2350 results about "Buffer solution" patented technology

The invention discloses an extraction and purification method and application of plant-derived exosome-like nanoparticles, and relates to the technical field of plant exosome preparation. The extraction and purification method comprises the following steps: washing fresh ginseng, airing for later use, adding a proper amount of buffer solution, mixing, breaking walls, filtering, centrifuging filtrate to obtain supernate, carrying out ultracentrifugation on the supernate to obtain ginseng exosome nano-particle precipitates, resuspending the precipitates, respectively adding pure water sucrose solutions with different concentrations, and carrying out ultracentrifugation to obtain ginseng exosome nano-particles; and re-suspending the target strip, and carrying out ultracentrifugation to remove redundant cane sugar so as to obtain the purified ginseng exosome-like nano-particles. The ginseng exosome-like nano-particles disclosed by the invention have a remarkable effect when being applied to cosmetics or medicines with skin photoaging resistance, skin oxidation resistance and wrinkle resistance. In an anti-UVB (Ultraviolet B) induced cell injury experiment, the ginseng exosome-like nano-particles have an excellent anti-UVB induced cell injury effect.

The invention discloses a preparation method of injectable nano composite hydrogel for relieving osteoarthritis, which comprises the following steps: firstly, synthesizing nano rod-like hydroxyapatite with the length of 150-300 nm and the diameter of 10-15 nm, and the hydroxyapatite is hydrophilic hydroxyapatite doped with strontium and europium ions; the preparation method comprises the following steps: by taking Ca (NO3) 2, Sr (NO3) 2, Eu (NO3) 3 and soluble phosphate as main raw materials, carrying out hydrothermal reaction to prepare strontium and europium ion co-doped hydrophobic hydroxyapatite, dispersing the strontium and europium ion co-doped hydrophobic hydroxyapatite in a Tris-HCl buffer solution, adding tannic acid, stirring, centrifugally collecting precipitate, and drying to obtain strontium and europium ion doped hydrophilic hydroxyapatite; the preparation method comprises the following steps: taking chondroitin sulfate and adipic dihydrazide as main raw materials, stirring, dialyzing, freeze-drying, and dissolving in a buffer solution to obtain the chondroitin sulfate solution grafted with the hydrazide group; the preparation method comprises the following steps: taking hyaluronic acid, 3-aminophenylboronic acid and sodium periodate as main raw materials, stirring, dialyzing, freeze-drying, and dissolving in a buffer solution to obtain the phenylboronic acid group grafted oxidized hyaluronic acid solution; the preparation method comprises the following steps: blending hydrophilic hydroxyapatite doped with strontium and europium ions, a chondroitin sulfate solution grafted with a hydrazide group, an oxidized hyaluronic acid solution grafted with a phenylboronic acid group and a recombinant collagen solution, and stirring to obtain the injectable nano composite hydrogel. The injectable nano composite hydrogel obtained by the invention has good biocompatibility, and a favorable local immune microenvironment can be created to immunomodulate macrophages so as to relieve osteoarthritis and promote subchondral bone repair.

The invention discloses a high temperature resistant xanthan gum lyase mutant and a preparation method thereof, wild type xanthan gum lyase comes from Paenibacillus anensis, site-directed mutagenesis is carried out on the wild type xanthan gum lyase to obtain the high temperature resistant xanthan gum lyase mutant, and the mutant comprises at least one of N66V, R292A and S676V. The enzymatic activity of the xanthan gum lyase mutant treated in a buffer solution with the pH value of 5.0 at the temperature of 65-85 DEG C for 2 h is remarkably improved compared with that of an original enzyme, and the enzymatic activity of N66V / R292A / S676V is improved by 3.8 times compared with that of the original enzyme at the temperature of 85 DEG C.

The invention relates to an enzyme reagent, glucose electrochemical test paper and a preparation method thereof, and belongs to the technical field of electrochemical detection. The glucose electrochemical test paper comprises an electrode substrate and an enzyme reagent arranged on the electrode substrate, the enzyme reagent is prepared from the following components in parts by mass: 5 to 7 parts of buffer solution, 0.01 to 0.2 part of hexamine ruthenium trichloride, 0.01 to 0.1 part of quinone compound, 0.1 to 1.2 parts of metal organic framework immobilized glucose dehydrogenase and 0.2 to 0.8 part of film-forming agent. According to the glucose electrochemical test paper, the detection accuracy of glucose can be improved, and the problems of large interference, small linear range, insensitive detection and the like in the prior art are improved or solved.

The utility model discloses a microfluidic system for target object pairing, which comprises a first flow channel, a second flow channel, an oil liquid flow channel, a buffer liquid flow channel, a matching flow channel and a pairing micro valve, a first micro valve, a second micro valve and a buffer liquid micro valve are arranged, the matching flow channel is communicated to the oil liquid flow channel, and the first flow channel, the second flow channel and the buffer liquid flow channel are all communicated to the matching flow channel; when a single first target object and a single second target object exist in the matching runner, the first micro valve and the second micro valve are in a closed state, and the matching micro valve and the buffer solution micro valve are in an open state; and the buffer liquid in the buffer liquid flow channel feeds the single first target object and the single second target object in the flow channel into the oil liquid in the oil liquid flow channel to form liquid drops. According to the utility model, other first target objects and / or other second target objects can be completely prevented from entering liquid drops, so that the success rate of packaging is improved, and the cell loss caused by multiple packaging is reduced.

The invention belongs to the technical field of creatine kinase detection kits, and particularly relates to a creatine kinase detection reagent, a creatine kinase detection kit and application, the creatine kinase detection reagent comprises a buffer solution, creatine phosphate, glycerol, glycerol kinase, glycerophosphate oxidase, peroxidase and a color developing agent, and further comprises a CK activation reducing agent and perfluoro and polyfluoroalkyl substances, the CK activation reducing agent is a sulfur-containing reducing agent. According to the method, the detection accuracy can be improved.

The invention discloses a non-specific peroxygenase mutant and application thereof and a preparation method of 25-hydroxyvitamin D3, and particularly relates to a protein obtained by taking an amino acid sequence as shown in SEQ ID NO.1 as a starting sequence and mutating amino acid residues as shown in the 20th site and / or the 25th site and / or the 57th site. The catalyst has relatively high catalytic activity and stereocatalysis specific selectivity; according to the method, acetone, vitamin D3, hydrogen peroxide and a non-specific peroxygenase mutant are respectively added into a potassium phosphate buffer solution with the pH value of 7.0-8.0 to form a reaction mixed solution, an oxidation reaction is carried out for 10-50 hours at the temperature of 25-35 DEG C, the 25-hydroxyvitamin D3 is generated, the reaction condition is mild, the reaction operation is simple and convenient, the conversion rate is high, the cost is low, the preparation efficiency of the 25-hydroxyvitamin D3 is greatly improved, and the method is suitable for industrial production. Good industrial application prospects are realized.

The invention relates to the technical field of drug analysis and detection, and provides a detection method of moxifloxacin hydrochloride related substances. The related substances of moxifloxacin hydrochloride are detected by adopting a high performance liquid chromatography method, and the detection conditions are as follows: octadecylsilane chemically bonded silica is taken as a filling agent of a chromatographic column; the wavelength of a UV detector is 296 nm; the column temperature is 35-45 DEG C; the flow velocity of the mobile phase is 1.6-1.8 ml / min; the sample injection volume is 10-50 [mu] l; the mobile phase A is phosphate buffer solution-acetonitrile-methanol; the mobile phase B is phosphate buffer solution-acetonitrile-methanol; the elution mode is gradient elution; the diluent is a mobile phase A; according to the method provided by the invention, effective separation between moxifloxacin hydrochloride and various impurities can be realized, the sensitivity is high, the accuracy is good, the reproducibility is relatively good, a good linear relation is shown in a certain range, and qualitative and quantitative determination can be carried out on various impurities in moxifloxacin hydrochloride bulk drugs.

The invention relates to the technical field of nucleic acid detection, and discloses a nucleic acid integrated detection device based on a flexible structure and a push-pull structure, which comprises a detection main body, an upper cover, a bottom shell and an extrusion block arranged between the upper cover and the bottom shell, the detection main body is arranged in an accommodating cavity between the upper cover and the bottom shell; the detection main body comprises a sample introduction tube, a nucleic acid extraction-free reagent chamber, a first buffer solution chamber, a nucleic acid amplification reagent chamber, a second buffer solution chamber, a uniform mixing chamber, a sample loading groove and chromatography test paper which are connected in sequence, wherein the nucleic acid extraction-free reagent chamber, the first buffer solution chamber, the nucleic acid amplification reagent chamber, the second buffer solution chamber and the uniform mixing chamber are flexible reagent chambers; the head end of the sample loading groove is connected with the uniform mixing chamber, and the tail end of the sample loading groove is connected with the chromatography test paper; and the extrusion block can move from one end of the upper cover to the other end and is used for extruding the liquid in the detection main body and forcing the liquid to flow downstream. The liquid is extruded to flow downstream only when the extrusion block is manually pushed to move, so that the controllability of the detection process can be realized.

The invention relates to the technical field of biological adhesives, in particular to a pH response type chitosan medical biological adhesive and a preparation and application method thereof.The preparation method includes the steps that phenylboronic acid modified chitosan, polyphenol compounds, cross-linking agents with different functional groups and polyethylene glycol with different molecular weights are evenly mixed in a PBS buffer solution with the pH equal to 7-8; and adjusting the pH value of the system to 7.5-8 by using a KOH aqueous solution, and standing at room temperature until the pH-responsive chitosan medical biological adhesive is formed. The chitosan biological adhesive disclosed by the invention still keeps excellent adhesive power in a moist environment, is rapid in adhesion, is non-toxic and biodegradable in material, has good biocompatibility, and effectively avoids secondary stitch removal pain caused by non-degradable materials. Due to the charge characteristic of the chitosan, the chitosan has good affinity with human tissues, is suitable for adhesion of various tissues, and has wide clinical application potential.

The invention relates to the technical field of hydrogel, in particular to a preparation method and application of EGCG-mediated hydrogel, a lysozyme solution is heated under the acidic condition to form lysozyme amyloid fibrils LAFs, EGCG is dissolved in a buffer solution and mixed with the LAFs solution obtained in the step 1 in proportion to form an LAFs-EGCG compound, and the EGCG-mediated hydrogel is prepared. The chitosan CS is dissolved in an acetic acid buffer solution, glutaraldehyde is added to serve as a cross-linking agent, the mixture is mixed with the LAFs-EGCG compound obtained in the step 2 and stirred, the composite hydrogel is formed, the concentration of EGCG is 0.2-1.0 wt%, the concentration of LAFs is 5 wt%, the concentration of chitosan is 2 wt%, the pH value of the lysozyme solution in the step 1 is 2.0, the heating temperature is 77 DEG C, the heating time is 10 hours, the concentration of EGCG in the step 2 is 0.4-0.8 wt%, and the pH value of the lysozyme solution in the step 2 is 1.5-2.5. In the step 3, the concentration of glutaraldehyde is 2%, the storage modulus G'of the hydrogel is 325-480 Pa, the hardness is 2176.71 g, and the bacteriostasis rate on staphylococcus aureus and salmonella exceeds 95%.

The invention belongs to the technical field of medicine detection, and particularly relates to a high-sensitivity liquid chromatography method for detecting mutagenic impurities in atomoxetine hydrochloride key starting material 3-chlorobenzene propanol, the method adopts an HPLC (High Performance Liquid Chromatography) analysis method, a chromatographic column adopts octadecylsilane chemically bonded silica as a filler, and the composition of a mobile phase A is a buffer solution; the mobile phase B is methanol or acetonitrile; carrying out gradient elution on the mobile phase; the flow velocity is 0.4 to 0.8 ml / min; the detection wavelength is 230 to 250 nm; by adopting an HPLC analysis method, the content of mutagenic impurities in the key starting material 3-chlorobenzene propanol of atomoxetine hydrochloride can be effectively separated and measured, and the method is high in sensitivity, strong in specificity and good in accuracy and repeatability, and has extremely important significance on quality control of the key starting material 3-chlorobenzene propanol of atomoxetine hydrochloride.

The invention relates to the technical field of polymer gels, and provides a multi-crosslinking composite gel and a preparation method and application thereof, the preparation method comprises the following steps: fully dissolving an activator in a buffer solution, and adjusting the pH value of the solution to 5.0-6.0 to obtain an activated solution; sequentially adding recombinant III-type humanized collagen, polydeoxyribonucleotide and chitosan into the activated solution, and uniformly dispersing to obtain a cross-linked precursor solution; adding a cross-linking agent into the cross-linking precursor solution, reacting for a period of time to obtain a cross-linking gel intermediate, and purifying to obtain the multi-cross-linking composite gel; the invention also provides the multi-crosslinking composite gel prepared by the preparation method, and application of the multi-crosslinking composite gel in the fields of beauty and plastic surgery. The material has biodegradability and good antibacterial performance, and can ensure slow release of the material and good filling effect and anti-enzymolysis effect at the same time.

The invention relates to the field of enzyme preparations, and discloses an enzyme preparation for catalytic degradation of bioplastics and a preparation method thereof, the enzyme preparation for catalytic degradation of bioplastics comprises the following components by weight: 25-50 parts of an enzyme, 1-8 parts of a catalytic additive, 2-10 parts of a stable dispersant, and 30-50 parts of a buffer solution; the catalytic additive is prepared by using calcium bentonite as a carrier to load nano titanium dioxide; the stabilizing dispersant is prepared by introducing polyethylene glycol monoallyl ether into a sodium lignin sulfonate structure by utilizing an initiator through an aqueous solution polymerization method, and by adding the catalytic additive and the stabilizing dispersant, the enzyme preparation is endowed with good degradation efficiency on bio-based plastics and the stability of an enzyme preparation system is improved.

The invention provides a preparation method of a Janus material for simultaneous screening of protein phosphorylation and palmitoylation modification, and belongs to the technical field of magnetic material synthesis. The method comprises the following steps: firstly, preparing MCeO2; the preparation method comprises the following steps: mixing MCeO2, hexadecyl trimethyl ammonium bromide and ammonia water to obtain a mixed solution, adding 1, 2-bis (triethoxysilane) ethane into the mixed solution for reaction to obtain a product, and dispersing the product into an NH4NO3 solution for reflux reaction to obtain Janus MCP; the preparation method comprises the following steps: reacting Janus MCP with a silane coupling agent, dissolving aminated Janus MCP and 4-ethylene sulfonyl benzoic acid in a buffer solution containing EDC and NHS, and reacting to obtain the Janus material. The preparation method is reliable, the material performance is stable, and the enrichment efficiency of the magnetic Janus on target peptide fragments (phosphorylated peptide fragments and palmitoylated peptide fragments) is remarkably improved.

The invention discloses porous starch and a preparation method and application thereof, and the preparation method comprises the following steps: (1) starch pretreatment: taking corn starch as a raw material, fully mixing the corn starch with a calcium chloride solution, performing magnetic stirring for shelling and gelatinization treatment, after the shelling and gelatinization are stopped, centrifuging to take precipitate, washing and drying to obtain shelled starch; (2) enzymolysis treatment: preheating the shelled starch and a citric acid-disodium hydrogen phosphate buffer solution in a constant-temperature water bath to obtain a starch suspension; and adding a compound enzyme into the starch suspension for enzymolysis, centrifuging after enzymolysis is stopped, taking precipitate, drying, and crushing to obtain the porous starch. Compared with the prior art, the specific solution volume and oil absorption rate of the porous starch obtained by the method are obviously increased, and the dissolution rate of the porous starch in water is also obviously increased.

The invention discloses a production process of a modified p-phenylenediamine rubber anti-aging agent, which comprises the following steps: S1, catalyzing a ring-closure reaction through lipase, and accurately controlling pH by combining a phosphate buffer solution, so that the bonding efficiency of 6PPD and tea polyphenol is remarkably improved, and the release amount of aniline is effectively reduced; s2, carrying out spray drying to obtain EP-TP powder to control the particle morphology; s3, increasing the load rate of the anti-aging agent and effectively inhibiting the migration rate of the anti-aging agent through the pore diameter physical confinement of mesoporous silica and an amination gas phase modification technology, and ensuring uniform dispersion of anti-aging agent particles through the synergistic effect of staged load reaction and a polyethylene glycol dispersant; and S4, the particle morphology is cooperatively controlled through vacuum microwave drying, the dispersion requirement of the rubber mixing technology is met, and the interface bonding strength is improved by combining the staged loading reaction with a polyethylene glycol dispersing agent.

The invention discloses a preparation method of a sandwich structure immunosensor based on surface enhanced Raman scattering and application of the sandwich structure immunosensor to detection of an anti-phospholipase A2 receptor antibody, and is characterized by comprising the following steps: sputtering silver ions on a cotton swab / ZIF-67 prepared by an in-situ growth method by adopting an ion sputtering method to obtain a cotton swab / ZIF-67 / Ag NPs composite material; the preparation method comprises the following steps: preparing an antigen solution, then adding the antigen solution into the antigen solution to obtain an immune substrate, adding a methylene blue aqueous solution into a silver nanoparticle solution for reaction, then connecting an anti-human PLA2R IgG antibody to obtain an immune probe, and finally dropwise adding a phosphate buffer solution containing an antibody to be detected onto the immune substrate, and dropwise adding the immune probe solution to the immune substrate adsorbed with the antibody to be detected to obtain the sandwich structure immunosensor based on surface enhanced Raman scattering. The method has the advantages of high sensitivity, good selectivity and strong stability.

The invention belongs to the field of synthesis of nano materials, and particularly relates to a core-shell structure gold nano star and a preparation method and application thereof, and the core-shell structure gold nano star comprises a first gold nano star containing a metal sulfide shell layer and a second gold nano star containing a metal oxide shell layer. The preparation method comprises the following steps: firstly preparing a gold nano star core solution, and then respectively adding different precursors to prepare two core-shell structure gold nano stars. The method has the advantages of simple synthesis conditions and non-toxic reagents. The core-shell structure gold nanostars are used for preparing a detection solution based on a buffer solution, a color developing agent and an oxidizing agent, the detection solution reacts with antioxidants, a data matrix is constructed by measuring absorbance changes and is analyzed, single, binary and ternary combinations of various antioxidants such as ascorbic acid and glutathione can be accurately distinguished, and the detection accuracy is improved. The application prospect in the fields of biomolecules and food detection is good.

The invention discloses a preparation method and application of phytic acid modified zero-valent iron. The method comprises the following steps: (1) mixing phytate and liquid phytic acid according to a molar ratio of (5: 5)-(8: 2), and preparing a buffer solution with the concentration of 0.05-0.5 mol / L; (2) adding micron or nano zero-valent iron into a buffer solution according to a solid-to-liquid ratio of 1: 10 to 1: 50 (g / mL), and transferring to a polytetrafluoroethylene reaction kettle; (3) under the protection of nitrogen, reacting for 6-48 hours under the conditions that the temperature is 20-80 DEG C and the oscillation rate is 100-1000 rpm, and controlling the pH value to be 3.5-5.5; and (4) after the reaction, carrying out suction filtration, ethanol-water alternate washing and vacuum drying to prepare the modified zero-valent iron with the surface coated with the phytic acid iron complex. A stable chelation layer is formed on the surface of phytic acid molecules and zero-valent iron, the oxidation resistance, dispersity and heavy metal adsorption capacity of the material are remarkably improved, and the material is suitable for efficient repair of industrial wastewater.

The invention relates to the field of environmental protection, and discloses a composite sand solidification agent and a preparation method thereof. The cellulose-chitosan composite material comprises the following components: 40-50 parts of cellulose, 80-100 parts of chitosan, 2-4 parts of a cross-linking agent, 1-2 parts of an initiator, 2-4 parts of a dispersant, 20-30 parts of fly ash, 20-30 parts of silicate clinker, 200-240 parts of a sodium hydroxide solution, 10-15 parts of sodium carbonate, 80-100 parts of an ethanol solution of chloroacetic acid, 250-300 parts of a sodium acetate buffer solution, 80-100 parts of ethanol, 240-320 parts of ethylene glycol and 30-40 parts of water. The cellulose is modified and then copolymerized with the chitosan, then the copolymer is loaded with the fly ash and the silicate clinker hydrate, the prepared composite sand solidification agent has high strength and excellent water absorption and retention capacity and is environmentally friendly, and the raw materials cellulose and chitosan are derived from biological raw materials, are wide in source, are easy to degrade and are free of toxicity and pollution; the fly ash is subjected to roasting pretreatment, and degradation of the sand stabilization material in the later period has no obvious negative effect on the ecological environment.

The invention relates to the technical field of plant polysaccharide extraction, in particular to a process for synergistically extracting rape pollen polysaccharide by a compound enzyme, which comprises the following steps: crushing rape pollen to 200-300 meshes by pulse airflow, performing microwave-ultrasonic degreasing by using a 85% ethanol solution, mixing with an acetic acid-sodium acetate buffer solution with the pH value of 4.8, and performing ultrasonic extraction to obtain a crude extract; the method comprises the following steps: adding a compound enzyme system which is immobilized by Fe3O4 (at) SiO2 nanoparticles by cellulase, pectinase, protease and beta-glucosidase according to a mass ratio of 2: 1: 1: 0.5, carrying out enzymolysis for 4 hours in a 50 DEG C constant-temperature water bath and a 15V / cm pulsed electric field, carrying out enzyme deactivation on enzymatic hydrolysate, carrying out gradient ethanol precipitation, carrying out ultrafiltration deproteinization, and carrying out vacuum pulsation freeze drying to obtain the polysaccharide. According to the method disclosed by the invention, the cell wall breakage rate and the enzymolysis efficiency are improved through pulsed airflow crushing, magnetic nano immobilized enzyme and pulsed electric field assistance, the polysaccharide yield reaches 7.32%, the purity is 91%, the beta-glucosidic bond proportion and the antioxidant activity are remarkably improved, the enzyme can be recycled and reused, the drying time is shortened, and efficient and low-consumption extraction is realized.

The invention belongs to the technical field of lignin depolymerization, and particularly relates to a selective fracture method of micromolecular mercaptan mediated lignin beta-O-4 connection. In an H-type electrolytic tank, an anode electrolytic tank takes a buffer solution as an electrolyte, a cathode electrolytic tank takes a lignin beta-O-4 model compound as a reaction substrate, and an acetonitrile / buffer solution mixed solution of small molecular mercaptan is taken as an electrolyte for electrochemical cracking reaction. Wherein a micromolecular mercaptan medium is used as a single electron transfer medium, and can efficiently and selectively break key C beta-O bonds in a lignin beta-O-4 model compound at normal temperature and normal pressure under the catalytic action of current to obtain corresponding phenol and ketone monomers, so that the problems that high temperature, high pressure and expensive catalysts are usually needed in depolymerization in a lignin reduction way are solved.

The invention discloses an anti-phosphoric-acid platinum-based catalyst as well as a preparation method and application thereof, and belongs to the technical field of fuel cells. The preparation method of the anti-phosphoric acid platinum-based catalyst comprises the following steps: mixing a carbon-supported platinum catalyst and molybdate in ethylene glycol, and carrying out condensation reflux to obtain a molybdenum oxide modified carbon-supported platinum catalyst; mixing the molybdenum oxide modified carbon-supported platinum catalyst and dopamine hydrochloride in a buffer solution, stirring for the first time, adding transition metal salt, stirring for the second time, performing suction filtration, and drying to obtain a pretreated molybdenum oxide modified platinum-based alloy catalyst; and carrying out annealing treatment on the pretreated molybdenum oxide modified platinum-based alloy catalyst to obtain the anti-phosphoric acid platinum-based catalyst. The anti-phosphoric acid platinum-based catalyst has excellent oxygen reduction initial activity, anti-phosphoric acid performance and electrochemical stability, and can effectively solve the problem of phosphoric acid poisoning of a platinum-based catalyst of a high-temperature proton exchange membrane fuel cell.

The invention provides a rapid visual D-limonene detection method and application thereof, and belongs to the technical field of analytical chemistry, the method comprises the following steps: uniformly mixing ethanol and water to form a solvent system, sequentially adding template agents Pluronic P123 and Pluronic F127, phloroglucinol, 1, 3, 5-trimethylbenzene and ethylenediamine, and uniformly stirring at room temperature; after the reaction is completed, washing, centrifuging, drying and calcining an obtained sample to obtain DNCzyme; the method comprises the following steps: adding TMB, H2O2 and DNCzyme into an acetic acid-sodium acetate buffer solution HAc-NaAc, finally adding D-limonene, incubating, and carrying out visual detection on the solution. The method for detecting the D-limonene through colorimetric sensing is rapid, simple, convenient, low in cost, high in sensitivity and good in selectivity, and visual detection is achieved by combining a smart phone.

The invention relates to the technical field of pharmaceutical preparations, in particular to a multiple nano emulsion adjuvant and a preparation method thereof. The multiple nano emulsion adjuvant is prepared from 2.73 to 6.37 g of an oil phase matrix based on 100 g of a raw material system, 0.10 to 0.25 g of a sterol compound; 0.212 to 0.424 g of a nonionic surfactant; 0.00050 to 0.00200 g of a triterpenoid saponin type active adjuvant; 0.010 to 0.020 g of an anionic polymer modifier; 0.005 to 0.015 g of a cationic polymer modifier; 70-90 g of a buffer solution; the total mass of the raw materials is 100 g. The nano emulsion adjuvant prepared by the invention can be stored for 6 months at 2-8 DEG C under a low sterol condition, the particle size change does not exceed + 5%, no crystallization or layering is generated, and the stability of the active adjuvant is remarkably improved.

The invention relates to the technical field of medical materials, in particular to an injection composition for endoscopic submucosal dissection and a preparation method and application thereof. The injection composition is prepared from the following raw materials: 1 to 5 w / v percent of sodium hydroxymethyl starch, 0.1 to 10 w / v percent of acetylcysteine, 0.2 to 4 w / v percent of polyvinylpyrrolidone, 0.001 to 0.1 w / v percent of coloring agent and the balance of phosphate buffer solution. The injection composition disclosed by the invention can be directly injected under mucous membranes, plays a role in upheaving diseased regions, has the advantages of long maintenance time and high upheaving degree, and has the effects of stopping bleeding and promoting wound healing.

The invention provides a method for simultaneously detecting perfluorinated compounds in mouse tissues and organs, and belongs to the technical field of analysis and detection. The method provided by the invention comprises the following steps: mixing a mouse visceral organ tissue sample, an alkaline buffer solution and an internal standard solution, and homogenizing to obtain homogenate; mixing the homogenate with tetrabutylammonium hydrogen sulfate and methyl tert-butyl ether, and carrying out liquid-liquid extraction to obtain extract liquor; and sequentially drying and redissolving the extract liquor, and carrying out ultra-high performance liquid chromatography-tandem mass spectrometry analysis to obtain a result of the perfluorinated compound in the mouse tissue visceral organs. The result of the embodiment shows that the adding standard recovery rate of 14 target objects in the method provided by the invention is 64.9%-120.3%, the RSD of 6 repeated tests is 1.0%-14.0%, the matrix effect of the target objects is 83.7%-134.0%, and the matrix effect is relatively low; and the detection result has excellent accuracy and reproducibility.

The invention provides a preparation method and application of red nano-selenium particles, and relates to the technical field of nano-medicines.The preparation method comprises the steps that sodium selenite is dissolved in ultrapure water, silicate microspheres containing copper, zinc and aluminum are added, the pH value is 4.8, 1.5 M of ascorbic acid solution is dropwise added while stirring, the temperature is increased till solid ascorbic acid is added, the pH value is adjusted through NaOH, and nano-selenium suspension liquid is obtained through stirring reaction; the preparation method comprises the following steps: mixing and stirring a nano-selenium suspension, a sodium alginate sulfydryl graphene oxide mixture and a chitosan oligosaccharide citric acid buffer solution, centrifugally washing, and freeze-drying to obtain red nano-selenium particles, and preparing the copper-zinc-containing aluminosilicate microspheres through mesoporous template calcination and copper-zinc co-doping. The red nano-selenium particles prepared by the method have a core-shell structure, uniform particle size, high oxidation resistance and remarkable interface bonding strength.

The invention relates to the technical field of sewage treatment, in particular to an electrostatic spinning PVDF nanofiber membrane for sewage treatment and a preparation method and application of the electrostatic spinning PVDF nanofiber membrane. The preparation method comprises the following steps: dissolving PVDF (Polyvinylidene Fluoride) particles in a mixed solvent of DMF (Dimethyl Formamide) and acetone, adding nano TiO2 particles subjected to APTES (Aminopropyltriethoxysilane) surface modification, and adding PVP (Polyvinyl Pyrrolidone) into the solution to obtain a uniform spinning solution; spinning by adopting electrostatic spinning equipment to obtain a PVDF / TiO2 / PVP nanofiber membrane; the nanofiber membrane is soaked in a sodium hydroxide solution, then the membrane is soaked in a Tris-HCl buffer solution containing dopamine, and the final electrostatic spinning PVDF nanofiber membrane is obtained. The average diameter of nanofibers of the nanofiber membrane is 200-300nm, the porosity of the membrane is 70-80%, and the water contact angle is less than 60 degrees; when the nanofiber membrane is used for treating sewage containing organic pollutants and heavy metal ions, the removal rate of the nanofiber membrane on methyl orange can reach 95% or above; the rejection rate of copper ions can reach 90% or above; the removal efficiency of organic pollutants and heavy metal ions is obviously improved.