186 results about "Fluorescent quenching" patented technology

The invention relates to the technical field of fluorescent hydrogel, in particular to high-strength and high-stability fluorescent hydrogel as well as a preparation method and application thereof, the fluorescent hydrogel is formed by physical crosslinking of a hydrogel matrix, a rare earth fluorescent complex and a stabilizer, the hydrogel matrix is of a double-network structure formed by physical crosslinking of polyvinyl alcohol and carboxymethyl cellulose; the rare earth fluorescent complex is formed by connecting rare earth metal ions and an organic antenna material through coordination; the stabilizer is trisodium citrate. Compared with other fluorescent hydrogel, the fluorescent hydrogel with high strength and high stability provided by the invention has the advantages that the phenomena of fluorescence decay and fluorescence quenching caused by metal ions and saturated salt solution are avoided, and the fluorescence is kept stable in a wide pH range. Because the fluorescence characteristic is not influenced by environmental corrosion factors, the information can be stably displayed for a long time, and the method can be used for information encryption and anti-counterfeiting in an extreme environment.

The invention discloses a sensing material for detecting atmospheric carboxylic acid, a preparation method, a detection method and application, belongs to the technical field of environmental functional materials, and solves the problems that an existing method is complex in operation and cannot realize real-time online monitoring, the sensing material for detecting atmospheric carboxylic acid is an MOF-802-EDTA-Pt composite film, and the preparation method comprises the following steps: taking 1, 3, 4, 5-tetramethyl-1, 3, 5-tetramethyl-1, 3, 5-tetramethyl-1, 3, 5-tetramethyl-1, 3, 5-tetramethyl-1, 3, 5- The preparation method comprises the following steps: synthesizing an MOF-802 material through a hydrothermal reaction by taking 1, 3, 5-benzene tricarbonic acid (BTC) and aluminum nitrate as raw materials and ethylene diamine tetraacetic acid (Na-EDTA) as a ligand; the preparation method comprises the following steps: dispersing MOF-802 in DMF to form a coating solution, and forming a film on a glass substrate through a pulling method; and then loading platinum nanoparticles, and carrying out solvothermal reaction and vacuum drying to obtain the composite sensing film. The MOF-802-EDTA-Pt composite film has a porous structure and fluorescence characteristics, and detection is realized through a fluorescence quenching effect of carboxylic acid molecules and an MOF skeleton. The method disclosed by the invention is controllable in process and high in material stability, still keeps excellent selectivity under the coexistence condition of interferents such as CO2 and NO2, and is suitable for real-time monitoring of carboxylic acid pollutants in the atmospheric environment.

The invention provides a pathogen viable bacteria detection kit based on endogenous protein activated deoxyribozyme. The kit comprises a deoxyribozyme recognition element and a signal transduction element. The deoxyribozyme recognition element is composed of a substrate chain and an enzyme chain, and the signal transduction element is composed of two DNA reporter probes (Sub-F and Sub-Q), wherein the tail ends of the two DNA reporter probes are respectively marked with a fluorescence staining group and a fluorescence quenching group. The deoxyribozyme recognition element can recognize specific endogenous protein of target pathogenic viable bacteria and activate an enzyme chain to cut a substrate chain to generate two independent substrate chain fragments. And then a signal transduction element is introduced to realize specific output of a fluorescence signal. The kit provided by the invention can realize detection of living salmonella by targeting endogenous protein, can sensitively detect 190 CFU / mL of living salmonella with abundance as low as 0.1%, and has a good application prospect in the directions of food safety detection and clinical examination.

The invention relates to the field of viscosity detection, and provides a fluorescent probe for detecting the viscosity of mask essence as well as a preparation method and application of the fluorescent probe. 4, 4 '-(iminomethylene) bis (N, N-dimethylaniline) which is slightly soluble in water reacts with acid to form auramine hydrochloride, the water solubility of the auramine hydrochloride fluorescent probe is greatly enhanced, the probe in a water phase is converted into heat (non-radiation decay) due to twisted intramolecular charge transfer and excited state energy caused by benzene ring rotation, and fluorescence quenching is shown; when the viscosity of the solvent is increased, rotation of the benzene ring is blocked, excited state energy cannot be converted into heat and is dissipated in a radiation attenuation mode, fluorescence is enhanced, and viscosity detection of the mask essence with the main component being water is achieved based on the principle. According to the present invention, the method has characteristics of simple synthesis, stable property, no interference of solvent polarity during detection, long-term storage and long-term use, rapid and high-specificity viscosity response ability, and quantitative analysis of viscosity.

A method for manufacturing display panel including: forming pixel defining layer on one side of base substrate; forming quantum dot layer, including sequentially forming first quantum dot pattern of at least two quantum dot patterns, forming first quantum dot pattern of one quantum dot pattern including forming quantum dot film capable of emitting light with corresponding colors, quantum dot film including quantum dot body and cross-linkable ligand; performing local cross-linking process on quantum dot film; performing developing process on quantum dot film subjected to local crosslinking process to form first quantum dot pattern in pixel accommodating hole corresponding to corresponding color; after forming first quantum dot pattern of quantum dot patterns, the method includes performing fluorescence property quenching process to quench fluorescence of quantum dot body in quantum dot on surface of first quantum dot pattern and not subjected to crosslinking process. Also provided is display panel and display device.

The invention discloses application of a dual-emission Eu < 3 + > and Cd-MOF material in detection of polluting anions. Experimental results show that the material has an obvious fluorescence quenching effect on CrO4 < 2-> and Cr2O7 < 2->. When the amount of the added CrO4 < 2-> is 2.0 [mu] mol, the fluorescence intensity of the Eu < 3 + > Cd-MOF is quenched to 93.15% (500 nm) and 94.51% (620 nm); similarly, when the addition amount of Cr2O7 < 2-> is 2.0 umol, the fluorescence intensity of the fluorescent powder is quenched to 86.25% (500 nm) and 83.31% (620 nm). Therefore, the dual-emission Eu < 3 + > and Cd-MOF can selectively identify CrO4 < 2-> and Cr2O7 < 2-> ions, and has the advantages of rapidness, simplicity, convenience, sensitivity, accuracy and the like.

The application belongs to the technical field of fluorescent probe detection, and discloses a bimetallic nanocluster fluorescent probe compound and application thereof in preparation of a product for rapidly detecting acetylene. The fluorescent probe compound is a gold-copper bimetallic nanocluster solution modified by adamantane thiol, which is used as a fluorescent probe for acetylene detection. The solution has a clear and controllable preparation process. Through specific proportioning and reaction conditions of cuprous chloride, adamantane thiol, tetrachloroauric acid, sodium borohydride and other reagents, a probe solution with stable fluorescence characteristics can be prepared. The bimetallic nanocluster fluorescent probe compound is applied in preparation of a product for rapidly detecting acetylene. Through specific combination of fluorescent molecules and acetylene gas to trigger the secondary effect of fluorescence quenching, detection is realized, and other substances cannot trigger quenching. At a wavelength of 700 nm, the linear relationship (R 2 >0.99) between the fluorescence intensity and the acetylene concentration realizes accurate quantification of the acetylene concentration, and the minimum detection limit is 0.026 muL / L.

The application discloses an up-conversion fluorescent probe, an isoniazid detection method and a portable isoniazid detection sensor and belongs to the field of biological detection. The up-conversion fluorescent probe is composed of lanthanide-doped core-shell structure up-conversion nanoparticles subjected to acid pickling treatment and p-dimethylaminobenzaldehyde, wherein the core particle diameter of the up-conversion nanoparticles is 25.85-28.85 nm, and the shell layer thickness is 0.98-1.38 nm. The lanthanide-doped core-shell structure up-conversion nanoparticles are used as an energy donor, and the p-dimethylaminobenzaldehyde is used as a specific recognition molecule, and ratio-type fluorescence detection is realized through an inner filter effect. Isoniazid reacts with DMAAB to generate a Schiff base, which causes fluorescence quenching at 475 nm and no change in 655 nm fluorescence, so that the fluorescence color changes from blue to red. Due to the near-infrared excitation characteristics of the up-conversion nanoparticles, the up-conversion nanoparticles are not easily disturbed by background fluorescence, so that rapid quantitative detection of isoniazid in whole blood is realized, and the detection limit is as low as 2.4 μm. The application is simple in operation, strong in anti-interference and suitable for clinical individualized drug monitoring.

The invention belongs to the technical field of chrysin detection, and particularly relates to a dual-emission fluorescent molecularly imprinted polymer as well as a preparation method and application thereof. The method comprises the following steps: preparing carbon dots with different emission wavelengths; carrying out amination modification on the carbon dots; and preparing the dual-emission fluorescent molecularly imprinted polymer. The method also comprises the following steps: respectively adding the dual-emission fluorescent molecularly imprinted polymer into chrysin solutions with different known concentrations, carrying out fluorescence quenching reaction, and establishing a standard curve according to the linear relationship between the detected fluorescence intensity and the corresponding concentration of the chrysin solution; adding the dual-emission fluorescent molecularly imprinted polymer into a solution of a to-be-detected product, and carrying out fluorescence quenching reaction to obtain fluorescence intensity; and calculating the concentration of chrysin in the solution to be detected according to the standard curve. The preparation method is used for solving the technical problems that in the prior art, a single-emission fluorescent molecularly imprinted polymer has defects in the aspects of sensitivity, background fluorescence interference resistance in a complex environment and the like in the detection process.

This invention provides a method for screening β-galactosidase inhibitors, belonging to the field of pharmaceutical technology. The first step of this method uses fluorescence sensing technology to rapidly identify natural products with β-Gal inhibitory activity. The principle is based on the fluorescence quenching property of p-nitrophenol (PNP) on sulfur quantum dots (SQDs); β-Gal catalyzes the hydrolysis of p-nitrophenyl-β-D-galactopyranoside (PNPG) to generate the specific product PNP; in the presence of β-Gal, PNPG can be enzymatically catalyzed to generate PNP, quenching the fluorescence of SQDs; when screened for β-Gal inhibitory activity, the fluorescence of SQDs can be restored. The second step uses affinity chromatography to capture components in samples with β-Gal inhibitory activity. This method involves immobilizing β-Gal on a support material, eluting with a solvent to obtain components that can bind to β-Gal, and then using liquid chromatography-mass spectrometry (LC-MS) to identify the components. This method can rapidly and accurately screen β-Gal inhibitors from natural products.

The invention relates to a method for specifically detecting tetrahydrocannabinol and hydride thereof by utilizing bridged beta-cyclodextrin, and belongs to the technical field of analysis and detection of supramolecular materials. The method comprises the following steps: firstly, combining 1, 6-hexamethylenediamine bridged bis-beta-cyclodextrin with an indicator to form a supramolecular probe; in a buffer system with a pH value of 9-11, tetrahydrocannabinol or a hydride thereof specifically competes to be combined with a cavity and displaces an indicator by utilizing a synergistic inclusion effect of a bridging subject and dissociation difference of guest molecules, so that the system is subjected to fluorescence quenching or color change, and a structural analogue cannabidiol does not generate obvious interference. The method solves the problems that the sensitivity is low and cannabidiol cannot be effectively distinguished in the prior art through cooperation of specific main body construction and environment regulation, has the advantages of being rapid in detection, high in specificity, high in accuracy and the like, and is suitable for environment monitoring and field screening.

The invention relates to the technical field of photovoltaic modules, and particularly discloses a tetraphenyl ethylene-benzotriazole derivative compound and application thereof in the photovoltaic field. The absorption spectrum of the tetraphenyl ethylene-benzotriazole derivative compound disclosed by the invention can be subjected to red shift to 420 nm, so that high-energy ultraviolet light can be completely absorbed; the maximum emission wavelength of a fluorescence emission spectrum is more than 440nm and even can reach 500nm, so that the light utilization level of the crystalline silicon solar cell is improved; the absolute light-emitting quantum efficiency is very high, and the converted wavelength can be better utilized by a photovoltaic device. The substituted tetraphenyl ethylene part contained in the derivative compound has AIE performance, and the fluorescence quenching effect of traditional small organic molecules in high concentration, solid state and aggregation state is avoided. The light conversion film can overcome the problem that the fluorescence quantum yield is remarkably reduced in the laminating process, the performance of the film is not affected when the phenomena of precipitation, agglomeration and the like of auxiliaries in the film occur, and the light conversion film is used for preparing a photovoltaic module.

The invention relates to the technical field of biological medicine, in particular to a TREM-1 targeted fluorescent molecular probe as well as a preparation method and application thereof, and discloses a fluorescent molecular probe named as' TREM-1 targeted fluorescent molecular probe as well as a preparation method and application thereof '. The invention aims to solve the problems of large molecular weight, poor pharmacokinetic performance, limited tissue penetration, high imaging background and poor imaging timeliness of the existing antibody fluorescent probe. The probe comprises a TREM-1 targeting module (TDM), a near-infrared fluorescence reporter group, a dark quenching group and a conformational sensitive connecting arm (CSL). The fluorescence of the probe is quenched before the probe is combined with TREM-1, and after the probe is combined with a target spot, TDM specific binding induces CSL conformation rearrangement, so that a reporter group and a quenching group are spatially separated, fluorescence resonance energy transfer (FRET) is relieved, and fluorescence activation is realized. According to the invention, rapid, high-contrast and low-background fluorescence imaging of atherosclerotic plaques is realized, and the probe is small in molecular size, strong in tissue penetrability and rapid in-vivo clearing.

This invention belongs to the field of compound technology and provides a DNA-intercalating fluorescent quenching compound, its preparation method, and its application. This invention provides a DNA-intercalating fluorescent quenching compound that exhibits absorption in the visible light region and certain DNA sequence selectivity. The DNA-intercalating fluorescent quenching compound provided by this invention can be further used to design fluorescence analysis systems for restriction endonuclease EcoRV and DNases. The DNA-intercalating quenching compound can achieve relevant fluorescence analysis by combining with fluorescent molecules in a covalent-free manner, reducing the need for chemical labeling steps, thereby improving efficiency and reducing detection costs, and showing good application prospects in related analyses.

The application discloses a fluorescence enhancement anchor agent based on a fluoroboron dipyrrin-tetrazine dye for inflation microscopy technology, and belongs to the technical field of biochemical analysis. The fluorophore of the fluorescence enhancement anchor agent is shown in formula (I), formula (II) or formula (III): the tetrazine group carried by the fluorescence enhancement anchor agent is removed from fluorescence quenching through a biological orthogonal reaction with a drug probe, and the drug probe is shown in formula (IV): the fluorescence enhancement anchor agent can covalently and non-covalently anchor small molecules in a hydrogel network based on a tetrazine biological orthogonal reaction, and realizes inflation microscopic fluorescence imaging of a double fluorescence enhancement mechanism. In addition, the drug probe selects a non-covalent drug, gefitinib, as a probe core, is modified with a BCN click handle, and successfully realizes in-situ fluorescence inflation microscopic imaging of an EGFR drug-target, thereby providing a new tool for research and clinical research on non-covalent drug target co-localization information of exosomes.

The invention provides a light-emitting auxiliary material and a preparation method and application thereof, and belongs to the technical field of light-emitting materials, the structural formula of the light-emitting auxiliary material is shown in the general formula I. The light-emitting auxiliary material takes 9, 9-phenylalkyl fluorene as a parent nucleus, aryl and arylamine groups are connected to the two sides of fluorene of the 9, 9-phenylalkyl fluorene respectively, 9-phenylalkyl fluorene has relatively high glass transition temperature and quantum fluorescence efficiency, the stability and luminous efficiency of the compound can be effectively improved, the energy levels of the highest occupied molecular orbital and the lowest unoccupied molecular orbital can be flexibly adjusted by introducing an electron-donating group arylamine, and the energy barrier of hole injection can be effectively reduced; meanwhile, the other side is connected with an aryl group, so that a conjugated system can be effectively extended, a fluorescence quenching phenomenon caused by intermolecular pi-pi accumulation and excessive molecular aggregation is reduced, the service life of an OLED (Organic Light Emitting Diode) device can be effectively prolonged, the luminous efficiency of the OLED device can be effectively improved, and the driving voltage can be reduced by utilizing the light-emitting auxiliary material.

The application belongs to the technical field of functional polyurethane materials, and more particularly relates to a polyurethane fluorescent material applicable to bacterial detection and a preparation method thereof. The polyurethane pre-polymer is obtained by pre-polymerization of a hydrophobic polyether monomer, isocyanate, a catalyst and a hydrophilic solvent; a chain extender is added to the pre-polymer for chain extension reaction, and then a capping agent is added for capping reaction, and after curing, a polyurethane elastomer is obtained; the polyurethane elastomer is mixed with an ethanol solution, curcumin is added, and stirred uniformly to obtain a fluorescent polyurethane solution, and curing obtains a polyurethane-based fluorescent material. The polyurethane fluorescent material applicable to bacterial detection is designed through a polyurethane segment, ensures solid-state light emission of curcumin, does not cause fluorescence quenching, ensures activity of a heat-sensitive base material at room temperature, and the fluorescent color is different under different bacterial concentrations, and the response is sensitive.

The invention discloses a CPN-Y2-Cl cation framework material as well as a preparation method and application thereof. The CPN-Y2-Cl cation framework material is constructed by carrying out quaternization reaction on tetra (1-imidazole phenyl) ethylene and 5, 5 '-bromomethyl-2, 2'-dipyridyl, and is obtained by carrying out anion exchange. The material has rapid and efficient adsorption performance on I3 <-> in a water phase, and still shows good selectivity in the presence of various competitive anions. Meanwhile, the material has obvious fluorescence quenching in the process of acting with I3 <->, and rapid detection of I3 <-> in water can be realized. The material designed by the invention is stable in performance, the preparation process is simple and convenient, and the prepared organic cation framework material has dual functions of adsorption and fluorescence recognition, and has a wide application prospect in the fields of treatment and real-time monitoring of radioactive iodine polluted water.

The invention belongs to the technical field of fluorescent dyes, and particularly relates to a phenanthroline-based double-BODIPY fluorescent dye with an asymmetric structure as well as a preparation method and application of the phenanthroline-based double-BODIPY fluorescent dye. The preparation method comprises the following steps: mixing a chlorinated BODIPY derivative with 1, 10-phenanthroline-5-amino, adding palladium acetate, tri-tert-butylphosphine, potassium tert-butoxide and toluene, and carrying out a heating reflux reaction; and after the reaction is finished, cooling, reducing pressure to remove toluene, dissolving the obtained product with dichloromethane, washing, drying, concentrating, and separating and purifying through silica gel column chromatography to obtain the target dye. The unique asymmetric structure in the prepared target dye destroys the planarity and symmetry of molecules, effectively weakens the fluorescence quenching effect caused by molecular self-absorption and pi... pi accumulation, and further has relatively large Stokes shift and high solid-state luminous efficiency; good application potentials are shown in a plurality of fields such as high-performance solid-state light-emitting devices and biological probes.

The invention relates to a preparation method of a biosensor, in particular to a construction method of an acetylcholin esterase (at) amorphous covalent organic framework (AChE (at) aCOFs-DB) photoenzyme integrated biosensor, and belongs to the technical field of biosensors. According to the method, an in-situ growth mineralization strategy is adopted, effective packaging of AChE in aCOFs-DB is achieved, the fluorescence performance of aCOFs is enhanced through a hydrogen bond auxiliary intramolecular rotation limitation design, and meanwhile the structural stability and catalytic activity of AChE are improved; the biosensor with high sensitivity and high selectivity is constructed based on the synergistic effect of fluorescence characteristics and enzyme catalytic performance; the sensor can be used for sensitive detection of organophosphorus pesticides such as chlorpyrifos, and the detection limit can reach a nanogram / milliliter level; the detection principle is as follows: AChE catalyzes a substrate to generate a product, and fluorescence quenching is caused by an inner filtering effect; when the organophosphorus pesticide (such as chlorpyrifos) exists, the AChE activity is inhibited, the catalytic capability is reduced, and a fluorescence signal is recovered, so that quantitative detection of the pesticide is realized; the preparation method is simple and convenient to operate and controllable in structure, is suitable for rapid detection of organophosphorus pesticides in agricultural products and environmental samples, and has a good application prospect.

This invention discloses a polycyclic compound and an organic electroluminescent device containing the same. The invention introduces a bridged ring structure to reduce the electron-donating ability of nitrogen atoms, and further weakens this ability through a bridged ring and benzene ring structure, avoiding a redshift in the material's emission. Compared to the benzene ring, the twisted structure of the bridged ring weakens the intermolecular interactions caused by this planar configuration, which is more conducive to the dispersion of dopants in the host material, effectively avoiding fluorescence quenching and improving luminescence efficiency. Simultaneously, the use of a double boron framework allows the material to maintain a narrow half-width at half-maximum (WHM), resulting in devices fabricated using the compound of this invention exhibiting excellent performance in terms of efficiency and lifetime.

The invention discloses a fluorescent probe based on an ESIPT principle and application of the fluorescent probe in detection of total iron, ferrous iron and ferric iron. The probe OHNH contains a phenolic hydroxyl group, generates strong fluorescence through ESIPT, and has the advantages of good light stability, high fluorescence quantum yield, good water solubility, difficult hydrolysis, simple synthesis and the like. Fe and OHNH can generate specific complexation, the ESIPT process is influenced, and fluorescence quenching is caused. Fe is easily oxidized into Fe under the heating condition of a drying oven, and then fluorescence quenching is also triggered. Based on the principle, high-selectivity and high-sensitivity detection of total iron, ferrous iron and ferric iron can be realized. The method is low in cost, easy and convenient to operate, high in specificity and high in accuracy, and visual detection can be achieved. Furthermore, the method can be used for valence state distinguishing and content determination of iron in complex matrixes such as medicines, foods and water bodies, and has important practical application value.

The present application relates to a kind of fluorescent crystalline porous organic salt and its preparation method and application, belong to crystalline porous organic salt technical field.The preparation method of the fluorescent crystalline porous organic salt of the present application, first tetra (4- amidinophenyl) ethylene hydrochloride is dissolved in 1, 4-dioxane aqueous solution, obtain solution A;Then 4, 4'-diphenyl disulfonic acid is dissolved in 1, 4-dioxane aqueous solution, obtain solution B;Finally solution A and solution B are mixed, and the room temperature is above 8h, filter, obtain fluorescent crystalline porous organic salt, structure is as shown in formula I.The fluorescent crystalline porous organic salt structure is stable, has permanent porosity, to heavy metal ions (with Fe 3+ As representative) has very good fluorescence quenching effect, can be applied to the detection of heavy metal ions.

The invention discloses a terbium-doped benzene polycarboxylic acid-metformin HOF material and application thereof in detection of an explosive precursor sodium hypochlorite, and belongs to the technical field of fluorescent probes and fluorescence detection. The terbium-doped benzene polycarboxylic acid-metformin HOF material is formed by coordination compounding of an HOF matrix and rare earth metal ions Tb < 3 + >, and the HOF matrix is formed by self-assembly of benzene polycarboxylic acid compounds and metformin hydrochloride through intermolecular hydrogen bonds. The material can generate high-selectivity fluorescence quenching response to sodium hypochlorite (NaClO) through characteristic fluorescence emission (5D4-7F5 transition) of Tb < 3 + > at 545nm, is low in detection limit and wide in linear range, and can be used for realizing rapid and high-sensitivity detection of low-concentration NaClO. And the method has great significance in blocking the synthesis of explosives based on NaClO.

The invention discloses a trithiophene type fluorescent probe for detecting total polar substances of edible oil as well as a preparation method and application of the trithiophene type fluorescent probe. The preparation method comprises the following steps: directly carrying out a coupling reaction on 4-bis (4-methoxyphenyl) amino] phenyl]-[2, 2 ': 5', 2 ''-trithiophene-5-formaldehyde and 4-bis (4-methoxyphenyl) aminophenylboronic acid to prepare 5''-[4-[bis (4-methoxyphenyl) amino] phenyl]-[2, 2 ': 5', 2 ''-trithiophene-5-formaldehyde, and reacting the compound with 4-methylquinoline to synthesize the probe (E)-4-methoxy-N-(4-methoxyphenyl)-N-[4-(5''-(2-(quinoline-4-yl) vinyl)-[2, 2 ': 5', 2 ''-trithiophene-5-formaldehyde. The compound can selectively detect the polarity of edible oil, yellow fluorescence is quenched after the polarity of the edible oil is increased, and the compound can be used as a fluorescent probe for detecting the polarity of the edible oil.

The application discloses a kind of photoactivation manganese ion bridging type deoxyribozyme probe preparation and its application in Cistanche inhibiting acetylcholinesterase activity.The probe is pSD@MnO2 Composite structure, which is composed of manganese dioxide nanosheet and functional nucleic acid assembly adsorbed on its surface, the assembly includes S chain labeled with fluorescence / quenching group and containing deoxyribozyme cleavage site, and pD chain partially hybridized with S chain and containing photocleavage site.Its preparation includes nucleic acid probe assembly, MnO2 Nanosheet complexing and purification steps.When applied, AChE catalytic product decomposes MnO2, releases Mn 2+ And nucleic acid chain; after centrifugation, pD chain is cut by ultraviolet light activation trigger, and released DNAzyme is cut under the assistance of Mn 2+ It produces amplified fluorescence signal; by comparing signal change before and after adding inhibitor, inhibition activity can be quantitatively evaluated.The application combines photocontrol activation with enzyme cascade amplification, realizes high sensitivity and operation synchronism of detection process, and is especially suitable for high-throughput rapid screening of AChE inhibitor in Cistanche and other natural products.

The invention discloses a dual-response type near-infrared two-region quantum dot nanoprobe as well as preparation and application thereof, and belongs to the technical field of biomedical nanomaterials and molecular imaging. The quantum dot nanoprobe comprises an inner core and a shell, wherein the shell is coated outside the inner core; the inner core comprises a near-infrared emission quantum dot core, and the surface of an NIR-II quantum dot is connected with a response peptide and a quencher; the shell is prepared from a polylactic acid-glycolic acid copolymer, polylactic acid, polycaprolactone, a polylactide-polyethylene glycol copolymer, a polylactide-polycaprolactone copolymer, a polysulfide block copolymer and the like. According to the NIR-II quantum dot nanoprobe disclosed by the invention, a response peptide chain and a fluorescence quencher are introduced through chemical modification, and a signal off-on function is realized, so that an activated fluorescent probe with high specificity and high contrast is constructed; the nano-composite particle with controllable particle size, adjustable fluorescence and stable structure is formed, has targeting property, responsiveness and biocompatibility, and is suitable for accurate real-time imaging in a complex in-vivo environment.

The invention belongs to the technical field of antibacterial materials, and particularly relates to a zwitterionic photosensitizer material, nanoparticles and a preparation method and application of the zwitterionic photosensitizer material and the nanoparticles. The structural formula of the zwitterionic photosensitizer material is shown in the specification, wherein x is any integer between 3 and 5; r1 and R2 groups are shown in the specification. The zwitterionic photosensitizer material based on sulfonation has excellent hydrophilicity and biological activity, can achieve an efficient sterilization effect at a low dosage, and has efficient curability on mouse living body wound infection, so that the zwitterionic photosensitizer material can be used for preparing a medicine for treating wound infection, and the problems that in the prior art, aggregation causes a fluorescence quenching effect, and the toxicity is poor are solved. And the problem of poor antibacterial treatment effect caused by reduction of ROS yield due to aggregation is solved.

The invention discloses a cell single-molecule mechanical force sensor for single-molecule mechanical force detection in a cell phagocytosis process as well as a preparation method and application of the cell single-molecule mechanical force sensor. The sensor comprises a microsphere substrate and a plurality of double-stranded DNA mechanical probes modified on the surface of the microsphere substrate, the probe is composed of a first single-stranded DNA and a partially complementary second single-stranded DNA and forms an FRET or fluorescence quenching pair, when a pulling force applied to the probe by a receptor-ligand effect exceeds a preset melting threshold value in a process of swallowing or wrapping microspheres by a cell, the double-stranded DNA generates melting or conformational change and generates fluorescence signal change, and the fluorescence signal change is detected by the first single-stranded DNA and the partially complementary second single-stranded DNA. Therefore, the detection of the monomolecular mechanical force of the phagocytic interface is realized. By adjusting the geometric conformation and sequence design of the probe, a probe library with different melting force thresholds can be constructed, and quantitative analysis and spatial distribution characterization of mechanical force in the phagocytosis process are realized. According to the application, a three-dimensional phagocytic interface can be truly simulated, and an effective tool is provided for revealing a mechanism for regulating and controlling endothelial cell phagocytic behaviors through blood flow mechanics and screening related disease drugs.

The invention relates to the technical field of analytical chemistry and nano sensing materials, and discloses a quantum dot microsphere fluorescent probe for trace quaternary ammonium salt detection and a preparation method thereof, and the probe is prepared from porous CdSe quantum dot microspheres, fluorescein isothiocyanate and a buffer solution. The FITC is used as an energy donor, the porous microspheres are used as an energy receptor, the FITC and the porous microspheres close the distance through electrostatic adsorption, a fluorescence resonance energy transfer system with an open initial state is constructed, and fluorescence quenching of the FITC and fluorescence enhancement of the quantum dots are shown. When quaternary ammonium salt is detected, the FITC is separated from the surface of the microsphere by utilizing a hydrophobic competitive replacement mechanism, the FRET process is blocked, the fluorescence of the FITC is recovered, and the fluorescence of the quantum dots is reduced, so that the detection is realized through the change of a ratio fluorescence signal. The method has the advantages of high detection sensitivity, good selectivity, high response speed, strong anti-interference capability and the like, and realizes rapid quantitative detection of trace long alkyl quaternary ammonium salt in a complex environment.