in operation, small using amount of organic solvent, high detection sensitivity, short detection time, strong specificity and capability of realizing effective separation from interfering substances, is a simple, convenient, fast and accurate analytical method, does not need large-scale instruments, only needs to configure small-scale instruments and equipment, and further has extensive application prospects.

The invention provides a biosensor for detecting streptomycin based on an aptamer. The biosensor comprises a gold electrode, wherein an MB capture probe layer, HAP and an ssDNA layer are sequentially modified on the gold electrode. The invention also provides a preparation method of the biosensor. Based on specific recognition of the aptamer and the target, the sensor has the advantages of high detection speed, low detection limit, high specificity and the like, the defects of the conventional streptomycin detection method can be overcome, and rapid and accurate quantitative determination is realized.

The invention discloses a method for detecting amoxicillin residual quantity in milk and meat products. The method includes the following steps: preparing amoxicillin standard aqueous solution; adding a nonionic surfactant; reacting the obtained solution with quinone or alizarin to get a charge transfer system; determining the wavelength scanning range of fluorescence or ultraviolet; further calculating the linear range, working curve and other parameters of the standard solution; processing the sample to be detected by corresponding charge transfer reaction; determining reaction parameters under ultraviolet or fluorescence; and calculating to obtain the amoxicillin residue quantity. The technology further enhances the value of fluorescence intensity or UV absorption by utilizing the sensitizing effect of non-ionic surfactants, thus meets the low-residue testing requirement; simultaneously improves the system stability significantly, makes up the disadvantage of poor detection stability of fluorescence in the earlier application, and is more feasible in the actual detection.

The invention discloses a thrombin detection method based on a splitter adapter and a water-soluble conjugated polymer. According to the method, a super-molecular detection platform based on a water-soluble conjugated polymer/nucleic acid adapter is designed by virtue of the sensitivity of the water-soluble polymer on a comformational change of a deoxyribonucleic acid (DNA) chain and according to the characteristics that the nucleic acid adapter has specific binding ability and the like. Two sequences cannot form a G-four-chain structure when thrombin does not exist in a solution or other nonspecific proteins exist in the solution, the distance from a compound to the polymer is small, and thus effective energy transfer between the compound and the polymer can be realized; when the thrombin exists in the solution, the thrombin induces the two sequences to form the G-four-chain structure, and the distance between the compound and the polymer is increased, so that effective energy transfer cannot be carried out. The method disclosed by the invention is simple, convenient and fast, is high in sensitivity and selectivity, and has important significance in the aspect of thrombin detection.

The invention discloses a construction method and an application of an electrochemical Faraday cage immunosensor for detecting the activity of histone acetyltransferase. The construction method comprises the following steps: (1) preparing peptide/Au: respectively taking acetyltransferase p300, polypeptide and acetyl-CoA, fully mixing the taken substances in PBS (0.1 M, pH 7.0), incubating the obtained solution in a constant-temperature water bath, taking and dropwise applying a catalytic reaction to the surface of a gold electrode, and incubating the gold electrode in a 4 DEG C refrigerator; (2) preparing MB&AuNPs@GO-Ab: mixing HAuCl4 and CTAB with water, adding ascorbic acid to the obtained reaction mixture, adding NaOH to obtain CTAB covered AuNPs, centrifuging and purifying the CTAB covered AuNPs, dispersing the purified CTAB covered AuNPs in an equal amount of water, adding GO to the obtained solution, performing ultrasonic dispersion, standing the dispersed solution for later use,adding an acetyl antibody, performing incubation, adding MB, and performing vibration and uniform mixing; and (3) producing the electrochemical Faraday cage immunosensor: taking and dropwise applyingthe MB&AuNPs@GO-Ab to the surface of the peptide/Au, performing incubation at room temperature, and placing the produced sensor in the PBS (0.1 M, pH 7.0) to carry out electrochemical SWV test.

The invention relates to an ultrasonic phased array detection system for a transitional circular arc inside a cavity. The system comprises an ultrasonic phased array detector, a detection probe and a positioning device. The system is characterized in that a probe propelling device consisting of an auxiliary operating frame, a balancing weight, a probe clamping block, a fine steel wire and the like is designed. The ultrasonic phased array detection system for the transitional circular arc inside the cavity provided by the invention has the advantages of: 1, ensuring that the centre of curvature of an arc-shaped wafer of the detection probe is concentric with the circular arc detected so that an ultrasonic wave is vertically incident to corner parts of the circular arc detected so as to realize detection with high sensitivity of all parts of the circular arc; 2, ensuring that the probe operates stably in the cavity structure clings to the side wall of the circular arc detected; 3, ensuring coupling of detection by forming a sealed water cavity between the detection wafer of the probe and the circular arc detected through the detection probe and the front and back clamping blocks; and 4, precisely positioning the movement position of the detection probe through the probe positioning device so as to position the defect horizontal position precisely.

The invention relates to a micro device for performing on-line enrichment, elution, fluorescence labeling and detection on protein, and in particular provides a rapid protein analysis and detection device based on whole microfluidic chip closing system. The device is composed of a micro fluidic controlling system, a miniature laser induced fluorescence detection system, a microfluidic chip, an injection valve, a connecting pipeline, an interface and a data acquisition and processing part. A protein sample is enriched by an enriching column in a chip passage, is subjected to on-line fluorescence labeling operation and elution operation at the same time, and is induced by laser to be subjected to fluorescence detection. The rapid protein analysis and detection device has the advantages that the sample pre-processing process, fluorescence labeling and detection are integrated so as to enable cumbersome steps of an off-line analysis method to be omitted, the sample processing time is greatly shortened and the high sensitivity detection is achieved; the whole device is small in size and low in energy consumption; the microfluidic chip and a micro injection pump are connected through the interface with a special design; a whole fluid system runs in the closing system, the detection requirement under a special condition (such as non-gravity state) can be met. Thereby, the rapid protein analysis and detection device has the very good practical application value.

The invention provides a molecular imprinting microfluidics sensor based on a double-annular-fiber-core optical fiber and the double-annular-fiber-core optical fiber. The double-annular-fiber-core optical fiber comprises two annular fiber cores and a microfluid channel [4], wherein the first annular fiber core [1] is positioned on the inner wall of an annular wrapping layer [2]; the second fiber core [3] is positioned inside the annular wrapping layer [2]; the microfluid channel [4] is used as a sample sensing field; a molecular imprinting sensitive layer [8] is arranged on the inner surface of the annular fiber core [1]; micro holes [6] and [7] are formed in the surface of the double-annular-fiber-core optical fiber; two micro holes are positioned in one same side of the double-annular-fiber-core optical fiber; the double-annular-fiber-core optical fiber [5] is connected with an incident optical fiber [11] and an emergent optical fiber [12] through optical fiber pull conical points [9] and [10]; the incident optical fiber [11] is connected with an optical fiber coupler [16]; the optical fiber coupler [16] is connected with a light source [17]; the emergent optical fiber [12] is connected with a spectrometer [18]. The sensor is simple in structure and small in size, and can achieve high-selectivity on-line microfluidics detection.

The invention relates to a dialysis device and silicon nanowire field-effect tube combined biosensor. The dialysis device and silicon nanowire field-effect tube combined biosensor comprises a dialysisdevice, a silicon nanowire field-effect tube and a signal output computer, wherein the dialysis device is communicated with the silicon nanowire field-effect tube through a thin silica gel flexible pipe; and the silicon nanowire field-effect tube transmits a signal to the signal output computer through a probe. The serum desalting dialysis device and the silicon nanowire field-effect tube are connected into the same pipeline; the dialysis device is used as a filter; the field-effect tube having a double gate structure with a semiconductor silicon nanowire as a channel is used as a signal converter; an antibody corresponding to a tumor marker is used as a biological sensitive element; and therefore, the immediate, label-free and high-sensitivity detection of the serum tumor marker is realized.

The invention relates to the technical field of the biosensor, and especially relates to a biosensor for detecting ATP by bringing Apt-1 and Apt-2 closer by ATP and using branch HCR amplification signal. A CP-SH layer, an AP layer, a HP1-HP2-HP3-HP4 layer and a [Ru(NH3)6]3+ layer are orderly modified on an electrode; the preparation method comprises the following steps: pre-treating the electrode,modifying the CP-SH layer to an electrode surface; modifying the AP layer to the electrode surface, and modifying the HP1-HP2-HP3-HP4 layer to the electrode surface, and modifying the[Ru(NH3)6]3+ layer to the electrode surface. The high specificity detection of the target object ATP is realized by utilizing the specificity identification of the aptamer; by utilizing the effect of bring two aptamers closer by the ATP, the cyclic utilization of the target object is realized, and the effect of the first-step signal amplification is achieved. And a signal continuous enhancement effect is realizedby utilizing branch HCR.

The invention relates to a wavelength modulation absorption spectrum absorption optical path and gas concentration synchronous inversion method. The method comprises the following steps: (1) acquiringan absorption signal It and a background signal It, 0; (2) obtaining a first harmonic phase baseline value and a first harmonic phase angle differential signal delta theta 1f-0 of which background signals are deducted by adopting a quadrature demodulation method; (3) solving an absorption optical path Labs by adopting a formula; and (4) performing least square method linear fitting on the differential phase angle delta theta 1f-0 of which the background is deducted by adopting the following formula so as to obtain the concentration of to-be-detected gas, according to the present invention, with the method, the defects in the prior art can be overcome, the absorption optical path and the gas concentration can be rapidly and synchronously inverted, the high-sensitivity absorption optical path and the gas concentration detection can be achieved, and the method is especially suitable for the gas detection environment with the obvious noise such as remote measurement and the like.

The invention relates to a terahertz metamaterial chip for cell invasion and migration unmarked detection. A cell culture chamber, a porous film and a metamaterial chip layer are integrated, and by alocally enhanced electric field of the terahertz metamaterial in vertical micron distribution, in-situ unmarked detection of quantity of cells penetrating the porous film is performed to assess movement behaviors such as cell invasion and migration. A whole device is simple in structure, convenient to assemble, small in size, easy to integrate and reusable.

The invention discloses a method for detecting trace iron ions at high sensitivity, which comprises the steps of: searching a proper medium condition of diaminomaleonitrile (DAMN); measuring fluorescence intensities of a coordination compound, the coordination compound and a medium, and the coordination compound and the medium and metal ions; determining hypersensitivity or quenching effect generated by metal ions to the fluorescence of the coordination compound; measuring a linear relation between the concentration of the metal ions and a quenching value; and measuring the content of the metal ions in food. By using characteristic of quenching generated by the iron ions to the fluorescence of the DAMN and the linear relation formed between the fluorescence quenching value (delta F) and the concentration of the iron ions, the method is further used for measuring the content of iron in foods of infant rice flour, milk powder and the like, wherein the detection limit of the iron is 1.5 mu g.L<-1>, and the relative standard deviation is 0.17 percent. Compared with the prior art, the method has the advantages of good selectivity, high sensitivity, simple and convenient use, and the like.