80results about How to "Fluorescence stabilization" patented technology

A method of making a colloidal solution of ternary semiconductor nanocrystals, includes providing binary semiconductor cores; forming first shells on the binary semiconductor cores containing one of the components of the binary semiconductor cores and another component which when combined with the binary semiconductor will form a ternary semiconductor, thereby providing core / shell nanocrystals; and annealing the core / shell nanocrystals to form ternary semiconductor nanocrystals containing a gradient in alloy composition.

The invention relates to a preparation method of an Escherichia coli (E.coli) biosensor and a product obtained thereby. The preparation method comprises the following steps: (1) knocking out three genes, namely copA, cueO and cusA in a wild-type E.coli MC4100 genome by a Red recombination system; (2) constructing a fusion reporter gene PcopA::gfpmut2 by adopting a cross PCR (Polymerase Chain Reaction) technology; (3) cloning the segment obtained in step (2) to a pMD18-T vector; (4) carrying out double digestion on a PcopA::gfpmut2-T vector to obtain a target strip, and then connecting the target strip to a pET28a vector; and (5) converting a fusion reporter vector obtained in the step (4) to a deltacopA-deltacueO-deltacusA tri-gene mutant strain obtained in the step (1). In the preparation method, the three genes such as the copA, the cueO and the cusA are deleted from wild-type E.coli MC4100, and then the genes are converted to the fusion reporter vector PcopA::gfpmut2-pET28a so as to finally obtain the product. The product obtained by the method has the characteristics of high specificity, high sensitivity, high speed, high efficiency, high cost performance and the like, and is simple and convenient to use, thus being applicable to real-time field monitoring of copper ions.

The invention relates to a novel water-soluble sulfydryl fluorescent probe which is a 2-(2'-hydroxyphenyl) benzimidazole (HPBI) compound modified by quaternary ammonium salt. The compound has the structure of 2-[5-(trimethyl quaternary ammonium salt)-acetamido-2'-hydroxyphenyl) benzimidazole. The fluorescent probe can be used for detecting a biological sulfhydryl compound in aqueous solution and living tumor cell, i.e. the novel water-soluble sulfydryl fluorescent probe is selectively coordinated with cupric ions and an obtained coordination compound can enter the living cell to be reacted with the sulfhydryl compound, so that a fluorescent compound is changed into ionic molecules again and fluorescent light is recovered. The novel water-soluble sulfydryl fluorescent probe has the advantages that the novel water-soluble sulfydryl fluorescent probe has excellent water solubility and biocompatibility and high sulfhydryl measurement sensitivity; before and after GSH (glutathione) reaction, the fluorescent light is rapidly changed and is stable; the novel water-soluble sulfydryl fluorescent probe can be stored and used for a long time; and according to the fluorescent probe, a good research method is provided for researching a biological signal channel related to the biological sulfydryl and the significance and diagnosis of the sulfydryl in the in vivo process of diseases or organisms.

The invention provides a method for preparing a fluorescent polymer rare earth complex nano-microsphere. The method comprises the steps: allowing a monomer I to be subjected to miniemulsion polymerization to obtain a polymer seed microsphere emulsion I; adding a monomer II to the polymer seed microsphere emulsion I to be subjected to seed emulsion polymerization to obtain a core-shell nano-microsphere emulsion II; extracting core-shell nano-microspheres by high-speed centrifugation or freeze-drying of the core-shell nano-microsphere emulsion II to be dispersed in an organic solvent, and then adding a rare earth compound and a small molecule ligand to be subjected to a coordination reaction to obtain the solvent-resistant fluorescent polymer rare earth complex nano-microsphere. The prepared nano-microsphere has a uniform size, the preparation method is simple and practicable, high-intensity fluorescent lights of different colors can be obtained by adding different rare earth compounds, the environmental stability is particularly excellent, and the nano-microsphere still can be used after being stored for a year, can be stably dispersed in various organic solvents, and has good development prospects.

The invention discloses a preparation method of a water-soluble nitrogen-phosphorus-boron codoped carbon quantum dot. The preparation method comprises the following steps: step I, dissolving phenylphosphinic acid in ultra pure water to obtain a precursor solution I, dissolving 3-aminobenzene boronic acid in ultra pure water to obtain a precursor solution II, and uniformly mixing the precursor solution I with the precursor solution II in the volume ratio of the precursor solution I to the precursor solution II being (1-6) to 1 so as to obtain a mixed solution; step II, performing a hydrothermal reaction on the mixed solution prepared in the step I so as to obtain the water-soluble nitrogen-phosphorus-boron codoped carbon quantum dot. According to the preparation method disclosed by the invention, the water-soluble nitrogen-phosphorus-boron codoped carbon quantum dot is prepared by the one-step hydrothermal method, carbon sources are rich, a preparation process is simple and easy, the whole preparation process is pollution-free, non-toxic, green and environmentally-friendly, and the water-soluble nitrogen-phosphorus-boron codoped carbon quantum dot can be prepared in a large-scale manner.

The invention discloses a double sandwich immunoassay test kit labeled by HE4 quantum dots. The kit comprises HE4 protein standards, an ELISA plate coated with HE4 specific polyclonal antibodies, and CdTe quantum dots labeled monoclonal antibodies in specific binding with HE4 proteins. The invention further discloses an application of the kit in diagnosis of ovarian tumor. According to the invention, the test kit can directly determine test results through fluorescent ELISA, emitted fluorescence spectral peaks are narrow, autofluorescence is weak, and a sensitivity is high. The kit is high in fluorescence intensity and long in stable time, and can relatively effectively facilitate early detection and risk assessment of the ovarian tumor.

The present invention relates to a carboxyl functionalized micro-scale rod-like upconversion fluorescence material and a preparation method thereof, wherein a micro-scale upconversion fluorescence material is subjected to one-step synthesis through a hydrothermal method, different colors of the upconversion fluorescence materials having a length of about 1-2 [mu]m can be prepared, and the preparation process is simple and convenient. According to the present invention, during the synthesis process, the required raw materials are added to a mixed solvent of oleic acid and ethanol according to a certain ratio, reaction is performed for 8-12 h at a temperature of 180-200 DEG C, and the product is subjected to centrifugal washing so as to obtain the purified upconversion micrometer rod; the amino can be introduced onto the upconversion material surface through the classical method and the carboxyl functionalization is successfully achieved by adding PAA through the amide bond coupling so as to enhance the dispersity in the aqueous solution and provide a large number of the reactive sites for coupling biomolecules; and the prepared material has characteristics of low production cost, good fluorescence stability and easy surface modification, can be used for detection of biological macromolecules, and can further be widely used for rapid detection of antigens, nucleic acids and the like.

The invention relates to the field of immunochromatography detection, in particular to a fluorescence immunochromatography instrument quality control detection card, a detection kit, a preparation method and a detection method thereof. The quality control test card is on the PVC bottom plate, with a detection window, a nitrocellulose film is fixed in the detection window, and a Q C line and a Q T line, Q C Line and Q T Lines are drawn with fluorescent microsphere solution. Select at least 2 quality control test cards to form a quality control test kit. Calculate the Q of each quality control test card in turn T / Q C The area ratio is compared with the standard curve. When the error is higher than a certain value, it is judged that the reliability of the measurement result of the instrument is low. The invention is applied to the quality control detection of the fluorescence immunochromatography instrument, has simple and convenient operation, and can be applied to on-site detection; the instrument quality inspection is carried out before the sample is detected, which can improve the reliability of the sample measurement result.