148 results about "Gradient centrifugation" patented technology

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 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 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 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 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 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.

The invention discloses a qualitative and quantitative detection method for graphene in a fiber fabric based on microwave assistance, and relates to the technical field of nano material analysis and detection. The qualitative and quantitative detection method comprises the following steps: adding a solvent and a dispersing agent into a fiber fabric sample, carrying out microwave-assisted dissolution treatment, adding the obtained mixture into a microwave-vortex ultrasonic-centrifugal integrated treatment system, and carrying out vortex dispersion, ultrasonic stripping and gradient centrifugal separation to obtain enriched graphene precipitate; the graphene precipitate is uniformly mixed with an internal standard substance silicon carbide, Raman spectroscopy is adopted for testing, qualitative analysis is carried out by analyzing the characteristics of a G peak and a 2D peak, and quantitative calculation is carried out on graphene according to the intensity ratio of a D peak to a silicon carbide characteristic peak. The method is efficient and accurate, and effectively solves the problems of low treatment efficiency, high cost, environmental pollution, easy damage of graphene structure and insufficient quantitative analysis precision of a traditional method.

The invention relates to the technical field of preparation of nano aluminum oxide functional materials, in particular to a method for preparing nano aluminum oxide based on gradient centrifugation and a supercritical technology. The method comprises the following steps: carrying out dispersion treatment on a hydrophilic solvent, an aluminum oxide raw material and a dispersing agent to obtain initial slurry; under the condition of constant temperature, the initial slurry is subjected to graded grinding, and refined slurry is obtained; the graded grinding sequentially comprises first-stage grinding, second-stage grinding and third-stage grinding; carrying out gradient centrifugation on the refined slurry to obtain concentrated slurry; the gradient centrifugation sequentially comprises first-stage centrifugation, second-stage centrifugation and third-stage centrifugation; carrying out supercritical drying on the concentrated slurry by using carbon dioxide and a silane coupling agent to obtain coarse alumina powder; and drying the coarse alumina powder in vacuum to obtain the nano alumina. According to the method, through multi-unit collaborative integration of graded grinding, gradient centrifugation and supercritical drying, the production target of high-purity, narrow-particle-size-distribution and low-agglomeration-rate nanometer aluminum oxide is achieved, and the use performance of the nanometer aluminum oxide product is remarkably improved.

The invention provides a preparation method and application of high-palatability carrot dietary fibers. The method comprises the following steps: (1) washing and dicing carrots; (2) cellulase and saccharifying enzyme enzymolysis; (3) constructing a two-phase system, adding a compound enzyme and pectinase, and carrying out gradient enzymolysis; (4) carrying out enzyme deactivation and centrifugation to obtain a water phase; (5) performing gradient centrifugation to obtain mixed fibers; (6) precipitating, and collecting precipitated fibers; (7) adding carrot source nano cellulose to obtain a composite fiber with a core-shell structure; and (8) drying, crushing and sieving. According to the preparation method disclosed by the invention, the core problems of rough taste (large particle size), astringent taste (residual acetyl groups and terpene substances), weak function and low purity in the traditional carrot dietary fiber preparation process are solved through a water-alcohol two-phase gradient composite enzymolysis and nano cellulose composite purification process; and finally, the high-palatability carrot dietary fiber which is fine, smooth, free of rough feeling, natural, fresh and sweet, high in purity and strong in function is prepared.

The invention discloses a nucleic acid extraction-free direct RT-qPCR (reverse transcription-quantitative polymerase chain reaction) quantitative analysis method for RNA (Ribonucleic Acid) in tissue, which comprises the following steps: S1, preparing a tissue nucleic acid extraction-free lysis solution, mixing the tissue nucleic acid extraction-free lysis solution with a tissue sample, performing homogeneous crushing treatment, performing gradient centrifugation, and taking supernatant as a reverse transcription template; s2, designing a specific primer probe combination for RNA to be detected, performing reverse transcription on the reverse transcription template obtained in the S1, adding a reverse primer into a reverse transcription system during reverse transcription, and performing reverse transcription to obtain cDNA (complementary deoxyribonucleic acid); and S3, carrying out quantitative analysis on a tissue sample by taking the cDNA obtained in S2 as a template. According to the method provided by the invention, a nucleic acid extraction step is not needed, the detection time is remarkably shortened, the cost is reduced, meanwhile, target RNA is prevented from being lost, the accuracy and the stability of a quantitative result are improved, and the method is suitable for efficient detection of RNA in various tissues.

The invention belongs to the field of biological medicine, and relates to a curcumin-loaded bone marrow mesenchymal stem cell source exosome which is obtained by the following steps: step 1, culturing BMSCs (bone marrow mesenchymal stem cells): simultaneously adding 10% of fetal calf serum and 1% of myclostreptomycin into an MEM culture medium, culturing at 37 DEG C under 5% CO2, and counting and subculturing when the cell density reaches 90%; 2, dissolving Cur in a DMSO solution, preparing a mother solution with the culture medium, and filtering and diluting to 30-50 [mu] g / mL; adding into BMSCs (bone marrow mesenchymal stem cells) with the cell density of 85-100%, and culturing for 12-36 hours; collecting supernate, and carrying out gradient centrifugation to obtain the mesenchymal stem cell source exosome loaded with curcumin. The invention provides a novel administration route which depends on the self function of the mesenchymal stem cell source exosome and the self function of the curcumin at the same time.

The invention relates to the technical field of ovarian cancer cell membrane modification, and discloses an ovarian cancer cell membrane modified co-loaded DOX / IND nanoparticle and a preparation method thereof.The ovarian cancer cell membrane modified co-loaded DOX / IND nanoparticle comprises IND, DOX and ID8 cell membranes, and the preparation method comprises the following steps that 1, DOX / IND (at) cmLPs is prepared, a film dispersion ultrasonic method and an ammonium sulfate gradient method are adopted for constructing a co-loaded DOX / IND liposome, and the liposome is used for preparing the ovarian cancer cell membrane modified co-loaded DOX / IND nanoparticle; the method comprises the following steps: (1) preparing an ovarian cancer cell membrane by adopting a gradient centrifugation method, (2) preparing the ovarian cancer cell membrane by adopting a gradient centrifugation method, (3) preparing ovarian cancer cell membrane fused Indoximod and DOX co-loaded lipidosome (DOX / IND (at) cmLPs), and (4) detecting and verifying the characterization of the DOX / IND (at) cmLPs. According to the ovarian cancer cell membrane modified co-loaded DOX / IND nanoparticle and the preparation method thereof, a liposome co-loaded with DOX / IND is constructed by adopting a thin film dispersion ultrasonic method and an ammonium sulfate gradient method, the technical bottleneck of DOX / IND co-loading is solved through process optimization, and the ovarian cancer cell membrane modified co-loaded DOX / IND nanoparticle has the characteristics of high encapsulation efficiency, synergistic curative effect and intelligent release; a new thought is provided for combined treatment of drug-resistant tumors such as ovarian cancer.

This invention discloses a method for isolating and preparing Chlorella exovesicles. Specifically, Chlorella, conventionally cultured to the early logarithmic growth phase, is induced to develop in a nitrogen-limited medium. The culture medium is then concentrated using a tangential flow filtration system. Finally, the concentrate is subjected to density gradient centrifugation with iodixanol. After centrifugation, components within the density range of 1.10–1.12 g / mL are collected to obtain the Chlorella exovesicle product. This invention achieves concentrated and precise collection of Chlorella exovesicles by regulating membrane lipids during the early induction culture of Chlorella, combined with TFF concentration and density gradient centrifugation. This method effectively eliminates impurities, achieving a recovery rate of over 60% and a purity of 2.56 × 10⁻⁶. 10 The particle / μg method provides an efficient, controllable, and scalable solution for the industrial-scale separation and preparation of microalgal exovesicles.

The present application relates to the technical field of biological medicine, in particular to a kind of umbilical cord-derived mesenchymal stem cell exosome preparation, preparation method and application in preparation of osteoarthritis drugs.The preparation is prepared by the method.The method comprises pretreating umbilical cord-derived mesenchymal stem cells with a pretreatment agent;discard the pretreatment agent, and gradient centrifugation treatment is carried out to the pretreated umbilical cord-derived mesenchymal stem cells, to obtain exosome precipitate;the exosome precipitate is resuspended in a buffer containing protease inhibitor to obtain umbilical cord-derived mesenchymal stem cell exosome preparation.The application is the application of the preparation in the preparation of osteoarthritis drugs.The present application solves the problems of low yield and functional heterogeneity of EXO obtained by conventional culture method.

This invention relates to the field of hydraulic oil purification technology, specifically a method for online hydraulic oil purification and performance regeneration based on centrifugal force field control. The method includes: online acquisition of real-time operating parameters of the hydraulic system and hydraulic oil state data; prediction of contaminant concentration distribution and deteriorated component content; dynamic calculation of the centrifugal force field intensity distribution curve using a state inversion algorithm; and control of the centrifugal device to form a gradient-changing directional centrifugal force field. Based on gradient centrifugation, the method removes solid particles, free water, and colloidal substances step-by-step. Simultaneously, it fine-tunes the local intensity of the centrifugal force field according to the deteriorated component content, selectively removing deteriorated oil molecular components while retaining intact base oil and effective additives. This method enables precise online grading and purification of hydraulic oil, adapts to the real-time state of the oil, improves impurity removal, simultaneously completes oil performance regeneration, and optimizes the quality of purification and regeneration treatment.

The invention relates to a porous sodium hyaluronate microsphere as well as a preparation method and application thereof. The preparation method comprises the following steps: (1) preparing a water phase: dissolving sodium hyaluronate in an alkaline solution containing a chemical foaming agent to obtain an alkaline aqueous solution containing the sodium hyaluronate and the chemical foaming agent, and then mixing the alkaline aqueous solution with a cross-linking agent to obtain the water phase; preparing an oil phase: dissolving an emulsifier in the oil phase matrix to obtain the oil phase; (2) adding the water phase obtained in the step (1) into the oil phase, carrying out a cross-linking reaction, and then carrying out a foaming reaction by adopting a heating method or an acid titration method; and after the reaction is completed, cleaning and removing an oil phase by a gradient centrifugation method to obtain the porous sodium hyaluronate microspheres. According to the method, the occupation effect of a foaming agent in a cross-linking agent is utilized, the foaming agent generates gas through a heating method or an acid titration method, holes are reserved in the cross-linking gel and on the surface of the cross-linking gel in the gas escaping process, and therefore the porous sodium hyaluronate microspheres are prepared.

The application provides a mesenchymal stem cell exosome purification method, a prepared mesenchymal stem cell exosome particle and an application thereof, and belongs to the technical field of exosomes. Fat mesenchymal stem cells are subjected to expansion culture to stimulate exosome secretion, then gradient centrifugation is performed, supernatant is collected, a protective agent is added, stirring and mixing are uniformly performed, a polymer is added, stirring and incubation are performed, centrifugation is performed, exosome particles are collected, washing is performed, freeze-drying is performed, and the mesenchymal stem cell exosome particles are prepared. The prepared mesenchymal stem cell exosome particles have the characteristics of simple preparation method, low cost, easy industrial application, high yield, good protection effect on exosomes, prolonged preservation period, and slow and controlled release of exosomes, and have wide application in the preparation of anti-inflammatory, antioxidant and skin repair promoting drugs.

The application provides a high-aspect-ratio basalt nanosheet and a preparation method thereof, which utilizes basalt flake as raw material, and makes the lamellar structure on the surface of the basalt flake finally fall off to form the basalt nanosheet through cavitation effect generated by a cell crusher. The basalt flake which is not peeled off will have intense cavitation effect between the layers of the basalt flake under the action of mechanical stirring combined with ultrasonic, so that the basalt flake is peeled off again to form a large amount of basalt nanosheets. The mixed liquid obtained by mixing the basalt nanosheets prepared by the above two methods is subjected to gradient centrifugation, different centrifugal forces are used to screen the basalt nanosheets with different sizes, and the basalt nanosheet with high aspect ratio is obtained. The application provides a new idea for large-scale preparation of the basalt nanosheet, reuses the waste basalt flake after initial peeling, and prepares a large amount of basalt nanosheets through a chemical and mechanical method, thereby enriching the preparation system of the basalt nanosheet.

The invention relates to the technical field of medicines, in particular to an extraction method and application of cordate houttuynia exosome-like nanoparticles. The method comprises the steps of pretreatment, impurity removal through differential centrifugation, fine filtration, ultra-speed centrifugation crude extraction, sucrose density gradient centrifugation purification, washing and the like. By optimizing key process parameters, the HELNs with the average particle size of 50-150nm and the typical double-layer membrane cup-shaped vesicle form can be stably obtained. Experiments prove that the HELNs prepared by the method have independent and direct anti-staphylococcus aureus activity. Based on the newly discovered biological activity, the invention provides new application of the HELNs in preparation of products (such as antibacterial drugs, dressings, coatings, lotions and the like) for inhibiting staphylococcus aureus and / or treating infection of staphylococcus aureus. The method is standard in operation and good in repeatability, and widens the application field of active ingredients of houttuynia cordata.

The invention belongs to the technical field of drug delivery and tumor immunotherapy, and particularly relates to an oncolytic virus vesicle as well as a preparation method and application thereof. The preparation method comprises the following steps: co-incubating oncolytic adenovirus and platelets in a buffer system containing prostaglandin E2, and inducing to form an inner membrane encapsulation body; and activating and releasing the vesicles under the conditions of 36-38 DEG C and 4-6% CO2, and carrying out gradient centrifugal collection of 300g, 2000g, 10000g and 100000g. The particle size of the oncolytic virus-loaded vesicle is 50-200nm, the surface of the oncolytic virus-loaded vesicle contains CD41, CD61 and P-selectin, and the oncolytic virus-loaded vesicle can realize long circulation and lung targeting delivery of oncolytic viruses, is suitable for preparing drugs for treating breast cancer and breast cancer lung metastasis, and has a remarkable tumor inhibition effect.

This invention discloses a Polygonatum sibiricum vesicle preparation for treating premature ovarian failure, its preparation method, and its application. The preparation method includes: cleaning Polygonatum sibiricum, juicing, filtering to remove residue, and collecting the juice; subjecting the juice to gradient centrifugation to remove residual plant tissue, plant cells, and plant cell debris; then using an extraction reagent for stepwise precipitation, collecting the precipitate, and resuspending it to obtain the final product. The Polygonatum sibiricum vesicle preparation prepared by this invention can be efficiently taken up by ovarian granulosa cells. It effectively treats premature ovarian failure by activating the Nrf2 signaling pathway, upregulating antioxidant enzyme expression, scavenging reactive oxygen species, restoring mitochondrial membrane potential, inhibiting apoptosis, and restoring the expression levels of estrogen, follicle-stimulating hormone, and anti-Müllerian hormone. The preparation method of this invention is standardized, biocompatible, and safe, and has broad clinical application prospects.

The invention belongs to the technical field of natural exosomes, and particularly relates to a Chinese herbal medicine radix achyranthis bidentatae exosome and an extraction method thereof. According to the method, the exosome is successfully extracted from the radix achyranthis bidentatae for the first time in a differential gradient centrifugation manner, and cellulose and polysaccharide in the radix achyranthis bidentatae extract are subjected to enzymolysis by using cellulase and pectinase, so that the influence of the cellulose and the polysaccharide on the extraction process is greatly reduced, and the extraction rate and the purity of the radix achyranthis bidentatae exosome are improved; in addition, the mycillin mixed solution can effectively resist microorganisms in plants by standing and precipitating the extracting solution in the extraction process, so that the physicochemical properties of the exosome are stabilized, and the preservation time of the exosome is prolonged. Meanwhile, medicine residues filtered in the extraction process can be recycled, environmental pollution is reduced, and the scientific research cost is reduced.

The invention discloses a cartilage cell targeting recombinant adeno-associated virus and a preparation method thereof, and belongs to the technical field of gene engineering. The recombinant adeno-associated virus is obtained by co-transfecting an HEK293 cell by using a recombinant plasmid pSSCMV-Cl2a1-SOX9 and a helper plasmid; and the recombinant plasmid pSSCMV-Cl2a1-SOX9 is obtained by inserting a fusion gene of Col2a1 and SOX9 into a pSSHG-CMV carrier. The preparation method comprises the following steps: step 1, constructing a recombinant plasmid pSSCMV-Col2a1-SOX9, and constructing the recombinant plasmid pSSCMV-Col2a1-SOX9; step 2, culturing the HEK293 cells, and waiting for transfection; and 3, co-transfecting the recombinant plasmid pSSCMV-Cl2a1-SOX9 obtained in the step 1, a pHelper plasmid and a pAAV-RC plasmid into the HEK293 cell cultured in the step 2, culturing, collecting a cell lysis solution, and carrying out iodixanol gradient centrifugation combined with Heparin chromatographic purification to obtain the recombinant adeno-associated virus. The recombinant adeno-associated virus obtained by the invention has targeting property and higher expression level.