120 results about "Specific fluorescence" patented technology

The invention provides a sample pretreatment automation method for flow cytometry, and belongs to the technical field of sample pretreatment for flow cytometry. A biological sample to be detected is collected and placed in a collection tube containing an EDTA-K2 anticoagulant for pretreatment; an automatic pipetting system is used for carrying out incubation reaction on an anticoagulant whole blood sample and an intelligent matching fluorescence labeling antibody mixed solution, and a double-layer game optimization verification system is used for verifying the rationality of an antibody adding proportion and reaction condition parameters; carrying out fluorescence characteristic readability index prediction on the incubated cell suspension by adopting an intelligent dilution parameter regulator model, dynamically adjusting hemolysis parameters and suspension conditions, and adding 1 * hemolysin working solution by using an automatic liquid adding device to carry out hemolysis treatment so as to finish pretreatment; the technical problems that in the pretreatment process of flow cytometry detection samples, parameters are often based on artificial experience, and the reproducibility and standardization degree of detection results are insufficient are solved.

The invention discloses a staphylococcus aureus biosensor based on a nucleic acid aptamer and a preparation method of the staphylococcus aureus biosensor. Three fluorine atoms (F) are introduced into the 5'end, the 3 'end and the middle position of an aptamer 2' F3-(5 '3'm DNA) sequence (SEQ ID NO: 1) for modification, so that the binding force of the aptamer and graphene is remarkably enhanced, the signal stability and the anti-interference capability of the biosensor are remarkably improved, non-specific fluorescence leakage can be effectively blocked, and reliable guarantee is provided for complex sample detection. According to the present invention, with the cooperation of the graphene oxide quenching substrate, the high-sensitivity detection of the staphylococcus aureus is achieved, the detection limit of the sensor within 5 min can achieve 5 cells / mL, the sensitivity is high, the specificity on the complex sample is more than 95.4%, and the sensor is suitable for the food safety rapid screening and the clinical diagnosis.

The invention provides an optical detection method and system.The method comprises the steps that fluorescence microscopic imaging is conducted on a marked imaging target multiple times, multiple frames of first imaging images are obtained, the marked imaging target is an imaging target marked by a blend, the blend comprises specific fluorescence probe molecules, and the specific fluorescence probe molecules are used for detecting the specific fluorescence probe molecules; the specific fluorescent probe molecules are determined from fluorescent probe molecules according to preparation steps corresponding to the imaging target; super-resolution reconstruction is carried out on the multiple frames of first imaging images, a second imaging image is obtained, and the second imaging image is used for obtaining a detection result of the preparation step. The detection precision can be improved while the detection resolution is improved.

The invention discloses a regenerated polypropylene composite material as well as a preparation method and application thereof. The regenerated polypropylene composite material comprises the following components in parts by weight: 50-90 parts of regenerated polypropylene resin; 5-30 parts of polypropylene resin B; 0.1 to 0.8 part of a rheological agent; wherein the EPR content in the polypropylene resin B is not less than 28wt%; the one-minute half-life period temperature of the rheological agent is not higher than 210 DEG C; the fluorescence intensity of the regenerated polypropylene resin at 380 nm to 420 nm is 4,000 to 6,500. The rheological agent with the one-minute half-life period temperature not higher than 210 DEG C and the polypropylene resin B with the EPR content not lower than 28 wt% are added into the regenerated polypropylene resin with the specific fluorescence intensity for compounding, the paint adhesive force of the regenerated polypropylene composite material can be effectively improved, and the mechanical property is good.

The invention discloses a confocal laser microscope detection method for micro-plastic surface biofilm components and biomass, and belongs to the field of micro-plastic pollution monitoring. The method comprises the following steps: carrying out stratified sampling and polymer component identification on micro-plastic in an environmental water body; the method comprises the following steps: marking algae, blue-green algae, bacteria and extracellular polymeric substances in a biological membrane through specific fluorescent staining, carrying out high-resolution three-dimensional imaging by utilizing a confocal laser microscope, and realizing batch quantitative analysis of each component of the biological membrane by adopting ImageJ software. The technical problems that an existing detection method is insufficient in parameter dimension, evaluation result deviation is caused only based on partial component quantification, and the influence of the overall structure of the biological membrane on the micro-plastic migration behavior cannot be truly reflected are solved. According to the method, the biomass and spatial distribution of each component of the biological membrane can be comprehensively and accurately quantified, the accuracy of analyzing the vertical migration mechanism of the micro-plastic is improved, and multi-dimensional data support is provided for ecological risk assessment.

The invention belongs to the technical field of biology, and particularly discloses a system for detecting HIV RNA, a fluorescent biosensor and preparation and application of the fluorescent biosensor. The system comprises red blood cells, a first report chain, a second report chain, crRNA, Cas12a and a DNA hairpin probe H1. On the basis of the system, a fluid membrane-red blood cell confinement Cas12a can be constructed, and a simple, sensitive and specific fluorescence detection sensing strategy of virus RNA such as HIV RNA is developed, so that the problems of low reaction efficiency, complex reaction steps and the like of an HIV RNA detection method based on CRISPR-Cas12a in the prior art are solved.

The application discloses a kind of biological sensor of nucleic acid aptamer-based paratyphoid A salmonella and preparation method thereof, it is introduced 3 fluorine atoms (F) modification in the 5' end, 3' end and intermediate position of aptamer 2'F3-(5'3'mDNA) sequence (SEQ ID NO:1), significantly enhance the binding force of aptamer and graphene, significantly improve the signal stability and anti-interference ability of biosensor, and can effectively block non-specific fluorescence leakage, provide reliability guarantee for complex sample detection.The application is matched with graphene oxide quenching substrate, realizes the high sensitivity detection of paratyphoid A salmonella, the detection limit of the sensor reaches 10 cells / mL within 5 min, the specificity to complex sample is >93.4%, and it is suitable for food safety rapid screening and clinical diagnosis.

An image sensor and a forming method therefor. The method comprises: acquiring a substrate, having a first surface and a second surface which are opposite to each other, wherein the substrate is provided with a plurality of photoelectric sensing areas, and the first surface exposes the surfaces of the photoelectric sensing areas; forming a filter film on the photoelectric sensing areas, wherein the filter film allows for passing of an optical signal having a wavelength greater than a preset wavelength; and forming a first protective layer on the surface of the filter film. On one hand, an optical signal of a specific fluorescence band can be obtained by configuring the filter film, so that a fluorescence imaging experiment can be performed subsequently by means of such fluorescence band, thereby realizing lens-free imaging of a fluorescence signal, and simplifying the fluorescence microscopic detection process; on the other hand, the filter film is formed on the photoelectric sensing areas having a flat surface, so that the thicknesses of all positions of the filter film are uniform, thereby reducing the possibility of diffuse reflection and scattering of the fluorescence signal on the surface of the filter film caused by non-uniform thickness of the filter film, and ensuring the reliability of the fluorescence microscopic detection result.

To provide a detection reagent hardly causing noise due to generation of nonspecific fluorescence, and capable of detecting sialidase with higher accuracy.SOLUTION: The present invention relates to a compound represented by formula (I) or a salt thereof, or a solvate thereof. In the formula (I), R1 represents a halogen atom, and R2 represents an alkyl group having 5 to 11 carbon atoms or a hydrocarbyl group having 5 to 11 carbon atoms and having one or more unsaturated bonds. ] SELECTED DRAWING: None

The invention relates to a labeling technique formed by using molecular organic crystals having non-reproducible random position, shape, color and orientation, as well as specific fluorescence emission and physicochemical properties.

The invention discloses a preparation method and application of aerogel for detecting and adsorbing aluminum ions, and belongs to the technical field of sewage treatment. According to the method, a halloysite nanotube is taken as a matrix, and the HNT-KC probe with specific fluorescence response to aluminum ions is synthesized through silanization, acylating chlorination and gradual reaction with a coumarin derivative and furohydrazide; meanwhile, preparing aldehyde-terminated polyethylene glycol as a cross-linking agent; finally, the probe, a chitosan solution and an aldehyde-terminated polyethylene glycol solution are subjected to co-gelation through a Schiff base reaction, and the composite aerogel is prepared through dehydration aging and freeze drying. The aerogel integrates fluorescence detection and adsorption removal functions, has the advantages of high specific surface area, porous structure, high sensitivity, strong selectivity and good stability, can realize rapid detection and efficient removal of aluminum ions in a water body, is green in raw materials and simple in process, and has a wide application prospect in the field of water treatment.

The invention belongs to the technical field of immunodiagnosis, and relates to a detection card for quantitatively detecting human total IgE antibodies, which comprises a card shell and a test strip, and the test strip is arranged in the card shell; the test strip comprises a sample pad, a combination pad, a reaction film and an absorption pad which are arranged on a bottom plate, wherein an animal anti-human IgE monoclonal antibody marked by lanthanide fluorescent microspheres is arranged on the combination pad; a detection line coated with an animal anti-human IgE polyclonal antibody and a quality control line coated with an animal IgG antibody are arranged on the reaction film. The invention further provides a preparation method, a kit and application of the detection card for quantitatively detecting the human total IgE antibody. The method can effectively eliminate the interference of non-specific fluorescence, greatly improves the analysis sensitivity, and is simple and convenient to operate and low in cost.

The application discloses a preparation method and a quantitative detection method of a DPA functionalized UIO-66-based ratio type zinc ion fluorescent probe, and belongs to the technical field of environmental monitoring and fluorescent sensing materials. The application takes UIO-66(Zr) metal organic framework as a porous carrier, in-situ encapsulates nitrogen-doped carbon dots as a stable reference fluorescent unit, constructs zinc ion specific recognition sites by grafting dipyrromethane amine chelating groups on the framework surface through amidation reaction, and prepares a double-emission ratio type fluorescent probe; and the quantitative detection is realized based on the fluorescence intensity ratio value of the 440nm reference peak and the 530nm response peak. The application improves the anti-interference ability through the ratio type signal and the specific chelation double mechanism, the detection limit of the method is as low as 0.12 micromole / L, the interference rates of 10 times of concentration of coexisting metal ions are all lower than 5%, and the application is suitable for accurate and rapid detection of trace zinc ions in complex water quality such as industrial wastewater and surface water.

The invention relates to the technical field of environmental monitoring, and discloses a preparation method of a multifunctional fluorescent material for detecting pollutants in water, and the preparation method comprises the following steps: carrying out hydrothermal reaction on carbon aerogel, croconic acid, melamine and water to obtain a hydrothermal carbon solution and modified carbon aerogel; reacting the hydrothermal carbon solution, double-stranded DNA, magnesium salt and a buffer solution to obtain an active solution; dipping the modified carbon aerogel into the active liquid, and carrying out ultrasonic reaction to obtain the multifunctional fluorescent material. Under the ultraviolet condition, the fluorescent probe can be combined with copper ions and tetracycline to generate specific fluorescence characteristics, and can be used for detecting copper ions and tetracycline in water, so that the convenience and specificity of detection are improved, and the detection time is shortened. The modified carbon aerogel can effectively improve the enrichment of copper ions and tetracycline in water by the material and improve the detection sensitivity and accuracy.

The invention discloses a rolling circle amplification (RCA) molecular beacon based on DNA synthesized silver nanoclusters (AgNCs / DNA) and application of the rolling circle amplification (RCA) molecular beacon in DNA and RNA virus detection. According to the invention, a padlock template probe PlP with a specific secondary structure is used for carrying out two-enzyme one-step method RCA to generate single-stranded DNA containing a G-rich sequence tandem repeat element. Then H2O2 is added to eliminate the influence of residual dithiothreitol DTT in the RCA reaction, and then AgNCs / DT-GSP-t4 is used as a signal probe to generate a specific fluorescence enhancement signal for a to-be-detected target under the action of a G-rich proximity fluorescence enhancement effect. The RCA reaction does not need primer mediation, so that PlP design and RCA operation steps are simplified; meanwhile, the single-PlP or double-PlP probe is combined with the fluorescent molecular beacon, so that single-base mismatch at a PlP connection point can be recognized, and the probe has the advantage of high specificity.

The invention discloses a recombinant plasmid, a recombinant strain, recombinant phycocyanin and application of the recombinant plasmid, the recombinant strain and the recombinant phycocyanin in mercury ion detection. The invention further discloses a dual-mode mercury ion biosensor based on the thermal-stability recombinant phycocyanin and a preparation method and application of the dual-mode mercury ion biosensor. The biosensor based on the recombinant phycocyanin has specific fluorescence response to trace mercury ions. The recombinant phycocyanin pigment binding rate is higher than that of all reported recombinant phycocyanin, great Stokes shift (288 nm) is shown, the mercury ion selectivity is high, the thermal stability is good, the prepared biosensor shows the characteristics of dual-mode output and ultra-sensitive sensing, the detection limit under a fluorescence-based mode is 2.94 nM, and the biosensor has good application prospects. And the detection limit is 1.87 nM in a colorimetric mode based on fluorescence. The protein-based sensor is obtained from escherichia coli, is simple and convenient, supports in-situ monitoring of a smart phone, and is low in cost, excellent in performance and free of any toxicity.

The present invention belongs to the field of liquid biopsy, and particularly relates to a method for visualizing the recognition profile of rare single cells, comprising the following steps: specifically staining the cell membranes of circulating tumor cells; adding a fluorescence enhancement reagent, which is an organic phase solution of a surfactant or an organic alcohol; performing microscopic imaging; converting the microscopic image into a digital photograph, and amplifying the digital signal in the digital photograph to obtain a visualized cell contour map. The present invention uses a surfactant or an organic alcohol to enhance the specific fluorescence on the cell surface, thereby improving the signal-to-noise ratio of the surface fluorescence signal; by using digital signal amplification technology, the visualization of the specific recognition profile of single cells is achieved, avoiding signal loss of the imaged cells; based on the fluorescence-visualized cell contour, the accuracy of capturing CTC counting and size estimation can be realized.

The invention discloses a Au@ZnO / Pt nanocomposite material and a preparation method thereof and an application thereof in detecting tetracycline antibiotics, wherein the nanocomposite material is a core-shell structure, wherein the shell layer is zinc oxide, and the core layer is gold nanoparticles, and platinum nanoparticles are loaded on the shell layer. The zinc ions in the Au@ZnO / Pt nanocomposite material of the present invention can coordinate with tetracycline to produce specific fluorescence enhancement, and the oxidase-like activity of the nanocomposite material can catalyze and oxidize TMB to ox-TMB, thereby establishing a fluorescence analysis method / colorimetric analysis method of tetracycline, all with extremely low detection limits. The composite material is used for tetracycline antibiotic detection and belongs to a fluorescence enhancement probe material, and relative to a fluorescence quenching material, has good specific selection, anti-interference and high sensitivity, and therefore the nanocomposite material is used to detect tetracycline antibiotics, and rapid, efficient, sensitive and simple detection can be achieved.

This invention discloses a Staphylococcus aureus biosensor based on a nucleic acid aptamer and its preparation method. By introducing three fluorine atoms (F) at the 5', 3', and middle positions of the aptamer's 2'F3- (5'3' mDNA) sequence (SEQ ID NO:1), the binding force between the aptamer and graphene is significantly enhanced, significantly improving the signal stability and anti-interference ability of the biosensor. Furthermore, it effectively blocks non-specific fluorescence leakage, providing reliable assurance for the detection of complex samples. This invention, combined with a graphene oxide-quenched substrate, achieves highly sensitive detection of Staphylococcus aureus. The sensor achieves a detection limit of 5 cells / mL within 5 minutes, exhibiting high sensitivity and a specificity >95.4% for complex samples, making it suitable for rapid food safety screening and clinical diagnosis.

The invention discloses a reagent for reducing autofluorescence, which comprises copper sulfate, ammonium chloride and a solvent, and the solvent is water. The invention further discloses a method for preparing the animal tissue paraffin slice. According to the method, cell membrane fluorescence labeling can be maintained while good animal tissue morphology is maintained, non-specific fluorescence is reduced, the signal-to-noise ratio of fluorescence imaging is increased, operation is easy and convenient, reagents are low in cost and easy to obtain, and the imaging quality is effectively improved.

The invention provides a double-lock type viroid fluorescent nanoprobe for monitoring a virus infection process, and a preparation method and application of the double-lock type viroid fluorescent nanoprobe. The probe is composed of a Japanese encephalitis virus envelope E protein modified polyamidoamine dendrimer, and the polymer is loaded with a vRNA and depurine / depyrimidine endonuclease 1 (APE1) dual activated molecular beacon. The probe can penetrate through a blood brain barrier and enter virus-infected cells to release molecular beacons complementary with vRNA, and the molecular beacons are selectively split by APE1, so that specific fluorescence signal amplification in virus-infected lesions is realized. The double-activation strategy greatly improves the spatial accuracy and sensitivity of virus infection focus imaging. The invention provides a feasible method for monitoring the in-vivo virus infection level in real time and evaluating the effectiveness of antiviral drugs.

The application belongs to the field of microbial molecule detection, and discloses a multiple qPCR kit and method for simultaneously detecting multiple listeria based on new molecular targets. The application designs corresponding primers and probes based on specific gene fragments of each listeria obtained by genomics mining, establishes a multiple qPCR method, and assembles the method into a portable kit. The multiple qPCR primer probe set of the application has high specificity, and only the six target bacteria of Listeria monocytogenes, Listeria innocua, Listeria ivanovii, Listeria welshimeri, Listeria seeligeri and Listeria grayi appear fluorescence signals in the specific fluorescence signal channel, so that the detection result is more accurate. The multiple qPCR kit of the application can complete sample detection within 14 hours, wherein the whole qPCR process only needs about 1 hour, the detection efficiency is high, the detection cost is low, and the kit is particularly suitable for large-scale sample investigation and actual detection, and the detection sensitivity can be as low as 1.0-11.1 CFU / Test.

The invention belongs to the field of analytical chemistry, and particularly relates to preparation and application of a fluorescent probe PCH for detecting HSO3 <-> based on hemicyanine. Experimental results show that the fluorescent probe PCH shows specific fluorescent response to HSO3 <->, and is high in selectivity and strong in anti-interference capability. In the HSO3 <-> detection process, the color of the solution is changed from purple to yellow, and visual detection can be carried out. Compared with the prior art, the method has the advantages that the reaction process is mild, the probe performance is excellent, and the method has a wide application prospect in the aspect of HSO3 <-> detection.

The invention discloses a method for obtaining a single B cell and screening an antibody, and relates to the technical field of monoclonal antibody development. According to the invention, B cells are enriched through a magnetic bead anion selection method, and target B cells are screened by identifying a specific fluorescence signal mode. The method provided by the invention is helpful for improving the enrichment efficiency of the target B cells, reducing the enrichment cost, increasing the proportion of the positive cells after enrichment, also helpful for screening high-affinity antibodies, and improving the efficiency of antibody discovery.

The present application relates to a kind of zinc-based coordination polymer and film preparation method and application fluorescent detection of sparteine.Polymer is three-dimensional zinc metal organic framework material, the frame is connected by binuclear zinc and organic ligand to have one-dimensional pore, chemical formula is {NH2(CH3)2·[Zn (TDA)]·DMF·3C2H5OH} n};With fluorescence emission peak at 400nm.It is prepared by hydrothermal reaction by zinc iodide and 4,4'‑(1H‑1,2,4‑triazole‑3,5‑diyl) dibenzoic acid in DMF and ethanol mixed solvent, add acetic acid as regulator.The zinc-based coordination polymer and film prepared by the present application have specific fluorescence recognition function, can quickly and conveniently detect sparteine in water and other solutions, the detection limit is as low as 5.26×10 ‑6 M, high sensitivity and can be recycled.And preparation process is simple, application portable, not dependent on expensive equipment.

The invention discloses special paper based on a multi-layer anti-counterfeiting function and a preparation method thereof, and belongs to the technical field of paper anti-counterfeiting. The special paper sequentially comprises a base paper layer, a fluorescent color fiber coating layer, a dielectric film sizing layer and a three-dimensional anti-counterfeiting transparent dielectric layer from bottom to top. Wherein the fluorescent colored fibers are prepared by mixing colored fibers with various colors and uniformly spraying transparent fluorescent ink paint, and have two anti-counterfeiting characteristics of color matching and fluorescence. The three anti-counterfeiting technologies of refraction, fiber color matching and fluorescent color development are organically combined in the same paper area in a layering mode, the structure is unique, the anti-counterfeiting layers are rich, the counterfeiting difficulty is extremely high, meanwhile, consumers can conveniently carry out authenticity identification in multiple modes of view angle changing, fiber observing, ultraviolet lamp irradiation and the like, and the anti-counterfeiting effect is good. And the system has extremely high safety, interactivity and popularization value.

A system and method to extend a dynamic range of fluorescence measurements. The system includes a neutral density filter stack apparatus including a plurality of neutral density filters. The neutral density filter stack modulates the intensity of light from a source. This modulation improves the ability to detect emissions from a wider-range of fluorophore concentrations, specifically addressing inner-filter effects at higher concentrations that would normally require sample dilution. It can be used in a system in which absorbance and fluorescence measurements are carried out, wherein the intensity of the light source is modulated with the apparatus for the fluorescence measurements. In this hybrid system, the stack modulates the intensity of the excitation light source for fluorescence measurements to be made at very low concentrations of analyte. The hybrid system also includes optics for absorbance measurements to be made at concentrations of analyte that are higher than those detected by fluorescence.

The invention discloses a benzothiadiazole fluorescent probe as well as preparation and application thereof. According to the present invention, through the two-step Suzuki coupling reaction, the 4-pyridyl group and the N-methyl piperazine group are sequentially introduced, such that the benzothiadiazole fluorescent probe for lysosome polarity detection is simply, conveniently and efficiently synthesized; the probe disclosed by the invention has a remarkable positive solvent color effect, and the fluorescence intensity of the probe is reduced along with the increase of the polarity of a medium, so that specific fluorescence enhancement can be realized in a low-polarity lysosome microenvironment. The probe has excellent light stability and is suitable for long-time dynamic fluorescence imaging monitoring.

The invention relates to a method for quantitatively detecting lactoferrin based on electric field driving-cellulose acetate film zone separation and ratio fluorescence, which takes a cellulose acetate film as a separation platform and a fluorescence platform, and utilizes potential difference to drive lactoferrin to generate zone separation. Meanwhile, lactoferrin is coordinated with carbon dot-lanthanide metal ions of the fluorescent probe, lanthanide ions are sensitized through an antenna effect, strong specific fluorescence is emitted, and the lactoferrin is quantitatively detected according to the ratio of the fluorescence intensity of the lanthanide ions to the fluorescence intensity of the carbon dots. The method does not need expensive instruments, has the advantages of high sensitivity, low detection cost, easiness in operation and the like, and is suitable for accurately detecting the content of lactoferrin in complex dairy products.

The invention relates to the technical field of water quality detection, and discloses a method for accurately detecting urea in water by using a fluorescent probe technology, which is characterized in that the content of urea in water is accurately measured by detecting the change amount of fluorescence intensity based on the specific reaction between a fluorescent probe and urea to cause the change of the fluorescence intensity. After a specific fluorescent probe molecule is combined with a urea molecule, a fluorescence emission spectrum of the specific fluorescent probe molecule can generate quantifiable change, and the change and the urea concentration are in a linear relationship, so that quantitative analysis on the urea in water is realized; according to the detection method, high sensitivity and accuracy are realized, fine change of fluorescence intensity can be accurately captured by utilizing a fluorescent probe technology, high-precision detection of low-concentration urea can be realized, the content of urea in water can be accurately determined by setting specific excitation and emission wavelengths and strictly controlling a standard curve, the detection error is effectively reduced, and the detection accuracy is improved. Compared with a traditional method, the detection accuracy is remarkably improved, and more reliable data support is provided for water quality evaluation.