56results about How to "Enhanced fluorescence emission intensity" patented technology

The invention relates to a preparation method of a fluorescent biosensor of a double-cycle and double quenching system based on functionalized graphene quantum dots. The method comprises the followingsteps: weighing raw materials including citric acid, histidine and pentaethylene hexamine at the molar ratio of 0.01:0.1:1 to 1:1:1, uniformly mixing, adding deionized water, then performing ultrasonic dissolution to obtain a reaction solution, placing the reaction solution in an oven, reacting for 0.5-10h at an oven temperature of 150-250 DEG C to directly obtain a crude product of pentaethylenehexamine-histidine graphene quantum dot PEHA-GQD-His after reaction, then obtaining an LDNA-capped pentaethylene hexamine-histidine graphene quantum dot PEHA-GQD-His solution, finally forming a G-quadruplex / DNase, and finally adding 0.5-100[mu]l of H2O2 with the molar concentration of 0.1-10[mu]M to obtain the fluorescent biosensor of the double-cycle and double quenching system.

The invention discloses Er<3+> / Ce<3+> / Yb<3+> tri-doped tellurate glass containing silver nano particles and a preparation method thereof. The glass consists of the following components in percentage by mole: 65-75mol% of TeO2, 5-10mol% of Bi2O3, 10-20mol% of ZnO, 5-10mol% of Na2O, 0.1-1.0mol% of Er2O3, 0.1-1.0mol% of Ce2O3, 0.4-2.0mol% of Yb2O3 and 0.1-1.0mol% of AgNO3. The tellurate glass has the following advantages that by adopting tellurium oxide as a main component and adding bismuth oxide, zinc oxide and sodium oxide, the forming ability and physical-chemical stability of the glass are improved; due to the tri-doping way of rare earth Er<3+>, Ce<3+> and Yb<3+> ions, the sensitization among the rare earth ions is sufficiently utilized to improve the luminous efficiency of the rare earth Er<3+> ions under a commercial 980nm-wavelength semiconductor laser diode pump; and the fluorescence emission intensity of the doping Er<3+> ions in the 1.55mu m near infrared waveband is enhanced by the local field enhancement effect of the silver nano particles.

The invention belongs to the technical field of environmental science, and discloses an environmental micro-plastic labeled by metal organic fluorescent complex, and a preparation method and application of the environmental micro-plastic. The preparation method comprises the following steps: (a) dissolving a metal organic fluorescent complex by using an organic solvent to obtain a metal organic fluorescent complex solution, wherein the micro-plastic can be swelled through the organic solvent; and (b) soaking the micro-plastic in the metal organic fluorescent complex solution, and carrying outseparating and drying to obtain the environmental micro-plastic labeled by the metal organic fluorescent complex. The method provided by the invention is simple, the adjustability is strong, and the micro-plastic with different physical and chemical properties is easy to obtain; the generation of pseudo-fluorescent signals can be avoided through the environmental micro-plastic labeled by the metalorganic fluorescent complex; the interference of the spontaneous fluorescence background is less, and the detection accuracy is high; and the fluorescence emission intensity can be enhanced through the increase of the concentration, and the detection sensitivity of fluorescence imaging is improved. The environment micro-plastic provided by the invention is used for simulating the environmental exposure and health effect of environmental micro-plastic pollutants.

The invention provides a sulfide-based triple-doped electron trapping material and a preparation method thereof and relates to the technical fields of light emission and light storage. The invention solves the problems that the conventional Eu<2+> and Sm<3+> double rare earth doped sulfide system has low optical excitation luminous intensity and low light storage performance. The chemical formula of the electron trapping material is Sr1-x-y-zEuxSmyRezS, wherein the Re represents Er, Dy, Tm, Yb, Tb or Gd; x, y and z are the molar fraction of the elements; x is more than or equal to 0.0001 and less than or equal to 0.02; y is more than or equal to 0.0001 and less than or equal to 0.02; and z is more than or equal to 0.0001 and less than or equal to 0.006. The electronic storage quantity of the electron trapping material is increased by 1 to 4 times as compared with the electronic storage quantity of the sulfide Eu<2+> and Sm<3+> double-doped material; the optical excitation luminous intensity and the storage performance of the material can be effectively improved; and the commercial requirement can be met.

The invention discloses a method for preparing a polyolefin / rare earth complex / carbonate composite fluorescent material. The method is characterized in that by preparing a rare earth complex / carbonate compound and a polyolefin-organic solvent solution, the rare earth complex / carbonate compound and the polyolefin-organic solvent solution are mixed and reacted, after the reaction is completed, and a mixture is filtered and dried to obtain the polyolefin / rare earth complex / carbonate composite fluorescent material. The structure of the composite fluorescent material is a polyolefin-coated rare earth complex / carbonate compound, the fluorescence intensity is large, under same luminous intensity condition, the usage of rare earth elements is greatly reduced, and the production cost is reduced. The invention provides the method for preparing the polyolefin / rare earth complex / carbonate composite fluorescent material, the method is easy to operate, and the loss of the rare earth elements can be effectively avoided.

Disclosed are praseodymium-doped borophosphate base near-infrared ultra wide band luminescent glass and a preparation method thereof. The glass comprises 45-83 mol% of P2O5, 5-35 mol% of B2O3, 4-23 mol% of Al2O3, 6-22 mol% of Y2O3 and 0.1-3 mol% of Pr2O3. The preparation method of the glass includes the steps of raw material weighing, presintering, founding, pouring, annealing and the like. The preparation method is simple in process, high in ultra wide band near-infrared fluorescence-emission characteristic with emission wavelength of 830-1700nm and capable of improving the stability of the glass, reinforcing the luminous intensity of praseodymium ions, and satisfying the requirement of optical fiber wiredrawing.

The invention relates to a targeted mesoporous molecular imaging probe and a preparation method thereof. The targeted mesoporous molecular imaging probe comprises two parts including a surface plasma resonance core layer and a peripheral coating layer, wherein the surface plasma resonance core layer at least comprises a gold nanorod I, a gold nanorod II and substrate nano particles; the peripheral coating layer is formed by fluorescent molecules, sulfydryl small biological molecules and polystyrene sulfonate connectors; the gold nanorod I and the gold nanorod II are cohered on the substrate nano particles, so that the surface plasma resonance core layer can be formed; the distance between the gold nanorod I and the gold nanorod II meets the condition that d is more than or equal to (r1-r2) / 2 and less than or equal to (r1+r2) / 2; the exterior of the core layer is combined with the sulfydryl small biological molecules by a gold sulfhydryl bond, the fluorescent molecules are combined with the sulfydryl small biological molecules by an amide covalent bond, and polystyrene sulfonate is directly connected on a substrate in a bridging way. The invention also provides the preparation method of the targeted mesoporous molecular imaging probe. Blue shift or red shift is generated by surface excitation, and the characteristics of luminescence of a fluorescent structure are matched, so that the brightness is increased by 8-10 orders of magnitude. The targeted mesoporous molecular imaging probe has very high fluorescence characteristic, thus being applied to the diagnosis of tumor fluorescence imaging; the targeted mesoporous molecular imaging probe is especially suitable for detection and diagnosis of tumors in the dark field at the deep part of tissue cells.

The invention discloses bifunctional graphene quantum dots, and a preparation method and an application thereof, and belongs to the technical field of biosensors. The preparation method comprises thesteps: according to the molar ratio of citric acid to histidine to D-penicillamine of 1:0.1:0.01-1:1:1, preparing the dual-functionalized graphene quantum dots DPA-GQD-His by a hydrothermal method. The bifunctional graphene quantum dots provided by the invention can quantitatively detect one or more organophosphorus pesticides with high sensitivity and high selectivity, and the preparation methodis simple and easy to popularize.

The invention provides a double-ligand rare earth composite fluorescent material and a preparation method thereof, wherein a terbium double-ligand rare earth cooperation compound is prepared by changing the ratio of a first ligand acetylacetone to a second ligand 1,10-phenanthroline, and is tested or characterized, wherein the fluorescence emission intensity can reach 1149948 CPS, and the quantumyield can reach 24.98%. The method has a certain guiding significance in the later selection of organic ligands beneficial to Tb<3+> characteristic emission and synthesis of photoluminescence and electroluminescence materials with excellent performances.

The invention discloses bifunctional graphene quantum dots, and a preparation method and an application thereof, and belongs to the technical field of biosensors. The preparation method comprises thesteps: according to the molar ratio of citric acid to histidine to D-penicillamine of 1:0.1:0.01-1:1:1, preparing the dual-functionalized graphene quantum dots DPA-GQD-His by a hydrothermal method. The bifunctional graphene quantum dots provided by the invention can quantitatively detect one or more organophosphorus pesticides with high sensitivity and high selectivity, and the preparation methodis simple and easy to popularize.

The invention discloses a fluorescent probe for detecting viscosity. Its structural formula is as follows: it has long-wave emission performance and large Stokes shift characteristics, so that the overlap between absorption and emission spectra is small, and the fluorescence efficiency caused by energy transfer can be avoided. Reduce and improve detection sensitivity; it can have a strong penetration depth in the process of imaging biological systems, and can effectively eliminate the interference of cell autofluorescence, low toxicity to cells, and has broad application prospects in the field of biomolecular detection . The invention also provides a preparation method and application of a fluorescent probe for detecting viscosity, and the fluorescent probe for detecting viscosity can be used for viscosity measurement in a solution system or a biological system.

The invention provides a rare earth composite fluorescent material taking carbonate as a matrix and a preparation method of the rare earth composite fluorescent material. According to the preparationmethod, europium ions are used as a luminous body; triphenyl phosphine oxide (TPPO) and 2-thiophenyltrifluoroacetone (TTA) are taken as organic ligands; calcium carbonate is taken as a matrix; an europium complex composite fluorescent material is prepared under set conditions, and the obtained composite fluorescent material is characterized. The cost of the fluorescent material is reduced, and theprepared material is long in service life, high in quantum yield, high in fluorescence intensity and good in fluorescence performance.