214 results about "Gradient centrifugation" patented technology

The invention relates to the technical field of analysis of physical and chemical properties of soil, in particular to a dry farming soil fertility rapid detection and fertility improvement method, which comprises the following steps: sorting a colloidal phase and a dissolved phase of a humic acid complex based on density difference and dielectric property difference through a gradient centrifugation and dielectrophoresis enriched physical field synergistic separation technology; a two-channel detection time sequence is optimized by adopting a genetic algorithm, a non-overlapping time sequence signal flow is generated by taking a signal interference suppression ratio as a fitness function, and time domain cross interference is suppressed. A programmable resistance-capacitance compensation model is constructed, parallel capacitor array parameters are dynamically adjusted to correct electrochemical phase angle offset, and a three-dimensional fertility distribution curved surface and a residual map are generated in combination with a Kriging interpolation model. On the basis of residual spectrum spatial distribution characteristics, a cross-linked slow-release system is deployed to improve the organic matter binding capacity of a humic acid deficiency area, a mesoporous zeolite-based passivator is applied to regulate and control an ion migration path, a closed-loop feedback mechanism is formed through dynamic phase response monitoring, and accurate detection and directional remediation of soil fertility are achieved.

The invention discloses a method for efficiently separating and purifying plant exosomes and application, and belongs to the technical field of biological nanotechnology. The method comprises the following key steps: (1) performing sterile cleaning on plant raw materials, and then performing peeling or tissue slitting pretreatment; (2) carrying out mechanical crushing treatment by adopting a phosphate buffer solution (PBS), and filtering through a 200-mesh screen to obtain a primary extracting solution; (3) performing gradient centrifugal purification on the extracting solution, collecting supernate, and filtering the supernate through a 0.45 mu m microporous filter membrane; (4) adding 8-12% of polyethylene glycol for low-temperature phase separation and precipitation; (5) purifying by using an electrodialysis technology; and (6) carrying out final concentration by adopting a 100kDa ultrafiltration membrane to obtain the high-purity PELNs preparation. According to the method, the process, equipment and reagents are simple and easy to obtain, the final yield is high, the purity is high, particle size distribution is uniform, and an innovative solution is provided for large-scale industrial production of natural-source nano-drug carriers.

The invention relates to the technical field of green manufacturing, in particular to a manufactured cutting fluid recovery treatment method based on an oil-scrap separation system, which comprises the following steps: step 1, dynamic viscosity regulation and control pretreatment; 2, gradient centrifugal separation, wherein the pretreated mixed liquid is subjected to three-stage centrifugal separation; 3, interface adsorption fine treatment is conducted, specifically, the oil liquid obtained after centrifugal separation flows through a layered variable-porosity adsorption tower, and regeneration of an adsorption material is triggered according to the pressure drop change; and step 4, optimizing closed-loop parameters, and dynamically correcting the control parameter thresholds in the steps 1-3 by collecting and processing the associated data of the process parameters and the final oil metal residual quantity. According to the method, through precise matching and dynamic adjustment of multiple steps, the separation effect can be improved to the maximum extent in the green manufacturing and cutting fluid recycling process, waste emission and resource waste are reduced, and the purposes of energy conservation and emission reduction are achieved.

The present invention discloses a porcine Seneca virus neutralization liquid phase blocking ELISA kit, which comprises an effective amount of porcine Seneca virus antigen, an effective amount of porcine Seneca virus single domain antibody 1, an effective amount of porcine Seneca virus single domain antibody 2, and a matching detection reagent. The porcine Seneca virus antigen is porcine Seneca virus particles purified by sucrose density gradient centrifugation, and the particle size of the purified porcine Seneca virus particles is 20 to 30 nm. The amino acid sequence of the heavy chain variable region of the porcine Seneca virus single domain antibody 1 is shown in SEQ ID NO.1. The amino acid sequence of the heavy chain variable region of the porcine Seneca virus single domain antibody 2 is shown in SEQ ID NO.2. The kit of the present invention has the advantages of high efficiency, simplicity, sensitivity, stability, etc., has a good correlation with the traditional diagnostic method virus neutralization experiment, and is suitable for a wide range of applications.

The present invention discloses a method for extracting a stable body from cyanobacteria, comprising the following steps: S1. Cultivating cyanobacteria; S2. Pretreating cyanobacteria; S3. Ultrasonic disruption; S4. Differential centrifugation; S5. Ultrafiltration; S6. Ultracentrifugation; S7. Density gradient centrifugation; S8. Removing peripheral proteins. The extraction method provided by the present invention has high extraction efficiency, stable and controllable process, no toxic by-products, is green and environmentally friendly, and does not require high temperature and high pressure equipment and large instruments and equipment, thereby expanding application scenarios and reducing application costs. The present invention can obtain high polyP n Stable, active granular biomaterials with high polymerization degree, concentration, and purity, as well as high bioactivity, can meet the stringent requirements of applications in the food and daily chemical sectors, as well as clinical medicine and scientific research. They possess significant practical application value and commercial prospects, and will address the technical challenges of preparing stable, active granular biomaterials in China.

The invention provides an exosome enrichment method based on a modified cellulose material, which comprises the following steps: carrying out TEMPO oxidation on plant residue cellulose to prepare a cellulose material with a carboxyl structure; the cellulose structure is further refined by adopting mechanical shearing and high-pressure homogenizing means, so that the specific surface area and the dispersion stability are remarkably improved; through polyethyleneimine PEI grafting, a large number of amino functional groups are introduced, the surface electropositivity of the material is enhanced, and efficient adsorption and enrichment of exosomes with negative charges are achieved. The invention also provides the exosome prepared by the method. The modified cellulose material disclosed by the invention is wide in source, simple and convenient to prepare and mild in enrichment process, the separation purity and the enrichment efficiency of the exosome can be remarkably improved, and the modified cellulose material has good biocompatibility and environmental friendliness; compared with existing ultracentrifugation, density gradient centrifugation and immunoaffinity separation methods, the method has the advantages that the operation process is simplified, the equipment dependence and reagent cost are reduced, and the potential of large-scale production and clinical application is achieved.

The invention discloses a preparation method of polygonatum-sibiricum-sourced exosome-like nano-vesicles and application of the nano-vesicles in antitumor drugs, and relates to the technical field of biological medicines. The preparation method comprises the following steps: crushing fresh rhizoma polygonati slices, filtering and collecting to obtain a first filtrate; carrying out gradient centrifugation treatment on the first filtrate to obtain supernate; carrying out first membrane filtration treatment on the supernate to obtain second filtrate with the particle size of less than 450 nm; centrifuging the second filtrate to obtain a precipitate, and resuspending the precipitate with a PBS buffer solution to obtain a rhizoma polygonati exosome crude extract; and performing secondary membrane filtration treatment on the rhizoma polygonati exosome crude extract to obtain a third filtrate with the particle size of less than 220nm, thereby obtaining the rhizoma polygonati-derived exosome-like nano-vesicles. The polygonatum-sibiricum-sourced exosome-like nano-vesicle has remarkable inhibitory activity on tumors, provides a new strategy and means for tumor treatment, and has important scientific value and clinical application potential.

The invention relates to the technical field of biological medicines, in particular to an umbilical cord source mesenchymal stem cell exosome preparation, a preparation method and application in preparation of osteoarthritis medicines. The preparation is prepared by the method. The method comprises the following steps: pretreating umbilical cord-derived mesenchymal stem cells by adopting a pretreating agent; removing the pretreatment agent, and carrying out gradient centrifugation treatment on the pretreated umbilical cord source mesenchymal stem cells to obtain exosome precipitate; and re-suspending the exosome precipitate in a buffer solution containing a protease inhibitor to obtain the umbilical cord source mesenchymal stem cell exosome preparation. The application refers to the application of the preparation in preparation of osteoarthritis drugs. The problems of low yield and functional heterogeneity of EXO obtained by a conventional culture method are solved.

The invention discloses an extraction method and application of purslane exosomes, belongs to the technical field of plant exosome extraction, and can improve the structural integrity, yield and purity of the purslane exosomes. Comprising the following steps: (1) cutting a weighed purslane sample into pieces, adding 90-120ml of a PBS buffer solution, and soaking overnight to obtain a soaking solution; (2) adding a proper amount of PBS (Phosphate Buffer Solution) into the soak solution, and then carrying out high-speed homogenization treatment for 8-10 times to obtain homogenate; (3) filtering large fragments in the homogenate to obtain a first supernatant; (4) sequentially carrying out gradient centrifugal treatment: centrifuging 1000g for 10 minutes to remove coarse particles, centrifuging 2000g for 20 minutes to remove cell debris, centrifuging 4000 g for 30 minutes to remove large-particle vesicles, and centrifuging 10000g for 60 minutes to remove impurities; (5) filtering the supernate obtained in the step (4) by using a sterile 0.22 mu m filter, and carrying out 120000g ultracentrifugation for 70min to obtain a precipitate; and (6) resuspending the precipitate by using a sterile PBS buffer solution to obtain a purslane exosome suspension.

The invention discloses a natural product-induced artificial nano-vesicle derived from human umbilical cord mesenchymal stem cells and application of the natural product-induced artificial nano-vesicle in ischemic diseases. The preparation method of the nano vesicle derived from the human umbilical cord mesenchymal stem cells comprises the following steps: S1, inoculating the human umbilical cord mesenchymal stem cells to a 3D microcarrier; then adding traditional Chinese medicine active ingredients to activate the human umbilical cord mesenchymal stem cells, continuing to culture, cracking the microcarrier, and harvesting cells; s2, dispersing the human umbilical cord mesenchymal stem cells obtained in S1 to obtain a suspension, extruding the suspension through a polycarbonate film, and then discarding large particles by adopting a gradient centrifugation method to obtain the nano-vesicles. Compared with naturally secreted exosomes, the exosome has the advantages that the yield is increased, the treatment efficiency is improved, the production cost is reduced, and compared with stem cells, the problems of low transplantation rate and the like are avoided. The stem cells are pretreated based on the traditional Chinese medicine, the vesicles are extracted by utilizing an extrusion method, and the yield and the treatment efficiency of the nano vesicles are remarkably improved.

The invention relates to an extraction method, a modification method and application of dendrobium nobile outer vesicles. The method comprises the following steps: placing dendrobium nobile leaves in a phosphate buffer solution, crushing and separating to ensure that plant cells are fully broken and outer vesicles are released; then a differential centrifugation method is combined with sucrose gradient centrifugation, finally, the outer vesicles in a sucrose solution with the mass concentration of 30-45% are selected, and the extracted dendrobium nobile outer vesicles are moderate in mass and high in purity. Then cholesterol structural analogues such as sterol compounds and triterpenoid saponin active molecules are embedded into a phospholipid bilayer of the dendrobium nobile outer vesicles to modify the dendrobium nobile outer vesicles, and the modification strategy can effectively improve the stability of the dendrobium nobile outer vesicles in a complex physiological environment; and the treatment effect can be enhanced through the synergism of active molecules and endogenous components of the vesicles.

The invention relates to the technical field of biological medicines and ophthalmic medicines, in particular to a herbal exosome composition for eye care and treatment and a preparation method thereof. The composition comprises a synergistic combination of herbal exosomes and mesenchymal stem cell exosomes, and further comprises a nano slow-release carrier system. Wherein the herbal exosome is extracted from a traditional herbal plant liquorice by combining gradient centrifugation with a molecular exclusion chromatography method, and herbal active ingredients, namely astragaloside and quercetin, are loaded in the exosome by adopting an electroporation method, so that the pharmacological activity of the exosome is enhanced. The nano slow-release carrier system is of a two-phase slow-release structure; an inner phase is a phospholipid complex loaded with herbal exosomes and mesenchymal stem cell exosomes, and an outer phase is temperature-sensitive hydrogel; the compound is in a liquid state at room temperature, and is rapidly converted into a gel state after being dropped into the ocular surface, so that the retention time of the medicine on the ocular surface is remarkably prolonged, the bioavailability is improved, and the targeting slow release capability aiming at ocular surface tissues is endowed to the compound.

The invention relates to the technical field of carbon nanotubes, and particularly discloses a purification method of a carbon nanotube. The purification method of the carbon nano tube comprises the following steps: (1) weighing a carbon nano tube crude product and various raw materials, (2) adding the carbon nano tube crude product and a surfactant into deionized water, and carrying out ultrasonic dispersion to obtain a dispersion liquid, (3) carrying out gradient centrifugation on the dispersion liquid, and taking an upper-layer suspension liquid, and (4) mixing hydrochloric acid, nitric acid and the suspension liquid, and treating the carbon nano tube to obtain the carbon nano tube. (5) treating the carbon nano tube by dilute acid, mildly oxidizing the carbon nano tube by using a low-concentration hydrogen peroxide solution, and then placing the carbon nano tube in a magnetic field to adsorb magnetic impurities, (6) carrying out cross-flow filtration by using a polycarbonate microfiltration membrane and collecting the treated carbon nano tube, and (7) annealing the treated carbon nano tube by using inert gas and freeze-drying to obtain the purified carbon nano tube. According to the purification method, the metal catalyst, amorphous carbon and graphite impurities can be efficiently removed, and meanwhile, the integrity of the tube wall of the carbon nano tube is kept.

The invention discloses a preparation method and application of a gynostemma pentaphylla exosome. According to the method, a high-activity callus is obtained by optimizing a callus induction culture medium, and a suspension culture system is established to realize biomass accumulation with the dry cell weight of 19.8 + / -0.7 g / L. A sequential progressive composite induction strategy (methyl jasmonate is added after chitosan is pre-induced for 24 hours) is innovatively adopted, so that the saponin content is remarkably increased to 102.6 + / -4.8 mg / g DW. Exosomes (P-Exos) are extracted from induced cells through an enzymolysis-magnetic bead affinity purification technology (WGA modified magnetic bead affinity capture after mild enzymolysis of a cracking buffer solution), the yield reaches 1.45 + / -0.08 mg / g cells, and the extraction efficiency is remarkably improved compared with that of a traditional gradient centrifugation method (C-Exos). Moreover, the gynostemma pentaphyllum exosome prepared by the invention can effectively improve the synthesis of skin collagen, has a better effect, can be applied to medicines for promoting skin wound repair or can be added into anti-aging cosmetics as a functional component, and has a very high application value.

The invention belongs to the field of biotechnology and aquaculture, and particularly relates to a method for improving hypoxia resistance of pelteobagrus vachelli based on hypoxia induction of liver extracellular vesicles of the pelteobagrus vachelli. The method comprises the following steps: extracting high-purity extracellular vesicles EVs in liver tissues of pelteobagrus vachelli subjected to low-oxygen treatment by adopting a method of combining differential centrifugation and high-precision iodixanol density gradient centrifugation; diluting the extracted EVs to 2mu g / mu L by using PBS (Phosphate Buffer Solution) to prepare an EVs suspension; an intraperitoneal injection mode is adopted, the EVs suspension is injected into the body of the pelteobagrus vachelli, and after injection is conducted for 24 hours, the hypoxia resistance of the pelteobagrus vachelli is evaluated through a suffocation point detection test. The invention opens up a brand new path for improving the hypoxia resistance of the pelteobagrus vachelli, provides a new idea and a new method for efficiently enhancing the hypoxia resistance of economic fishes in the field of aquaculture, is expected to play an important role in actual aquaculture production, and assists the sustainable development of the aquaculture industry.

The invention relates to the technical field of bioengineering, in particular to an SOD (superoxide dismutase) impurity removal and purification process which comprises the following steps: extracting SOD enzyme from fresh animal blood, separating high-purity red blood cells through gradient centrifugation, preparing a crude extract by combining hypotonic lysis and freeze thawing strengthening, then selectively precipitating hemoglobin and other heat-sensitive impurity proteins by adopting a gradient temperature rise thermal denaturation method, and purifying to obtain the SOD impurity removal and purification process. The method comprises the following steps: extracting SOD, removing pigments and lipid impurities by using a mixed adsorbent, further enriching SOD by using ammonium sulfate salting-out, and finally obtaining high-purity SOD powder through vacuum freeze drying by combining ion exchange chromatography and ultrafiltration concentration technologies. The method has the advantages of high efficiency, rapidness and low cost, impurities can be effectively removed through a combined process of hypotonic / freeze-thaw cracking, hemoglobin removal through thermal denaturation, ammonium sulfate salting-out, ion exchange chromatography and ultrafiltration concentration, the purity and the recovery rate of the SOD enzyme are remarkably improved, the whole purification process is carried out at 4 DEG C, and the method is suitable for industrial production. The influence of high temperature on the activity of the SOD enzyme is avoided.

The invention discloses a rapid and efficient extraction method of extracellular vesicles rich in mitochondria. The extraction method comprises the following steps: (1) culturing mitochondrial donor cells in vitro; (2) treating the mitochondrial donor cells with cytochalasin D; (3) collecting the cells; (4) oscillating a cell suspension; according to the method disclosed by the invention, by combining cytochalasin D treatment with a subsequent gradient centrifugal separation step, a sample of extracellular vesicles rich in mitochondria can be efficiently extracted, meanwhile, the defects existing in a traditional mitochondrial transplantation technology are overcome, and a new thought and method are provided for clinical application of mitochondrial transplantation.

The invention relates to a method for extracting high-purity extracellular vesicles from liver tissues of pelteobagrus vachelli, which comprises the following steps of: firstly, mixing collagenase II and collagenase IV, performing enzymolysis on the tissues, adding a CaCl2 solution, incubating, and digesting the liver tissues into a tissue suspension; then removing cells and fragments through low-speed centrifugation, and filtering to remove impurities by using needle filters of 0.8 [mu] m and 0.22 [mu] m; and finally, further purifying by combining ultracentrifugation with a high-precision iodixanol density gradient centrifugation method, and merging density layers with high purity to obtain high-purity EVs. The method has the characteristics of high extraction purity, high efficiency and simplicity and convenience in operation, and has a wide application prospect.

The invention discloses a zebra fish spermatogonial stem cell separation and transplantation method, and belongs to the technical field of fish germline stem cell separation. The method comprises the following steps: washing complete sexual glands of zebra fish testis by adopting penicillin / streptomycin double-antibody-containing PBS (Phosphate Buffer Solution), physically shearing, digesting and dissociating, and filtering by a screen, so as to obtain zebra fish testis cell suspension; performing density gradient centrifugation to obtain zebra fish spermatogonial stem cells; dyeing, marking, centrifuging, washing, re-suspending, and carrying out micro-injection transplantation to enter the back of the abdominal cavity of the acceptor zebrafish juvenile fish. According to different physical properties of different cells, spermatogonial stem cells are separated, purified and transplanted from zebra fish testis cell suspension by adopting a density gradient centrifugation method, and migration and proliferation processes of donor germ cells can be observed in receptor fish after fluorescence labeling. And a new technical path is provided for fish germplasm resource preservation, endangered fish protection, economic cultured fish yield increase and new variety cultivation.

The invention relates to the technical field of food component analysis and testing, in particular to a fruit pectin sampling and testing method which comprises the following steps: step 1, directionally freezing and crushing, and calculating a target freezing temperature according to a tissue freezing point temperature and cell structure characteristics of a to-be-tested fruit; step 2, gradient centrifugal separation: mixing the crushed particles with a low-temperature protection buffer solution, and maintaining the temperature to be lower than the critical gelation temperature; executing three-stage centrifugation; parameters of each stage are corrected in real time according to physical characteristics of a preorder isolate; 3, dynamic turbidity detection: mixing a pure pectin component with a reaction solution containing a chelating agent and positive ions; calculating the pectin content according to the geometrical characteristic parameters of the characteristic inflection points, and calibrating a calculation model through a standard atlas database. The method can effectively solve the problems of tissue damage and impurity interference in berry fruits and seed-containing fruits, ensures the accuracy and reliability of pectin detection, and has important technical advantages and application prospects.

The invention is applicable to the technical field of biology, and provides a method for rapidly extracting plant rhizome extracellular vesicles from monosaccharide and compound enzyme. According to the method, the plant extracellular vesicles are extracted by an enzymolysis-monosaccharide solution extraction coupling method for the first time, and the defect that an extraction method is single is overcome. According to the method, the conditions are mild, the primary property, the integrity and the biological activity of the vesicle structure are kept, the extraction purity is high, and the particle size distribution is uniform and concentrated in the range of 20-300 nm. The total protein extraction amounts of glucose, galactose and fructose solutions are respectively increased by 36.09% + / -1.18%, 37.65% + / -2.83% and 36.83% + / -2.59% compared with those of PBS (Phosphate Buffer Solution) extraction treatment. In addition, the'single ultracentrifugation 'purification process overcomes the problem of time consumption of traditional gradient centrifugation, and the time is shortened by more than 3h compared with that of a traditional extraction method. The method breaks through the technical bottleneck of large-scale production of the plant extracellular vesicles, and has great application and popularization values.

The invention provides a purification method of mesenchymal stem cell exosomes, prepared mesenchymal stem cell exosome particles and application of the mesenchymal stem cell exosome particles, and belongs to the technical field of exosomes. The preparation method comprises the following steps: performing multiplication culture on adipose-derived stem cells to stimulate exosome secretion, then performing gradient centrifugation, collecting supernate, adding a protective agent, uniformly stirring and mixing, adding a polymer, stirring and incubating, centrifuging, collecting exosome particles, washing, and freeze-drying to obtain the mesenchymal stem cell exosome particles. The mesenchymal stem cell exosome particle prepared by the invention is simple in preparation method, relatively low in cost, easy to realize industrial application and high in yield, meanwhile, the mesenchymal stem cell exosome particle has a very good protection effect on exosomes, the preservation period of the exosomes is prolonged, and the prepared mesenchymal stem cell exosome particle has the characteristic of releasing the exosomes in a sustained and controlled release manner and has a good application prospect. The traditional Chinese medicine composition is widely applied to preparation of anti-inflammatory, anti-oxidation and skin repair promoting medicines.

The invention belongs to the technical field of biotechnology and tissue engineering, and particularly relates to application of pilose antler bud cell secretions in preparation of anti-osteoporosis drugs. The pilose antler bud cell secreta is obtained by adopting gradient centrifugation, and cell experiments show that the pilose antler bud cell secreta provided by the invention has the effect of promoting osteogenic differentiation of cells; animal experiment results show that the cornu cervi pantotrichum bud cell secreta provided by the invention can significantly improve the bone mineral density, bone volume fraction, bone trabecula number, bone trabecula thickness, bone trabecula separation degree and cortical bone mineral density of mice, increase the bone trabecula area of primary osteogenesis and secondary osteogenesis centers of the mice, improve osteoporosis symptoms of the mice, and improve osteoporosis of the mice. The effect is obviously better than that of bone marrow mesenchymal stem cell secretions, part of indexes are equivalent to the treatment effect of diphosphates, and the antler bud cell secretions provided by the invention can be used for preparing medicines for preventing, relieving or treating osteoporosis.

The invention is applicable to the technical field of biology, and provides a method for rapidly extracting plant rhizome extracellular vesicles by disaccharide and compound enzyme. According to the method, an enzymolysis-disaccharide solution extraction coupling method is created for the first time to extract the plant extracellular vesicles, and the defect that an extraction method is single is overcome. According to the method, the conditions are mild, the primary property, the integrity and the biological activity of the vesicle structure are kept, the extraction purity is high, and the particle size distribution is uniform and concentrated in the range of 40-300 nm. Compared with PBS (Phosphate Buffer Solution) extraction treatment, the total protein extraction amounts of lactose, cane sugar and maltose solutions are respectively increased by 20.04% + / -4.50%, 35.00% + / -5.74% and 36.45% + / -2.68%. In addition, the'single ultracentrifugation 'purification process overcomes the problem of time consumption of traditional gradient centrifugation, and the time is shortened by more than 3h compared with that of a traditional extraction method. The method breaks through the technical bottleneck of large-scale production of the plant extracellular vesicles, and has great application and popularization values.

The invention discloses construction of a Guangdong small-ear spotted pig spermatogonial stem cell in-vitro culture system and screening of surface markers, and belongs to the technical field of cell culture.The technical scheme includes that testis are broken firstly, then enzyme digestion, density gradient centrifugal purification and differential adherent purification are conducted, and purified spermatogonial stem cells are obtained; inoculating the obtained spermatogonial stem cells to feeder layer cells and culturing in a culture medium; the culture medium is a DMEM culture medium added with FBS and growth factors; the mass fraction of the FBS in the DMEM culture medium is 8-12%, an enzyme digestion method, a density gradient centrifugation method and a differential adhesion method are combined for application, the Guangdong small-ear spotted pig spermatogonia stem cells with certain purity are obtained, cells enriched and purified in vitro can proliferate massively, and an in-vitro culture system of the Guangdong small-ear spotted pig spermatogonia stem cells is established.

The invention relates to the technical field of livestock and poultry breeding, in particular to a goat hybridization breeding method capable of achieving complete-cycle nutrition enhancement. The core of the method is that systematic nutrition intervention runs through the whole breeding process. Before hybridization, performing differential nutrition pretreatment on the parents for 60 days: feeding the female parents with a breeding nutrition enhancer added with components such as D-chiro-inositol and N-acetylcysteine, and supplementing sperm motility enhancer containing acetylated L-carnitine and ergothioneine to the male parents. In the gamete treatment stage, the oocytes are subjected to in-vitro maturation culture in a special culture solution containing components such as D-chiro-inositol and a growth differentiation factor 9; after the sperms are subjected to gradient centrifugal screening, completing in-vitro fertilization in an optimized fertilization culture solution; after the embryos develop into blastocysts in the sequential culture system, carrying out laparoscopic transplantation, and carrying out staged precise nutrition culture on the pregnant ewes. According to the method, through multi-level nutrition enhancement, the reproductive capacity of the goats and the growth performance of offspring are effectively improved.

The invention relates to the technical field of anti-aging preparations, and particularly discloses an anti-aging preparation of a human exosome combined with a plant exosome as well as a preparation method and application of the anti-aging preparation. The invention provides an anti-aging preparation combining a human exosome and a plant exosome. The anti-aging preparation specifically comprises the following components in parts by weight: 8-12 parts of the human exosome, 3-7 parts of the plant exosome and 0.5-1.5 parts of collagen, the preparation method of the plant exosome comprises the following steps: taking beet root tubers and mesembryanthemum crystallinum in a weight ratio of (0.5-3): (7-11) as raw materials, crushing the raw materials, adding a buffer solution, and then sequentially carrying out wall breaking treatment, gradient centrifugation to take supernate, dilution, deep filtration, concentration and purification to obtain the plant exosome. According to the technical scheme provided by the invention, the prepared anti-aging preparation has relatively strong oxidation resistance, saccharification resistance and stability, and has a relatively strong anti-aging effect when being used in skin care products.

The invention discloses a purification method of cord blood mesenchymal stem cell source exosome, and relates to the technical field of bioengineering. The method comprises the following steps: firstly, carrying out pH regulation pretreatment on cell culture supernate through a technical path of combining gradient centrifugation and membrane filtration, and sequentially removing cell debris and large-particle impurities by adopting multi-stage differential centrifugation; then carrying out selective protein precipitation by utilizing polyethylene glycol with specific molecular weight, and realizing fine separation of the exosome by combining sucrose-meglumine diatrizoate density gradient centrifugation; and finally, terminal purification is completed under low-temperature and low-pressure conditions through a polyethersulfone membrane filtration system with an optimized pore size. According to the method, centrifugal parameters, reagent concentration and filtering conditions are precisely regulated and controlled, so that the particle size of the obtained exosome is intensively distributed in the range of 30-150nm, the protein purity reaches 95% or above, the recovery rate exceeds 85%, and the separation efficiency and quality of the exosome are remarkably improved.

The invention relates to the technical field of nano enzymes, and discloses a preparation method of a black phosphorus-gold nano composite material based on ice bath and ultrasonic exfoliation, which comprises the following steps: step 1, preparing BP sheets: dispersing BP powder in deoxygenated water, and carrying out ultrasonic exfoliation under an ice-water bath condition; carrying out gradient centrifugal separation, and collecting precipitates; carrying out freeze drying to obtain BP nanosheets, and dispersing the BP nanosheets to obtain a BP nanosheet dispersion liquid; step 2, preparation of a composite material: adding a surfactant and a chloroauric acid solution, and performing ultrasonic mixing under a protective atmosphere; and then dropwise adding a NaBH4 aqueous solution, and washing to obtain the composite material. Through cooperation of the black phosphorus nanosheet and the gold nanoparticles, the gold nanoparticles are loaded on the surface of the black phosphorus nanosheet, and the stability of the black phosphorus nanosheet is improved by the gold nanoparticles, so that the composite material has a relatively high photothermal conversion rate, and the composite material has a better photothermal effect than single black phosphorus, thereby realizing photothermal therapy.

The invention relates to the technical field of preparation of bone cement, and particularly discloses a preparation method of a photo-thermal response type gold nanorod-bone cement composite material. The method comprises the following steps: synthesizing a gold seed solution; constructing a growth solution; controlling the growth of the nanorod; gradient centrifugal purification; carrying out surface ligand exchange (sulfydryl-PEG); preparing a bone cement composite material; curing and forming; gold nanorods (GNRs) are uniformly embedded into a polymethyl methacrylate (PMMA) bone cement matrix, so that the problems that free nanorods are easy to migrate and poor in bone targeting are solved. The local temperature can be accurately controlled, and damage to surrounding tissues is avoided. According to the invention, immunogen cell death (ICD) can be effectively induced, and anti-tumor immune response can be activated. According to the invention, enough mechanical support can be provided, and the stability after implantation is ensured.