169results about How to "Excellent fluorescence properties" patented technology

The invention discloses porous graphene and a graphene quantum dot. The porous graphene comprises, but is not limited to 2-9 atomic layers, wherein each atomic layer simultaneously comprises crystal lattices and holes of graphene, but is not limited to the holes of which the apertures are 2-10nm; the area of the holes accounts for about 5%-40% of total area of each atomic layer. The graphene quantum dot is characterized by comprising 1-5 atomic layers; the boundary is in a sawtooth shape; and the dimension of the quantum dot is 2-10nm. The porous graphene disclosed by the invention is uniform in aperture distribution, and not equal in interlayer spacing; and the graphene quantum dot has the advantages of high luminous efficacy, good crystal form and few defects.

The invention belongs to the technical field of quantum dot preparation, and specifically to a method for preparing copper-indium-sulfur (CuInS2) three-element quantum dots under a hydro-thermal condition. According to the method, common metal salt compounds such as copper chloride and indium chloride, and a sulfhydryl-containing carboxylic acid such as mercaptopropionic acid and mercaptosuccinic acid are adopted to synthesize copper-indium-sulfur (CuInS2) nanoparticles with the particle size of 2-4 nm and emission wavelength in the near infrared region under the hydro-thermal condition. Compared to other organic phase synthesis of the near infrared quantum dots, the method of the present invention has characteristics of less variety of the raw materials, cheap price, simple method, easy operation, good repeatability, and low requirements on equipment. Compared to the traditional quantum dots, the synthesized water-soluble quantum dots of the present invention have the following advantages that: the synthesized water-soluble quantum dots do not contain mercury, cadmium and other toxic metal elements, the emission peak is located in the near infrared region, the synthesized water-soluble quantum dots provide strong penetrabilities for cells and other biological tissues, and the synthesized water-soluble quantum dots can be widely used in immunological assays, nucleic acid hybridizations, gene analysis, cell classification and imaging and other fields.

The invention discloses a preparation method of a controlled fluorescent graphene quantum dot. The preparation method comprises the following steps: uniformly and quickly dispersing graphite oxide into ultrapure water by ultrasonic action to obtain a dispersion liquid of graphite oxide; adding different amount of hydrogen peroxide solution into the obtained dispersion liquid of graphite oxide, and at last, obtaining the graphene quantum dot under ultraviolet radiation. The preparation method disclosed by the invention is simple, and short in technology process; the prepared product is small in particle size, uniform in distribution, and excellent in fluorescent property; the conditions can be controlled to prepare the graphene quantum dot with the required wavelength.

The invention discloses a method for ultrasonically synthesizing hyperfluorescent carbon spots, and applications of the hyperfluorescent carbon spots, belonging to the field of nano-luminescence materials. The method comprises the following steps: (1) preparing a mixed solution by taking 0.1-5mol / L glucose as a carbon source, performing ultrasonic treatment to the mixed solution for 0.5-5h under the environment of pH ranging from 1 to 14; and (2) adding 0.1-5mol / L alcohol or amino acid into the mixed solution obtained in the step (1) as a modifier, and aging for 1-48h under the catalytic action of an inorganic salt catalyst, to obtain a hyperfluorescent carbon spots water solution. The method is simple to operate, pollution-free and mass production is easy to conduct.

The invention discloses a preparation method of carbon nanoparticles with controllable photoluminescence. In the method, the hydrothermal process is adopted; and the method comprises the following steps: preparing a solution composed of a carbohydrate which is used as a carbon source and an oxidation additive, feeding the solution to a hydrothermal reactor and heating to allow reactions; carrying out centrifugal separation on the reaction product, washing with water for three times and washing with ethanol for three times; removing salts; and drying to obtain carbon nanoparticles. The method provided by the invention is simple and low in cost. The prepared carbon nanoparticles have good dispersibility, contain abundant surface oxygen-containing groups (such as hydroxyl groups and carboxyl groups) which make surface functionalization or modification of carbon nanoparticles easier, and are excellent in fluorescence properties of ultraviolet-visible excited visible emission fluorescence properties, up-conversion fluorescence properties and near-infrared excitated near-infrared emission properties. The emission spectrum of carbon nanoparticles varies with the change in excitation wavelength.

The invention discloses a preparation method and application of a carbon dot / mesoporous silica composite material and belongs to the field of synthesis and application of fluorescent carbon nanomaterials and mesoporous composite materials. The method comprises the following steps: blending citric acid, ethanediamine, mesoporous silica and sodium nitrate into deionized water; carrying out ultrasonic dispersion and then putting in a reactor; carrying out normal pressure microplasma discharge processing; after discharging is ended, centrifugally separating, and washing and drying a solid to obtain the carbon dot / mesoporous silica composite material. The composite material is used for aspects of uranyl ion adsorption and adsorption process monitoring. The method has the advantages of quickness, simplicity and low energy consumption; the prepared carbon dot / mesoporous silica composite material has good fluorescent property and porous structure, and good adsorptive property to uranyl ions; in addition, the fluorescent property of the composite material is used for monitoring the adsorption process, and the visualization of the adsorption process is realized.

The invention discloses a preparation method for carbon quantum dots having controllable electroluminescent and photoluminescent performances. The preparation method includes the steps of: regulating the pH of a sucrose water solution to alkaline with sucrose as a carbon source, inserting a working electrode, intensively stirring the solution, and applying a voltage to carry out a reaction to obtain a product solution; collecting the product solution and separating out salts to obtain a carbon quantum dot solution; vacuum freeze-drying the carbon quantum dot solution to obtain a powdery solid, which is the carbon quantum dots having the controllable electroluminescent and photoluminescent performances. The method is carried out in a water solution system with the sucrose as a carbon source in an electrochemical manner, wherein different surface passivators are added to the reaction system to control the electroluminescent and fluorescent performances of the carbon quantum dots; in addition, the carbon quantum dots having excellent electroluminescent and fluorescent properties can be obtained without complex subsequent modification treatment, so that the carbon quantum dots has great application value in the fields of fluorescence and electroluminescence, and also has excellent application prospect.

The invention relates to a preparation method rhodamine hybridized carbon dots and application of the rhodamine hybridized carbon dots in mitochondrion target recognition. The preparation method disclosed by the invention has the beneficial effects that a microwave assisted method is utilized, citric acid and an m-amino phenol compound are used as raw materials, fluorescence emission wavelength can be regulated and controlled through a way of changing an amino group in a meta position of phenol, rhodamine molecular fluorogen hybridized carbon dots are generated, and preparation of controllableand divinable fluorescence emission wavelength carbon dots is realized. The preparation method disclosed by the invention is simple in operation, can easily obtain the raw materials and is green andenvironment-friendly, and a new strategy for synthesizing molecular fluorogen hybridized carbon dots is created. The rhodamine hybridized carbon dots prepared by the invention can be used for the mitochondrion target recognition in cells, and has potential application value in the fields of biology, medical treatment and the like.

The invention discloses a method for preparing a water-soluble fluorescent silicon nanoparticle by utilizing microwave radiation. The method comprises the steps of: mixing silicon source with trisodium citrate, disodium citrate, citric acid, glutaric acid or butanedioic acid to obtain a precursor solution, putting the precursor solution into a special glass tube for the microwave radiation, and carrying out the microwave radiation in a microwave reactor, so as to prepare the water-soluble fluorescent silicon nanoparticle. The method disclosed by the invention is completely carried out in an aqueous phase and has the advantages that the operation is safe, fast, simple and convenient, the toxin is low, and the raw material is safe and easily available; and the obtained water-soluble fluorescent silicon nanoparticle has excellent monodispersity and fluorescent property, high quantum yield and good stability and water solubility and can be taken as a fluorescent maker to be widely applied to biological detection and analysis.

The invention and belongs to the technical field of fluorescent nanomaterials, aims to solve the problems of relatively low yield of the current fluorescent carbon quantum dots, poor sensitivity of recognition response and anti-interference ability, a complicated reaction condition and the like, and provides a preparation method and application of fluorescent carbon quantum dots. With corn and dimethylene triamine DETA as raw materials, the fluorescent carbon quantum dots are synthesized in one step by a microwave heating method. The raw materials are cheap and easy to obtain; the carbon pointpreparation process method is simple and environmentally friendly; the fluorescent carbon quantum dots can be synthesized in large quantities; the fluorescent carbon quantum dots have small particlesizes of 3-5nm and uniform sizes, and can be stably dispersed in water, without an agglomeration phenomenon; the fluorescent carbon quantum dots have excellent fluorescence properties and relatively high fluorescent quantum yield; the fluorescent carbon quantum dots have excellent stability, and has stable performance under different ion concentrations, pH values and light irradiation time; the fluorescent carbon quantum dots have high selectivity, good reproducibility and high sensitivity during Cr (VI) and AA detection, and can quickly and accurately detect the contents of Cr (VI) and AA inliquid to be detected.

The invention relates to a human intestinal tract carboxylesterase activity detection fluorescent probe substrate and a use thereof and belongs to the technical field of medicine. The specific probe substrate is an aromatic ester (TCFE) of (E)-2-(4-(4-hydroxystyryl)-3-cyano-5, 5-dimethylfuran-2(5H)-ylidene)malononitrile (TCF). The substrate can be used for fast quantitative detection of human intestinal tract carboxylesterase activity and fast screening and assessment of a human intestinal tract carboxylesterase inhibitor. The fast quantitative determination process of human intestinal tract carboxylesterase activity comprises selecting a TCFE hydrolysis reaction as a probe reaction, adding an appropriate substrate into a buffer system containing hCE2, and determining real activity of hCE2 enzyme in various external biological samples through quantitative determination of a hydrolysis metabolite TCF generation amount in unit time in a linear reaction zone. The probe has good selectivity and the hydrolysate TCF has long fluorescence emission wavelength of 612nm. The human intestinal tract carboxylesterase activity detection fluorescent probe substrate can reduce biological sample background fluorescence and improve sensitivity and has good practicality and application prospect.

A process for preparing the water-soluble quantum site biofunctionalized by saccharide features that the saccharide with chelating biofunction is used as modifier and the quantum site is changed from oil-soluble one to water-soluble one by grinding white is biofunctionalized by saccharide.