206results about How to "Large Stokes shift" patented technology

The invention belongs to the field of bio-medical instruments, and in particular relates to a system and a method for quantitative detection of test strips on the basis of continuous fluorescent-substance markers. The system comprises a continuous fluorescent-substance marker test strip, a test strip frame, a lighting system, an imaging system, a fluorescent image receiver, a signal amplifier, an analog / digital converter, a data processing-controlling system, an output display device, a printer, a keyboard and an IC card matched with the test strip. The data processing-controlling system reads parameters of the IC card and then controls the test strip frame to move so as to ensure that the light emitted by the lighting system is reflected via a dichroic mirror and then automatically scans the test strip; acquired characteristic wavelength reflection fluorescence is transmitted to the data processing-controlling system for optical density identification and concentration calculation via the fluorescent image receiver, the signal amplifier and the analog / digital converter; and the output display device displays results. The invention can quickly and accurately realize the quantitative or qualitative detection of single-component and multi-component samples. The system has the characteristics of high detection sensitivity, objective results, flexible use and the like.

The invention discloses a two-photon formaldehyde fluorescent probe and preparation and application thereof. The probe is a novel formaldehyde probe taking 1,8-naphthalimide as a two-photon fluorogen on the basis of an intramolecular charge transfer mechanism. Probe molecules have good light stability and a large Stoke's shift, the probe can well detect the formaldehyde concentration in a neutral buffer solution, and meanwhile compared with other aldehyde compounds, the probe has good specificity on formaldehyde. It is well proved through two-photon confocal fluorescence microscopic imaging experiments that the probe can permeate through a cell membrane to enter cells and can detect a change of the formaldehyde concentration in the cells, and an effective research tool for researching the physiological action of formaldehyde in the cells is provided.

Fluorescent dyes useful for detecting a target material in biological assays an electron donating moiety which is linked by a conjugated π-electron bridge to an electron accepting moiety. The π-electron bridge includes at least one carbocyclic ring structure or heterocyclic ring structure. The electron accepting moiety is a carboxylic acid, a salt of a carboxylic acid, or has the formula: wherein: X8 is selected from the group consisting of H, CH3, and (CH2)n6-Z2−, where Z2− is a monovalent anion; and n6 is an integer from 1 through 10; and Q3 is O or S.

The invention discloses a kit for quantitative detection on an O type foot-and-mouth disease virus antibody through fluorescence immunoassay magnetic particles. The kit consists of O type foot-and-mouth disease virus antibody negative serum, O type foot-and-mouth disease virus antibody positive serum, VP1 coating magnetic beads, a biotinylation goat-anti-pig antibody, a streptavidin marking fluorescent substance, a cleaning solution and an enhancing solution. The magnetic beads used in the kit have relatively large binding areas, so that the detection range is greatly increased, the reaction time is shortened, and the sensitivity is improved. The kit has a relatively wide stimulation spectrum and a relatively narrow emitting spectrum, the cost can be reduced, and the sensitivity can be improved; compared with a conventional fluorescent substance, the kit is relatively wide in detection range and relatively good in specificity. Due to adoption of a streptavidin-biotin signal amplification system, the detection sensitivity is further improved, and the kit is relatively high in sensitivity when being compared with ELISA (Enzyme-Linked Immuno Sorbent Assay) and chemiluminiscence. Together with a full-automatic detector, on-site automatic operation can be achieved, one or more samples can be simultaneously detected, and the kit is simple, convenient and rapid to operate and low in price.

The invention discloses a red-light emission fluorescent carbon dot with an up and down conversion function and a preparation method of the red-light emission fluorescent carbon dot. The particle size of the carbon dot is 10-50nm; the position of a fluorescence emission peak generated under the irradiation of exciting lights with different wavelengths is 600-670nm; the fluorescence quantum yield is greater than 40%; and the preparation method comprises the following steps: dissolving a carbon precursor into a liquid organic compound to form a mixed reaction solution; heating and carrying out heat preservation to form a brownish red solution; and washing the solid matters separated from the brownish red solution, so as to form the carbon dot. The carbon dot disclosed by the invention has the advantages of up and down conversion and red-light emission, high fluorescence quantum yield and relatively large stokes shift, and has a wide application prospect in the fields such as fluorescent tag imaging, drug delivery, disease diagnosis, analysis detection and the like; and meanwhile, the preparation process is simple and rapid, convenient to operate, high in yield, free of complicated and expensive equipment, low in cost, and easily achieves large-scale production.

The present invention discloses a novel fluorescent probe capable of specifically recognizing cysteine, wherein the molecular structure formula is defined in the specification. According to the present invention, the fluorescent probe can distinguish the mercapto-containing cysteine from the mercapto-free amino acid region, can distinguish the cysteine from the homocystine and the glutathione having the similar structure, emits red light during cysteine detection, can reduce the background interference and the damage of light on tissue cells in biological applications, exhibits great Stokes shift, can reduce self-absorption so as to improve the sensitivity, can be used for the fluorescence sensing analysis of the cysteine in environments or biological samples, and has advantages of good selectivity to cysteine, high sensitivity, strong interference resistance, and good application prospect.

The invention discloses an NGAL time-resolved fluoroimmunoassay nanometer immunochromatographic quantitative detection test paper strip and a preparing method thereof. The test paper strip comprises a backing substrate plate. The backing substrate plate is provided with a nitrocellulose membrane, a sample combining pad and a water absorbing membrane. The sample combining pad and the water absorbing membrane are respectively laminated on two ends of the nitrocellulose membrane. The sample combining pad is covered with an NGAL monoclonal antibody labeled with a time-resolved fluorescent substance. The nitrocellulose membrane is provided with a detection line and a quality control line. The detection line is covered with an NGAL monoclonal antibody of another epitope. The quality control line is covered with goat anti-rat IgG. The test paper strip and the method are characterized by high sensitivity, high specificity, good stability, no radioactive contamination, and the like and can be widely applied to NGAL clinical immunoassay and scientific research.

The invention belongs to the field of medical materials, and discloses a benzylidene indandione compound and a preparation thereof and an application in specific imaging of a lipid droplet. The structure of the benzylidene indandione compound is as shown in a formula I. The benzylidene indandione compound has the advantage of aggregation-induced emission, and the defects of aggregation-induced quenching of a traditional fluorescent dye can be effectively overcome, so that the specific fluorescence imaging of the lipid droplet in a living cell can be achieved; furthermore, the benzylidene indandione compound has a two-photon absorption cross-section which is high in living cell penetration rate, high in signal to noise ratio, small in cytotoxicity, large in stokes shift and large in near infrared region. The formula I is as shown in the specification.

The invention relates to an aggregation-induced emission principle-based fluorescent probe, its preparation method and use and an endotoxin detection method utilizing fluorescent probe aggregation-induced emission characteristics and iodine ion fluorescence quenching removal characteristics to realize fast, visual and qualitative or quantitative detection of endotoxin.

The invention discloses amphiphilic segmented copolymers, nanoparticles containing the amphiphilic segmented copolymers, a preparation method of the amphiphilic segmented copolymers and a use of the nanoparticles. The amphiphilic segmented copolymers are shown in the structural formulas (I) to (IV). In the structural formulas (I) to (IV), R1 represents H or methyl, R2, R3 and R5 represent H, alkyl or aryl, R4 represents hydroxyl or methyl, x is an integer of 3-20, Spacer is a spacer arm, the spacer arm is optional, and when the spacer arm exists, the spacer arm is one of an ester group, an alkyl group, a triazole group and a thioether group. The nanoparticle obtained by chelating of the amphiphilic segmented copolymer and rare earth ions has good biocompatibility, has excellent fluorescence imaging performances and MRI imaging performances and has a wide application value in the field of medicine and biology and especially in breast cancer diagnosis and treatment.

The invention discloses a malononitrile derivative near-infrared hydrogen sulfide fluorescent probe as well as a preparation method and application thereof. The probe has a structure represented by aformula I shown in the description. The preparation method comprises the following steps: firstly, mixing isophorone, malononitrile and piperidine, performing heating reflux under the protection of aninert gas, performing purification, mixing the obtained purified product, p-hydroxybenzaldehyde and piperidine, performing heating reflux under the protection of an inert gas, performing purification, mixing the obtained purified product, urotropine and trifluoroacetic acid, performing heating reflux under the protection of an inert gas, performing purification, finally mixing the obtained purified product, 2,4-dinitrobenzenesulfonyl chloride and triethylamine, performing a reaction under stirring at room temperature, and performing purification to obtain the fluorescent probe. The fluorescent probe provided by the invention has large Stokes shift (229 nm), a longer fluorescence emission wavelength (653 nm) and high sensitivity, can be used for specific detection of biological hydrogen sulfide, and has good biofilm permeability and low cytotoxicity; and the fluorescent probe has a simple synthetic route, a high yield and large practical values.

The invention discloses a large Stokes shift shift and near infrared fluorescence emitting new rhodamine fluorescent dye and a synthetic method thereof, an intermediate can be obtained by catalytic hydrogenation reduction, oxalaldehyde condensation, sodium borohydride reduction, Vilsmeier formolation, acid catalyzed demethylation and other reaction, the intermediate is reacted with diphenyl keto acid to obtain the target product rhodamine fluorescent dye. Compared with fluorescent dyes in the prior art, the new rhodamine fluorescent dye prepared by the synthetic method has high light stability, the fluorescence emission wavelength is in the near infrared region (-700 nm), and the new rhodamine fluorescent dye has a large Stokes shift (-100 nm) and higher fluorescence quantum yield (0.28), and can be used in luminescent materials, biological fluorescence probes and fluorescence imaging and other fields.

The invention discloses a benzofuran quinoline type biological probe and a preparation method thereof, and application of the benzofuran quinoline type biological probe in detecting a G-quadruplex structure and in the mechanism of action of cryptolepine and G-quadruplex, wherein the biological probe is high in fluorescence intensity and excellent in fluorescence property, and can be applied to specially detecting the G-quadruplex structure and researching the mechanism of action of a cryptolepine derivative and the G-quadruplex. The invention relates to the research whether the cryptolepine derivative acts on the telomere G-quadruplex or the C-MYCG-quadruplex in the promoter region, or on other G-quadruplex structures in vivo; the detection method has the advantages of simple, convenient and quick operation, good selectivity and obvious visualization; the shortcomings of unavailable in-vivo detection, high price, high requirement equipment, relatively complex technical operations and the like of other detection methods are overcome.

The invention relates to the technical field of organic synthesis, in particular to a compound based on aggregation-induced emission (AIE) and excited state proton transfer (ESIPT) and a preparation method and application in biological detection. The compound has the structure shown in a formula (I), aldehyde group treatment is performed based on a tetraphenyl ethylene based derivative to obtain an intermediate, the intermediate is further condensed with 2-amino thiophenol under certain conditions to obtain a target compound. The compound I is a fluorescent material novel in structure and meanwhile having the two mechanisms of aggregation-induced emission (AIE) and excited state proton transfer (ESIPT), shows large Stokes shift (greater than 200 nm), does not produce fluorescence quenching in high concentration, and has the advantages of having good light stability and high solid-state fluorescence quantum yield (0.97) and the like. Based on the advantages, the compound is applied to imaging of biological mercaptan in cells.

The invention relates to a zero-dimensional lead-free perovskite fluorescent material as well as preparation and application thereof, and belongs to the technical field of lead-free perovskite fluorescent materials and luminescence application. The fluorescent material is KxCuyNa1-yCl1 + x, x is larger than 0 and smaller than or equal to 10, y is larger than 0 and smaller than or equal to 1, and the fluorescent material KxCuyNa1-yCl1 + x has the advantages of being high in fluorescence quantum yield, large in Stokes shift, low in cost and the like and can serve as an ultraviolet light-emittingmaterial to be applied to electroluminescent devices. And a ball-milling solid-phase reaction method is adopted for preparation, operation is easy, reaction time is short, and the method is suitablefor batch production.

The invention provides an anti-blue-ray quantum dot membrane and a preparation method thereof. The anti-blue-ray quantum dot membrane prepared by the method is capable of using a high-molecular polymer as a base material, through homogeneous dispersion and compounding of quantum dots in a certain proportion and concentration, curing and forming; the quantum dots dispersed in the membrane absorb ablue ray and are excited by the blue ray, and photochemistry down-conversion is realized; and an anti-blue-ray technical effect is finally realized. The quantum dot membrane is a transparent materialas a whole, and comprises a light conversion layer and a protecting layer covering the exterior of the light conversion layer. The quantum dots are uniformly distributed in the light conversion layer.

The invention relates to a novel rhodafluor fluorescent dye with characteristics of large stokes shift and near-infrared fluorescence emitting, and a synthesis method thereof, wherein catalytic hydrogenation reduction, glyoxal condensation, sodium borohydride reduction, Vilsmeier formulation, acid-catalyzed demethylation and other reactions are performed to obtain the intermediate, and the intermediate and diphenyl keto acid react to obtain the target product rhodafluor fluorescent dye. According to the present invention, compared with the conventional fluorescent dye, the obtained novel rhodafluor compound of the present invention has characteristics of high photostability, fluorescence emission wavelength in the near-infrared region (-660 nm), large stokes shift (-90 nm) and high fluorescence quantum yield (0.62), and can be used for the fields of light emitting materials / biological fluorescent probes, bioluminescence imaging and the like.

The invention discloses a two-photon deep red emission fluorescent probe for imaging cell membranes in tissues based on molecular rotors. The chemical name of the two-photon deep red emission fluorescent probe is N,N-di((4-(2(minute)-(4(second)-dodecyl)pyridine-4(second)iodide)ethylene)phenyl)phenylamine, and a chemical structural general formula is as shown in a formula (I). The invention also discloses application of the two-photon deep red emission fluorescent probe in marking or displaying cell membrane forms in the tissues and in living cells. A test verifies that the two-photon deep red emission fluorescent probe can be used for uniformly and continuously dyeing the cell membranes, bright two-photon deep red light can be emitted after the two-photon deep red emission fluorescent probe is bound to high-viscosity cell membranes because the two-photon deep red emission fluorescent probe is a rotor type molecule, the two-photon deep red emission fluorescent probe is indicated to have a very good prospect by being used as a cell membrane fluorescent probe, and the blank of a cell membrane probe in tissue imaging is hopefully to be filled; meanwhile, the two-photon deep red emission fluorescent probe has the characteristics that the application range is wide, the light stability is good, the cytotoxicity is low, and the cell membranes can be specifically imaged in the living cells.

The invention provides a pepsinogen I / pepsinogen II detection kit, and belongs to the technical field of fluorescence immunochromatography in medical immunology. The pepsinogen I / pepsinogen II detection kitwhich is a detection kit of fluorescence quantitative immunochromatography, comprises a detection card, and is characterized in that the detection card is provided with a PVC board, a sample pad, a combination pad, a chromatography membrane and a water absorption paper in sequence; and the chromatographic membrane comprises a detection region and a quality control region, a detection regionof an anti-PG I monoclonal antibody and a PG II monoclonal antibody are coated with the detection region, and a sheep anti-mouse IgG antibody is coated with the quality control region. Test samples ofthe reagent kit are human serum, plasma or whole blood samples, and good detection specificity, higher sensitivity, simple and convenient operation and stable fluorescent markers are achieved to ensure the accuracy of the detection.

This invention is near-infrared fluorescent probe for intracellular zinc ion test. The syncetic process is as followings: A.mix cyanine dyes Cy.7 and complexing group in the weight propotion of 1:5-10, resolve the mix in N,N-dimethyl formamide, and react at 60-70deg C for 2-5 hours with the protection of inactive gas; B. Cool the production A to 10-20deg C, dry blowing with depression, resolve in aether, add water for extraction, the extraction liquor I obtained, then add acetic ester for extraction, the extraction liquor II obtained; C. Add anhydrous addex-magnesium in liquor II for desiccation, dry blowing with depression at 30-40deg C, get rid of acetic ester for the final production. The near-infrared fluorescent probe has a good cellular osmosis and little side effect. In particular, it's seligible for cellular zinc ion test.

The invention provides a preparing method of a double-light-emitting transition metal ion doped semiconductor quantum dot, and belongs to the technical field of chemical engineering. The method includes mixing an acetate, sulfur powder and an oil phase solvent to obtain a mixed solution, heating the mixed solution to 200-260 DEG C at a speed of 10-30 DEG C / min, maintaining the temperature for 10-120 min to form mixed-solution crystal nucleuses, adding a zinc precursor solution into the obtained mixed-solution crystal nucleuses, heating to 220-280 DEG C at a speed of 10-30 DEG C / min, maintaining the temperature for 10-120 min to form a zinc sulfide shell mixed solution, and adding a solvent into the obtained zinc sulfide shell mixed solution to obtain the double-light-emitting transition metal ion doped semiconductor quantum dot. The method is simple. Experiments show that the color rendering index after the quantum dot is prepared into white-light LEDs can reach 95, and the luminous efficiency is 701 m / W.

A silver nanocluster fluorescent probe based on polyethyleneimine protection and application thereof in detecting metronidazole belong to the technical field of fluorescent probes. Silver nanoclustershave great Stokes shift (about 90 nm), and can exist in a solution with extreme acidic pH and high ion concentration and release stable fluorescence when exposed to ultraviolet for long time; all these characteristics are good for the extensive application of the nanoclusters in medicine and biological fields. The silver nanocluster probe in Tris-HCl buffer solution is used to detect metronidazole; the results show that the linear range is 0-10 mu M, and a detection limit is 0.01 mu M. Meanwhile, the silver nanocluster probe has successfully carried out entity detection on metronidazole in urea and achieved good results, it is indicated that the silver nanocluster probe is capable of detecting metronidazole residue in body fluid of a human body.

The invention discloses a fluorescence probe used for rapid identification of phenylthioalcohol (PhSH), and applications thereof, and belongs to the technical field of chemical analysis detection. Thestructure formula of the fluorescence probe is disclosed in the invention; the fluorescence probe is high in selectivity and sensitivity, excellent in anti-interference capability, is capable of emitting red light, and is large in Stokes shift. The tissue penetrability of long wavelength emission (red light or near infrared light) is excellent, and background interference is low; large Stokes shift is capable of reducing self absorption and autofluorescence interference, and increasing detection sensitivity. The above excellent performance shows that the application value of the fluorescenceprobe in the field of environment and biological detection is high.

The invention provides a lipid droplet targeting carbon dot and a preparation method and application thereof. The fluorescent carbon dot takes 4-(1-piperidyl) aniline as a raw material and absolute ethyl alcohol as a solvent, the raw material and the solvent react in a high-pressure reaction kettle at the temperature of 160 DEG C for 12 h, a crude product obtained after the reaction is purified through silica gel column chromatography, petroleum ether and ethyl acetate in different proportions are taken as eluents, and rotary evaporation and further drying are carried out to obtain the purified fluorescent carbon dot. The carbon dots can quickly penetrate through cell membranes within 10 seconds and gather in lipid droplets, and can be used for ultrafast no-wash lipid droplet imaging in living cells and non-alcoholic fatty liver changes caused by bisphenol A. The fluorescent carbon dot is very simple to synthesize and purify, has the advantages of good light stability, large Stokes shift, high signal-to-noise ratio and the like, can quickly enter cells, and can naturally target lipid droplets.

The invention relates to a preparation method and application of a fluorescent probe used for identifying hydrogen peroxide and belongs to the technical field of chemical analysis and detection. The molecular structure of the fluorescent probe is described in the specification. Maximum absorption wavelength of the probe molecule is 480nm, after the probe molecule acts with hydrogen peroxide (H2O2), fluorescence spectrum emerges at the intensity of 619nm and is continuously increased, larger Stokes shifts are shown up, self absorption of fluorescent lights can be reduced, and detection sensitivity is improved; and emission wavelength can reduce background fluorescent lights and light damage on living cells in a probe detection process in a red light region, and penetrating power of an organism for tissues is enhanced. The probe molecule has good linearity in a certain time and concentration range, strong hydrogen peroxide (H2O2) identifying capability and strong selectivity and antijamming capability, and the probe has important application value in the fields of biochemistry and the like.

The invention discloses a fluorescent probe for detecting viscosity and hydrogen peroxide and a synthesis method and application of the probe, and belongs to the technical field of chemical analysis detection. The probe is obtained through a coupling reaction between aldehydic benzothiazole and a 4-methylpyridinium salt substituted by methylene phenylboronic acid. According to the structure of theprobe, due to the quenching effect of twisted intramolecular charge transfer (TICT), a probe molecule has almost no fluorescence emission characteristics. However, with the increase of the viscosityof an environmental system, the TICT effect is inhibited, and the probe molecule achieves strong fluorescence emission with the emission peak of 680 nm. In addition, the probe can also generate sensitive fluorescence response to H2O2, and the emission peak is 590 nm after the reaction. The concentration detection range of hydrogen peroxide is 0-25 Mumol L(-1), and the detection limit is 0.34 MumolL(-1). The probe can be used for detecting H2O2 in water and cells.

The invention provides a perylene excimer-based detection method for methylase activity and a screening method of a methylase inhibitor, and belongs to the field of biotechnology. The method comprises the following steps: firstly, preparing double-chain DNA, and then enabling the double-chain DNA to react with S-adenosylmethionine, restriction enzyme and different concentration of methylase, so as to obtain a mixed solution; enabling terminal deoxyribonucleotidyl transferase, deoxyribonucleoside triphosphate and TdT reaction buffer to react with the mixed solution, so as to obtain a reaction solution; finally, enabling the mixed solution of a perylene derivative probe and polycation to react with the reaction solution, and carrying out fluorescence detection on the methylase activity. The invention also provides a screening method of the methylase inhibitor. The activity of the methylase and the inhibitor is detected by using the change of ratio of a small molecule probe monomer to the excimer fluorescence intensity, the ratio of two given fluorescence signals is provided from the test, the fluorescence signals are not easily interfered in comparison with a pure fluorescence-intensified or weakened signal, and the sensitivity is higher.

Provided is a novel probe for a biological specimen for labelling by itself and clearly visualizing one of a specific cell and a specific cell organ in a living body, the probe having excellent spectral characteristics and exhibiting excellent storage stability. The probe for a biological specimen contains, as an active agent, at least one kind of compound represented by a general formula (I).

The present invention provides fluorescent dyes that are based on firefly luciferin structure. These dyes are optimally excited at shorter wavelengths and have Stokes shift of at least 50 nm. The fluorescent dyes of the invention are useful for preparation of dye-conjugates, which can be used in detection of an analyte in a sample.

The invention discloses a glutathione-protected strong-fluorescence-emission gold-platinum alloy nano-cluster and a controllable preparation method thereof, and belongs to the technical field of preparation of strong near-infrared light-emitting metal nano-cluster materials. A chloroauric acid trihydrate aqueous solution and a chloroplatinic acid hexahydrate aqueous solution are used as a gold source and a platinum source, sodium citrate is used as a reducing agent, and glutathione is used as a stabilizer and a ligand. The preparation method comprises the steps: uniformly mixing the chloroauric acid trihydrate aqueous solution and the chloroplatinic acid hexahydrate aqueous solution, adding a glutathione solution into the mixed solution, uniformly mixing, and adding a sodium citrate solution; and transferring the mixed solution into a reaction kettle, and carrying out hydrothermal reaction at the temperature of 100-120 DEG C for 30-210 min, and thus obtaining a glutathione-protected strong-fluorescence-emission gold-platinum alloy nano-cluster solution. Controllable preparation of the gold-platinum alloy nano-cluster with quite high stability for two different fluorescence emissions is realized by finely regulating and controlling experimental conditions such as reaction time, reaction temperature and a feeding ratio of reaction raw materials.