74results about How to "High fluorescence yield" patented technology

The invention discloses a near-infrared silver sulphide quantum dot as well as a preparation method and application thereof. The silver sulphide quantum dot has a monoclinic phase structure, the particle diameter of the silver sulphide quantum dot is below 8nm, and the surface of the silver sulphide quantum dot can be connected and modified with a hydrophilic group of hydrophilic reagent containing sulfydryl. The preparation method comprises the following steps: fully reacting a mixed reaction system containing silver source and long-chain mercaptan in a sealed environment; cooling the mixed reaction system, and then adding a polar solvent; carrying out centrifugation and wshing to obtain a hydrophobic near-infrared silver sulphide quantum dot; fully mixing the hydrophobic near-infrared silver sulphide quantum dot and hydrophilic reagent containing sulfydryl in organic solvent to react; and carrying out centrifugation and washing the reacting mixture to obtain the biocompatibility near-infrared silver sulphide quantum dot. The quantum dot disclosed by the invention has the advantages of high fluorescence yield, good fluorescence stability, good biocompatibility and even size, and can be used for biological tissue imaging; and the preparation technology has moderate condition, short period and good repeatability, is simple to operate and is easy to control.

The invention relates to unsaturated dipyrromethene-boron borocarbons of formula (I) and the use thereof for fluorescence or electroluminescent analysis. The fluorescent properties are provided by the central ring of six atoms comprising the —N—B—N— sequence, R¹ to R⁷ permitting the modification of the compound properties (fluorescence emission wavelength, quantitative fluorescent yield), at least one of the substituents S¹ and S² has a chromophore end group which permits an excitation of the molecule at wavelengths close to those of the substituent chromophore. A preferably selected from the chromophore substituents with a wavelength close to the ultraviolet which significantly increases the Stokes displacement.

The characteristics of the phosphor ZnS:Ag,Cl which has a considerably high fluorescence yield in response to incident particles thus allowing for their easy detection are used as such and combined with the finding that the fluorescence components in the range of shorter wavelengths are short-lived, which led to an improvement of counting characteristics, hence allowing for high-rate measurements of particles. When B370 was used as an optical filter to pick up fluorescence components shorter than 450 nm, the decay time of short-lived fluorescence components could be reduced from 370 ns to 200 ns.

The present invention relates to a dinaphthyl ethylene derivative of formula (I), a process for preparing it, a film prepared from it useful in the manufacure of an organic light emitting device (OLED), an OLED including the film, and the use of the dinaphthyl ethylene derivative in the manufacture of an OLED.

Wherein R₁ to R₁₆ are defined as in the specification.

The invention belongs to the technical field of nanomaterials and relates to an electrochemical preparation method of nitrogen-doped fluorescent carbon dots (NC-dots) with up-conversion and down-conversion functions. The method comprises the steps of by taking an organic solvent as a carbon source, taking an alkaline substance and the organic solvent as electrolytes and taking platinum sheets as a positive electrode and a negative electrode, setting the electrolysis potential to 2.0-30.0 volt in a constant-potential mode, and carrying out electrochemical carbonization on organic matters for 2-5 hours, thereby obtaining a reaction solution; collecting a product solution, neutralizing, standing, and precipitating, thereby obtaining a supernatant; adding alcohol to precipitate salts, so as to obtain a NC-dots alcoholic solution; evaporating and concentrating the NC-dots alcoholic solution, and dialyzing, thereby obtaining a NC-dots aqueous solution. The method has the advantages that the simplicity and convenience in NC-dots synthesis are realized, the NC-dots with monodispersity and uniform particle diameter are obtained, and the obtained NC-dots have higher fluorescence yield (QY= 26.8%) and have good up-converted and down-converted fluorescence.

The invention discloses preparation and application of a titanium dioxide composite photocatalytic system. A preparation method comprises the steps of (1) nanometer gold preparation; (2) nanometer gold-carbon quantum dot preparation; (3) nanometer gold-carbon quantum dot-titanium dioxide composite system preparation. Visible light is used for performing photocatalytic performance test on the prepared composite material; the excellent photocatalytic performance of the material is proved by degrading organic pollutants of nonyl phenol. By starting from the angle of the composite material, the nanometer gold-carbon quantum dots are used as a titanium dioxide sensitizer; in visible light, after the photolytic activity sensitizer absorbs energy, free electrons are excited out; the electrons aretransferred onto a conduction band of titanium dioxide and then take a reduction reaction with organic matters; a good degradation effect is achieved. Nontoxic and harmless carbon quantum dots are used for modifying the titanium dioxide; a titanium dioxide visible light photocatalytic system is built; the absorption capacity and the catalytic activity of the system are improved; the degradation efficiency on pollutants is enhanced.

The invention provides a 2,1,3-Benzothiadiazole-based D-A-A type near-infrared luminous compound and application thereof. The chemical structure of the 2,1,3-Benzothiadiazole-based D-A-A type near-infrared luminous compound is described in the description, wherein 2,1,3-Benzothiadiazole is taken as a main body, A is cyano, pyridine, sulfuryl or bis(2,4,6-trimethylphenyl) borane; D is diphenylamine, triphenylamine, 4,4'-dimethyl diphenylamine, 4,4'-dimethyl triphenylamine, 4,4'-dimethoxy diphenylamine or 4,4'-dimethoxy triphenylamine. The D-A-A type near-infrared luminous compound provided by the invention not only maintains the intense interaction of D-A, but also has higher fluorescence quantum yield. The luminescent spectrum and quantum yield of the luminous compound can be adjusted by adjusting the intensity of the D-A, so that the balance of the D-A is realized, and the efficiency of a near-infrared organic light emitting diode is further increased.

The invention provides a synthesis method of high-fluorescence-efficiency Mn doping Cs2AgInCl6, and belongs to the technical field of semiconductor nanometer material preparation. According to the method, firstly, cesium chloride, silver chloride and indium chloride are mixed; then, grinding is performed; the mixture gradually becomes hard from puff white powder to be attached onto a container wall and then becomes soft; continuous grinding is performed until the mixture becomes the puff white powder again; next, manganese chloride is added; continuous grinding is performed until the pink ultra-dry manganese chloride is uniformly dispersed into a reaction system; when the pink color disappears, the grinding is stopped; the obtained product is cleaned by ethanol, and then dried for 2 hoursunder the vacuum conditions of 60 to 350 DEG C; high-fluorescence-efficiency Mn<2+> Cs2AgInCl6 is obtained. The synthesis method has the advantages that the operation is simple; the method is simple;the fluorescence quantum yield is high; the industrialized production can be easily realized, and the like.

The invention relates to a bis-heterocyclic triazene compound, and specifically relates to a 2,2'-bis(2-hydroxy-4-sulfonic-1-naphthylamine azoxyl)-5,5'-dimethyl-4,4'-bithiazole and a preparation method thereof. The preparation method comprises the following steps of: (1) preparation of 2,5-dibromohexanedione; (2) preparation of 2,2'-diamino-5,5'-dimethyl-4,4'-bithiazole; (3) preparation of 5,5'-dimethyl-4,4'-bithiazole-2,2'- bis-diazonium salt; (4) preparation of an objective product BHSNAADMBT. The technical scheme of the invention connects bithiazole heterocycle and naphthalene ring derivative with fluorescence property together to synthesize a reagent with double functional-analytical groups and large steric hindrance; and the compound of the invention not only has high reaction sensitivity with metal ions, but also has good selectivity. The reagent is a good photometric analysis developer and a novel fluorescence analytical reagent with high sensitivity and good selectivity as well.

The invention discloses fluorescently labeled polysaccharide. The fluorescently labeled polysaccharide is formed by covalently coupling polysaccharide to a fluorescent dye, and the fluorescent dye adopts the structure shown as a formula I in the specification. Polysaccharide molecules and fluorescent dye molecules form stable covalent bonds, so that the fluorescently labeled polysaccharide has high stability in serum and other detection environments, has high biocompatibility, and is suitable for detection of saccharide molecules inside and outside cells. Due to large Stokes shift of the fluorescent dye molecules, the fluorescently labeled polysaccharide also has the advantages of good fluorescent stability, high fluorescence quantum yield, and high signal-to-noise ratio of an imaging result. The invention discloses a preparation method of the fluorescently labeled polysaccharide. With the preparation method, a reaction condition is mild, the operation is simple, the reaction selectivity is high, and the fluorescently labeled polysaccharide with high yield can be prepared.

The invention relates to bis-triazene compound, in particular to a method for preparing 3, 3'-dihydroxy-4,4'-di(1,1'-dinaphthylamine azo group) azobenzene and application thereof. A molecular structural formula of the 3,3'-dihydroxy-4,4'-di(1,1'-dinaphthylamine azo group) azobenzene is shown as an illustration below. The method is characterized in that naphthylamine and 3,3'-dihydroxy-4,4'- dinaphthylamine azo group which have a fluorescent characteristic are combined together through a diazotization reaction and a coupling reaction, so that a conjugated system of the compound is increased to be a ditriazene reagent, and the fluorescent characteristic of the reagent is improved. The reagent is a fluorescent reagent which is high in sensitivity of detecting Ag (I) in an alkaline medium and good in selectivity. Therefore, the reagent is not only a good photometric analysis color reagent but also a fluorescent analysis reagent which is good in sensitivity and selectivity and low in detection limit, and can be used for detecting silver ions in the alkaline medium.

The present invention discloses a metal complex of a biscalix[4]arene derivative, having a chemical structure represented by formula II. The complex has a small toxicity and a high biocompatibility, is suitable for being covalently combined with nucleic acids, peptides, proteins or other biological molecules to form a fluorescent probe molecule having a high fluorescence quantum ratio, a long fluorescence lifetime and a low detection limit, is suitable for biomolecule detection in cells, tissues or living organisms, and has a broad application prospect in the field of biomedicines. The invention discloses a synthesis method of the complex. The method provides multiple selection routes for the synthesis of the complex, and has the advantages of simplicity and easiness in the synthesis routes, high yield in the obtained complex, and suitableness for large-scale production preparation of the complex.

The invention belongs to the field of nano-medicine and molecular imaging, and particularly relates to a fluorescent carbon dot for labeling of radionuclide iodine, a synthetic method of the fluorescent carbon dot and application in tumor imaging. The carbon dot is synthesized in one step and can be directly labeled with radionuclide iodine. A labeled product has excellent radiochemical stability and physicochemical stability and can be directly used for 124I-based PET (positron emission tomography), SPECT(125I-based single-photon emission computed tomography) imaging and 131I radiotherapy of a tumor region. The synthetic method of the fluorescent carbon dot is simple, price of raw materials is low, fluorescence efficiency is high, and biocompatibility is good; the fluorescent carbon dot has the advantage of rapid metabolism in vivo like small molecules, and can also be well enriched in the tumor region by effects of high permeability and long retention of nanoparticles to diagnose and treat a tumor.

The invention discloses a metal complex of a double-cup[4]aromatic hydrocarbon derivative. The metal complex has a chemical structure as shown in formula II. The complex is small in toxicity, high inbiological compatibility, suitable for being covalently combined with biological molecules such as nucleic acid, peptide or proteins to form a fluorescent probe molecule with high fluorescent quantumrate, long fluorescent service life and low detection limit, suitable for detecting the biological molecules in cells, tissues or living bodies and wide in application prospect in the field of biological medicine. The invention discloses a synthetic method of the complex, provides various selection ways for the synthesis of the complex, is simple and easy in synthesizing a route, high in yield ofprepared complex and suitable for the mass production of the complex.

The invention provides a preparation method of II-VI family water-soluble selenide semiconductor quantum dots, which comprises the following specific steps: adding a stabilizer into solution containing soluble cadmium salt, soluble zinc salt or soluble mercury salt, then regulating the pH value of the solution to be be alkaline, then introducing hydrogen selenide gas under inert atmosphere, and reacting till the solution is pale yellow and transparent, thereby preparing solution of a precursor, wherein the molar ratio of the soluble cadmium salt, the soluble zinc salt or the soluble mercury salt to the stabilizer is 1: 3-1: 2. High-temperature and high-pressure fast growth is performed on the solution of the precursor, thereby preparing the II-VI family water-soluble selenide semiconductor quantum dots. For the preparation method, the operation is simple, the cost is low, the toxicity is small, and the prepared II-VI family water-soluble selenide semiconductor quantum dots can be directly used for biological fluorescent marking, clinical diagnosis and other experiments.

The invention discloses a method for improving the fluorescence yield and the stability of a bi-based perovskite nano material and a product. The method comprises the following steps: introducing long chain amine and a chloride source into a precursor raw material required by preparation of a quantum dot MA3Bi2Br9, and by regulating and controlling the adding ratios of the long chain amine and the chloride source which are introduced, finally obtaining a product shaped like (MAxOLA1-x)3Bi2ClyBr9-y. According to the method, under the intercalation action of the long chain amine, the shape and the appearance of the product can be changed from the quantum dot into a nano sheet, so that the stronger exciton confinement effect is achieved, and the fluorescence quantum yield can be increased; by the use of the high bond energy of a bismuth-chloride bond, the stability of the quantum dot MA3Bi2Br9 is improved, and surface defects are passivated, therefore, the fluorescence quantum yield of the final product is increased. After the improvement on constituents and the structure of the quantum dot MA3Bi2Br9, compared with the prior art, the method has the advantage of effectively improving the fluorescence yield and the stability of the bi-based perovskite nano material.

The invention discloses a novel method for ultrasonically and electrochemically synthesizing a water-soluble CdTe quantum dot, belonging to the field of material synthesis and solves the problems of low yield and strict reaction condition in a traditional aqueous-phase synthesis method of the quantum dot. By utilizing an ultrasonic electrochemical method and controlling test parameters such as reaction pH, current size, current pulse time, ultrasonic time, reaction temperature and response time, the semiconductor quantum dot CdTe can be synthesized once without the N2 protection and the preparation of a precursor, so that the purposes that the grain size of a monodisperse quantum dot is controllable and the fluorescence-emission wavelength is continuously adjustable are achieved. The semiconductor quantum dot CdTe obtained by utilizing the method has the advantages that the fluorescence-emission wavelength range is 509nm-560nm, the maximal quantum dot yield is 36%, a possibility is provided for applying the ultrasonic electrochemistry to the synthesis of other quantum dots, and the method has important significances to the application of the fields of solar cells, photocatalysis and sensors.