65results about How to "High fluorescence stability" patented technology

The invention relates to a preparation method of a europium-doped carbon quantum dot composite material. The preparation method comprises the following steps: preparing a compound of citric acid and europium, and preparing the europium-doped carbon quantum dot composite material by adopting a hydrothermal method. The preparation method provided by the invention has the following beneficial effects: the method is simple and practical, the europium-doped carbon quantum dot composite material is endowed with the characteristics of high fluorescence stability, small size and good biocompatibility without being subjected to secondary modification, and the europium-doped carbon quantum dot composite material is improved in fluorescence properties significantly and can be excited by near ultraviolet to emit the characteristic red light of europium.

The invention discloses a preparation method of a composite material. The preparation method comprises the following step: carrying out melt extrusion on a mixture containing a polymer matrix and a perovskite precursor to obtain the composite material. The method for in-situ preparation of the perovskite quantum dot / polymer composite material by an extrusion process in the invention realizes the in-situ generation of perovskite quantum dots in a polymer matrix during extrusion processing, the obtained composite material may have multiple forms, and the in-situ generated perovskite quantum dotshave the characteristics of high fluorescence quantum yield, good stability and adjustable light-emitting wavelength, and can be applied to the fields of backlight display and the like.

The invention provides a polythymine template, a fluorescent copper nano-cluster based on the same, a preparation method of the fluorescent copper nano-cluster and an ATP detection method. The polythymine template has a single-chain DNA sequence and comprises at least one polythymine sequence which is (T)n, wherein n refers to natural number ranging from 15 to 40. The polythymine template can be used for preparing the fluorescent copper nano-cluster, preparation cost is low, and operation is simple and convenient. The ATP detection method is low in cost, simple and easy-to-implement in detection step, obvious in phenomenon, easy for observation and capable of quickly detection concentration of ATP in a sample in a high-sensitivity manner.

The invention discloses a method for preparing water-soluble carbon quantum dots from sisal hemp as a raw material. The method comprises the following steps: 1) pretreating the sisal hemp; 2) mixing deionized water and glycerol in a volume ratio of (2-5): 1 to obtain a mixed solution for standby application; 3) adding the pre-treated sisal hemp to the mixed solution obtained in the step 2), stirring the mixture, and placing the mixture in a microwave environment for microwave processing to obtain a brown solution; 4) filtering the brown solution to obtain a filtrate; 5) dialyzing the filtrate; 6) evaporating a dialysate at constant temperature to obtain the water-soluble carbon quantum dots. The water-soluble carbon quantum dots are prepared with a microwave method directly, the carbon source is rich and cheap, recovery of waste is facilitated, the preparation process is simple, the whole preparation process is non-polluting, non-toxic, green and environment-friendly, and large-scale preparation can be realized.

An immunization grouping analysis and detection method based on quantum point belongs to the nano-material field, comprises the following steps: (1) dispersing quantum points into borate buffer solution, adding sulfurated diimine and second antibody, mixing, reacting, centrifugating, washing, and obtaining second antibody compound with quantum point marks; wherein, the mole ratio of the quantum points, the sulfurated diimine and the second antibody is: 60: 15: 1; or (2) dispersing the quantum points into phosphoric acid buffer solution containing 1.25 % of glutaraldehyde by volume fraction, dispersing, reacting, adding second antibody, reacting, centrifugating, washing, and obtaining second antibody compound with quantum point marks; wherein, the mole ratio of the quantum points, the glutaraldehyde and the second antibody is: 60: 15: 1; then performing immunization reaction and observation according to the standard immunization grouping detection method. The method in the invention performs observation and judgement directly by fluorescence microscope, is simple and easy, can increase the fluorescence stability, and improve analysis accuracy and detection sensitivity.

The invention discloses a high-brightness stable perovskite magneto-optical microsphere for CTC capture. The preparation method comprises the following steps: by taking polystyrene porous spheres as shells, uniformly encapsulating Fe3O4 magnetic particles and MAPbBr3 quantum dots in the shells by utilizing a self-assembly method, and coating SiO2 shell layers on the surfaces of the shells to successfully construct (MAPbBr3 / Fe3O4)-coated MPSs-coated SiO2 magneto-optical microspheres; through surface modification, connecting a biological specific antibody SA and anti-EpCAM, and specifically capturing and identifying circulating tumor cells (CTCs), wherein perovskite quantum dots selected by the magneto-optical microspheres have high green fluorescence emission and high fluorescence quantum yield; and packaging the porous polystyrene microspheres and coating a silicon shell layer with the porous polystyrene microspheres. Compared with the prior art, the fluorescence stability of the magneto-optical microspheres is remarkably improved, direct contact between the MAPbBr3 quantum dot and a monitoring target object is avoided, the toxicity problem of heavy metal Pb in the biological monitoring process is solved, safety and no toxicity are achieved, and application in biomedicine is well developed. The preparation method disclosed by the invention has the advantages of mild reaction conditions, simple preparation process, short consumed time and relatively low cost.

The invention relates to a preparing method for carbon quantum dots free of cytotoxicity without protection gas. The preparing method comprises the steps that sodium glutamate is calcinated at a high temperature, and carbon dot powder is obtained; carbon dots are dissolved, subjected to ultrasonic oscillation, filtered and dried; a dried product is dissolved and dialyzed, and the carbon quantum dots are obtained. The preparing method is easy and convenient to operate, free of protection of protection gas, free of high-pressure conditions and environmentally friendly, and industrial production is easy. The carbon quantum dots prepared through the method have the advantages of being free of cytotoxicity, good in biocompatibility, high in quantum efficiency, excellent in fluorescence property (fluorescence stability, dark blink and an excellent pH property), uniform in particle size distribution, good in monodispersity and the like.

The invention provides a fluorescence angiography material and a preparation method and application thereof. The fluorescence angiography material is prepared by combining flavonoid fluorescent dye having a high fluorescence quantum yield and a hydrophobic cavity in a high-biocompatibility protein, wherein a structural formula of the flavonoid fluorescent dye is shown in the description; R1, R2, R3, R4, R5 and R6 are different substituents; R1, R2, R3 and R4 are H, hydroxy(-OH), hydroxymethyl(-OCH3) or dimethylamino(-N(CH3)2); R5 and R6 are methyl(-CH3), ethyl(-CH2CH3), butyl(-CH2CH2CH2CH3) or hydroxybutyl(-CH2CH2CH2CH2OH). The fluorescence angiography material has the characteristics of low biological toxicity, high fluorescence quantum yield, high fluorescent stability, high water solubility and high biocompatibility.

The invention provides a fusion protein gold nano-cluster complex Au@(gCTX)NCs and a preparation method and an application thereof. The technical scheme provided by the invention comprises that a recombinant chlorotoxin protein GST-CTX(gCTX) having a glioma targeting function is used as a template, and the multifunctional chlorotoxin-gold nano-cluster fluorescence complex is synthesized; at the same time, the invention relates to a preparation method of a protein gold nano-cluster complex, and also relates to the tumor targeting specificity of the chlorotoxin-gold nano-cluster fluorescence complex and use of the chlorotoxin-gold nano-cluster fluorescence complex in tumor diagnosis and treatment.

The invention discloses fluorescent conjugated polyelectrolyte with a plurality of carboxyl functional groups, and a preparation method. Polyphenylene ethynylene is used as a conjugated backbone; each repeating unit comprises fours carboxyl functional groups, and a plurality of carboxyl functional groups carried on the side chain thereof are easily coupled with biological molecules; and the polyelectrolyte has good biological compatibility, and is suitable for various biochemistry analysis experiments. The polycarboxyl fluorescent conjugated polyelectrolyte has the advantages of simple operation method, high water solubility and stable fluorescent characteristic. Compared with the other polyphenylene ethynylene polyelectrolyte, the polycarboxyl fluorescent conjugated polyelectrolyte solves the problem of poor solubility of the polymer, also has the advantages of good fluorescent characteristic, high biocompatibility and the like, is a fluorescent sensing material with high comprehensive performance, can be used for high-sensitivity detection of copper ions, and has high selectivity compared with the other materials. The polycarboxyl fluorescent conjugated polyelectrolyte has a structural formula shown in the specification.

The invention discloses preparation of near-infrared fluorescence nanoparticles and an application method of the near-infrared fluorescence nanoparticles in an imaging technology. A loaded near-infrared fluorescent dye is taken as a luminescence center, and chitosan and polylysine are taken as basic skeletons, so as to prepare the near-infrared fluorescence nanoparticles by self-assembling package of sodium alginate into a shell. A transmission electron microscope displays the mean grain sizes of the near-infrared fluorescence nanoparticles are about 15nm; a dynamic scattering test indicates that the mean dynamic hydration radius is less than 160nm; the photostability of the near-infrared fluorescence nanoparticles is significantly enhanced in comparison with fluorescent dye molecules; the near-infrared fluorescence nanoparticles can stably exist in 0-1.5% NaCl aqueous solution.

The invention relates to the technical field of heavy metal detection in the environment, and in particular relates to a method for detecting heavy meal based on fluorescence quenching of Cuibourtia SPP and an application thereof. The method comprises the following steps of 1, extracting fluorescent materials of the Cuibourtia SPP by using an extraction solvent; 2, preparing a heavy metal standardworking solution; 3, measuring a fluorescence spectrum curve of the heavy metal standard working solution by using a fluorescence spectrophotometer, and thus acquiring ratio fluorescence intensity values of two fluorescence characteristic peaks; 4, fitting corresponding heavy metal concentrations with the ratio fluorescence intensity values to acquire a fitting formula; and 5, mixing a target including heavy metal with Cuibourtia SPP extracting solution, measuring the ratio fluorescence intensity value of the target by using the fluorescence spectrophotometer, putting the ratio fluorescence intensity value into the fitting formula , and thus acquiring the heavy metal concentration in the target. According to the method and the application thereof provided by the invention, after the fluorescent materials of the Cuibourtia SPP are effectively extracted, the accuracy of the heavy metal detection is significantly improved; the method provided by the invention is low in cost, simple in technology, quick to detect, and relatively high in economic benefit.

The invention discloses a perovskite material with stable bipolar molecules and a photoelectric device, and belongs to the field of photoelectric materials and technologies. The invention aims to provide a perovskite material with stable bipolar molecules and a photoelectric device, which can indirectly enhance the interaction between metal cations and halogen anions, reduce the defect state density in the perovskite material and inhibit ion migration in the perovskite material by utilizing bipolar groups in a bipolar molecule stabilizer. The component of the perovskite material with stable bipolar molecules is D: A '2An-1BnX3n + 1 (n = 1, 2, 3) or D: ABX3, wherein A' is an organic amine cation, A is a monovalent cation, B is a metal cation, X is a monovalent anion, and D is a bipolar molecule stabilizer. The thermal stability, phase stability and fluorescence stability of the material are remarkably enhanced, and the working stability and efficiency of the perovskite material and a photoelectric device are remarkably improved.