213results about How to "Gentle preparation" patented technology

The invention belongs to the technical field of a composite fiber material, in particular relates to a poly-dopamine based porous carbon fiber / MoSe2 nanosheet composite material and a preparation method thereof. The method comprises the following steps of preparing a spinning solution with a spinnable high-polymer material, and preparing to obtain porous fiber with an uniform structure by an electrostatic spinning device; immersing the porous fiber in a dopamine solution, and controlling the thickness of a poly-dopamine cladding layer by adjusting the concentration and the reaction time of the dopamine solution; carrying out high-temperature carbonization to achieve carbonization on the poly-dopamine modified porous fiber material; and uniformly arranging MoSe2 nanosheets on the surface of the porous fiber by a hydrothermal method. The method disclosed by the invention is safe and environment-friendly, and the prepared porous carbon fiber / MoSe2 has the advantages of high active substance content, high specific area, high conductivity, stable physical and chemical performance and the like, and is an ideal electrode material for preparing an active electric catalyst for a hydrogen evolution reaction.

The invention relates to a method for preparing copper-titanium dioxide core-shell nanoparticles. In the method, cupric ions provided by cuprous chloride are dissolved into ammonia water; an aqueous solution of polyethylene glycol, an aqueous solution of sodium citrate, an aqueous solution of ascorbic acid, a solution of tetrabutyl titanate (absolute ethyl alcohol) and urea are sequentially addedinto the ammonia water; the ammonia water is put into a teflon-lined stainless steel autoclave after the ammonia water is stirred at room temperature; and the nearly-spherical core-shell nanoparticles are prepared through controlling the temperature and the time for the thermal reaction of the mixed solvents. In the method for preparing the copper-titanium dioxide core-shell nanoparticles, the ascorbic acid serves as a reducing agent and is used for reducing the cuprous ions; and the polyethylene glycol serves as a soft template. The method for preparing the copper-titanium dioxide core-shellnanoparticles has the advantages of simple process, environment-friendliness, low cost and the like; the outer layer of each of the prepared copper-titanium dioxide core-shell nanoparticles is anatase titanium dioxide, and the inner layer of each of the prepared copper-titanium dioxide core-shell nanoparticles is cubic-phase copper elementary substance; and the size distribution is even, and the particle size is controllable, thus the copper-titanium dioxide core-shell nanoparticles can be used as the electrode materials and the photocatalyst materials of dye-sensitized solar cells.

The invention discloses a preparation method of a graphene / titanium dioxide photocatalyst, which comprises the following steps of (1) preparing a solution A, slowly adding tetrabutyl titanate into chloroform, and obtaining the solution A, (2) preparing a mixed solution B, adding oxidized graphene into a mixed solution of deionized water and ethanol, and obtaining the mixed solution B, (3) stirring the mixed solution B, adding the mixed solution B into the solution A simultaneously, stirring uniformly, and obtaining a mixed solution, and (4) placing the mixed solution into a hydrothermal kettle, conducting the hydrothermal treatment, naturally cooling to a room temperature, separating and washing, and obtaining the graphene / titanium dioxide photocatalyst. The graphene / titanium dioxide photocatalyst prepared by the method has an excellent photocatalytic degradation property for organic dye.

The invention discloses a method for preparing a porous polymer micro needle by using a template method and an application thereof. The method comprises the following steps of: (1) dissolving a polymer and a template agent in a solvent to prepare a polymer solution; (2) filling the polymer solution into a micro needle mould; (3) removing the solvent in the obtained micro needle mould to obtain a solid micro needle; (4) removing the template agent in the obtained solid micro needle to obtain the porous polymer micro needle. By improving the overall process flow design of the preparation method,the method can solve the technical problems of a complex preparation process, harsh conditions, a complicated process, high price, difficult control of the pore structure and size, difficult large-scale production and application and the like of the porous polymer micro needle, the obtained porous polymer micro needle can be used for tissue fluid extraction and transdermal administration, such asskin tissue fluid and blood extraction and transdermal administration of proteins, polypeptides and small molecular drugs in cosmetic, hair growth, immunity, treatment and other applications.

The invention discloses a vaccine for prevention and treatment, wherein the antigen is in two forms with one absorbed on a biodegradable polymer particle and the other unabsorbed (free antigen). The average grain diameter of the particles is 0.1-20um; the antigen has specific structure and antiviral effect, preferably hepatitis B surface antigen and vaccines used for human being. The vaccine is prepared by the following methods: mixing polymer particles with antigen solution to obtain suspension under the absorption of the polymer particles and antigen solution, that is vaccine product; and adding cryoprotector in the obtained suspension-like vaccine to obtain lyophilized powder of the vaccine. The vaccine can induce immune response rapidly in the engine body, induces the engine body to generate high-level humor immune and cell immune, and eliminates or controls virus by secretoryantibody or cytokine. Besides, the vaccine has simple preparation process and mild preparation process.

The invention relates to a multifunctional polyethylene glycol-dual vitamin E succinate derivative and application thereof in drug delivery. An amphiphilic block copolymer utilizes polyethylene glycol as a hydrophyllic end to be combined with bimolecular hydrophobic vitamin E succinate under bridging of lysine, so that the AB2 type two-arm amphiphilic block copolymer is obtained. The polymer has potential antineoplastic activity and P-gp inhibitory action, and is capable of synergetically and effectively overcoming multidrug resistance to increase chemotherapeutic effect. Besides, the block copolymer can be self-assembled to form a micelle in aqueous medium, and can serve as a reservoir of poorly water-soluble drug, protein and gene-based drug, and the micelle is safe and high in stability and encapsulation, can be used for intravenous injection and oral ingestion, and has bright market application prospects.

The invention discloses a preparation method of a graphene / titania composite material, which comprises the steps of preparing a precursor solution, and heating and stirring the precursor solution and the like. The preparation method of the graphene / titania composite material has the beneficial effects: the process is simple, the implementation is easy, and the opportunity of introducing impurities is reduced, so that the purity of a product can not be affected. The preparation process is mild without protection of a special atmosphere, the required equipment is simple, the reaction speed is quick, and the preparation method is suitable for mass production. Graphene oxide can be reduced by microwave heating, and a toxic reductant is not used.

The invention relates to a preparation method of a porous scaffold material and discloses a preparation method of a nano-fibrous silk fibroin-based porous scaffold. The preparation method comprises the following steps: blending a silk fibroin solution and a collagen solution under the temperature of 0-20 DEG C, standing to ensure the complete reaction of collagen and silk fibroin and generate nano-fiber; freezing the mixed solution to obtain a freezing body; performing freeze drying treatment on the freezing body to obtain a nano-fibrous porous scaffold material; and placing the nano-fibrous porous scaffold material in a vacuum drier with water and methanol, or an ethanol aqueous solution at the bottom, vacuumizing, and then standing to obtain the water-insoluble nano-fibrous porous scaffold. The obtained porous scaffold has 10-1000 microns of communicated pores. The pore walls consist of 10-100nm of nano-fibers; and the porous scaffold has similar nanoscale structures and micronscalestructures to extracellular matrix, is suitable for the adhesion and growth of cells and has good biocompatibility.

The invention relates to preparation and application of medicine-carrying polydopamine / dendrimer-gold nanoparticles. The preparation comprises the steps of modifying dendrimer-gold nanoparticles to the surfaces of polydopamine nanoparticles, and performing polyethylene glycol modification and anticancer medicine adriamycin loading. Obtained composite nanoparticles having a core-satellite structurecan be subjected to acid response to release minisize satellites, medicine delivery in deep tumors is realized, and medicine tolerance generated by tumor hypoxia is relieved; and adriamycin is released at a fixedpoint under internal (acid and hydrogen peroxide) and external (near infrared light) stimulation. The obtained composite nanoparticles have favorable biocompatibility, can realize optoacoustic diagnosis and photothermal treatment on tumor locations, and what's more, can realize remarkable restraining effects on tumor growth. Through the adoption of the method disclosed by the invention, the treatment effects of traditional chemical medicines can be notably improved, more comprehensive three-dimensional tumor treatment is realized, and a new thinking is provided for diagnosis and treatment of malignant tumors.

The invention provides a method for preparing a nanoscale granular W18O49 material. The method comprises the steps of adding WC16 into absolute ethyl alcohol to prepare a solution A; adding oxalic acid into the solution A to obtain a solution B, wherein the mass ratio of the oxalic acid to the WC16 to is (5 to 10) to 1; sealing the solution B, stirring, and then performing ultrasonic treatment, so as to obtain a solution C; enabling the solution C to react in a homogeneous reactor, and obtaining the nanoscale granular W18O49 material after the reaction. The prepared homogeneously dispersed nanoscale granular W18O49 material is uniform in chemical constitution, high in purity, and uniform in shape, and the W18O49 is a nano-particle with the diameter being 20nm. The W18O49 material has relatively large specific surface area, and more active crystal faces are enabled to exposed at the same time, so that catalytic efficiency is greatly improved. The reaction temperature is low, the condition is mild, the energy consumption is less, the preparation process is simple, the cost is lower, the process is easy to control, the preparation period is short, and the method is easy to implement and is friendly to environment.

The invention discloses a nanometer cellulose / polydopamine compound intelligent gel drug sustained-release material and a preparation method thereof. The drug sustained-release material comprises nanometer cellulose, polydopamine and a drug loaded on the polydopamine, can be applied to the field of various drug sustained release and is especially suitable for the aspects of wound treatment, tumor postoperative treatment, and the like. The drug sustained-release material disclosed by the invention can load hydrophilic and hydrophobic drugs, is simply prepared, is mild and is capable of saving cost. The nanometer cellulose and the polydopamine both have biocompatibility, can completely degrade, are easy for waste treatment and are beneficial to environmental protection. The drug sustained-release material is especially suitable for wound healing and later treatment of tumor operation.

The invention provides a clean preparation method of a magnalium based laminated composite hydroxide. The method uses magnesium hydroxide, magnesium oxide, pseudo boehmite, inorganic acid and a material containing functional anions as raw materials, uses magnesium chloride or magnesium nitrate as a circulation medium, and uses the property of peptization under acidic condition of boehmite to improve the reaction activity of pseudoboehmite; the concentration of magnesium ions in solution is increased by using magnesium chloride or magnesium nitrate. The method accelerates the formation rate of laminated composite hydroxide, promotes the dissolution of magnesium hydroxide and magnesium oxide, shortens the reaction time, overcomes the defects of high reaction temperature and long time consumption in hydrothermal method for synthesis of laminated composite hydroxide, and can rapidly prepare magnalium based laminated composite hydroxide under mild conditions. Magnesium chloride and magnesium nitrate can be recycled; and the preparation process has no waste discharge, and is green and environment-friendly. The method has the advantages of abundant raw materials, low cost, simple preparation process, mild reaction conditions, and easiness to industrial production.

The invention belongs to the technical field of medicines and discloses melittin complex nanoparticles for oral administration and a preparation method thereof. Water-soluble melittin and an amphiphilic substance are dissolved into a hydrosolvent A to form a hydrophobic protein ion pairing complex; the complex and a suitable polymer material are dissolved into a nonaqueous solvent B; an emulsion solvent diffusion method in a liquid phase is adopted to wrap the complex into the polymer material; and microparticles with the particle diameter between 10 and 1000nm are formed after the solvent is volatilized. The hydrosolvent A is distilled water, double distilled water, deionized water, physiological saline, or a phosphate buffer solution or an acetate buffer solution or a Tris buffer solution with the pH value of between 1 and 11; and the nonaqueous solvent B is a single or mixed solvent of alcohol, acetone, ethyl acetate, methylene dichloride, chloroform and dimethyl sulfoxide. The complex has high fat solubility, and the encapsulation rate of the nanoparticles is more than 90 percent. The preparation process is mild and can assure the biological activity of medicines. The preparation method is suitable to prepare oral administration preparations.

The invention provides gel-in-oil-in-water emulsion as well as a preparation method and an application thereof. The gel-in-oil-in-water emulsion comprises an internal gel phase, an oil phase and an external water phase, wherein the internal gel phase is coated with the oil phase which is coated with the external water phase. The gel-in-oil-in-water emulsion can be used as a delivery carrier for human or animals, the internal gel phase has good biocompatibility, can be prepared under mild conditions and has environmental stimulus response, a multiple emulsion structure is prepared under mild conditions, and poor stability of multiple emulsion is improved greatly; efficient loading and activity retention of hydrophilic and hydrophobic substances especially bioactive substances can be realized, the condition that in-situ gel can only realize local drug delivery is improved, and the gel-in-oil-in-water emulsion can realize targeted delivery and intelligent controllable release on human andanimals and has extensive application prospects in the fields of vaccine adjuvant preparation, sustained and controlled drug release, targeted drug delivery, disease diagnosis and daily chemical products.

The invention relates to a new green synthesis method for efficient formation of a C-C bond on an aromatic (heterocyclic) ring and cyclization into isoquinoline derivatives by transition metal catalyzed C-H activation / cyclization reaction and use of water as a solvent and sulfur ylide as a carbene donor. Compared with the traditional method, the method provided by the invention has the characteristics of easily available raw materials, simple steps and no use of toxic organic solvent, is a mild, rapid, simple, effective and environment-friendly method for preparation of isoquinoline mother ring, and has broad application prospects.

The invention belongs to the technical field of nano-fiber materials, in particular to a pure carbon fiber material adopting a 'vesical string' structure and a preparation method of the pure carbon fiber material. The preparation method comprises the following steps: preparing a spinning solution from a spinnable polymer material, and preparing nanofibers of uniform structures with an electrostatic spinning device; uploading iron oxide hydroxide cambiform nanorods on the surfaces of the nanofibers uniformly via a water bath or hydrothermal method; soaking an iron oxide hydroxide-modified fiber membrane in a dopamine solution, and controlling the thickness of a polydopamine coating layer by adjusting the concentration of the dopamine solution and the reaction time; carrying out high-temperature carbonization treatment, so as to realize fiber carbonization, and conversion of iron oxide hydroxide to ferroferric oxide as well as polydopamine to a N-doped carbon material; removing ferroferric oxide via soaking in an acid solution. The preparation method is safe and environmentally friendly; the prepared pure carbon fiber material is high in nitrogen content, specific surface area and electric conductivity, and stable in physical and chemical properties, so as to be an ideal electrode material for production of new energy devices such as a supercapacitor.

The invention provides a method for preparing ellipsoid-shaped zinc oxide. The method comprises the following steps of: dissolving a certain amount of zinc slat in water, and stirring the mixed solution until the mixed solution is clear; heating the mixed solution up to between 50 and 100 DEG C, dripping an alkali solution into the mixed solution when the mixed solution is stirred until the pH value of the mixing solution is between 6 and 14, and obtaining a white precipitate; filtering, washing and drying the white precipitate to obtain the finished product. The method has the advantages that: (1) only two raw materials are needed in the whole preparation process, other reaction raw materials are unnecessarily added, and the chance of introducing impurities is lowered, so that the purity of products is not affected; (2) the whole preparation process is mild, the conditions of high temperature, special atmosphere protection and ultrasonic and microwave assistance are not needed, so that the needed equipment is simple, the reaction speed is fast, and the method is more suitable for mass production; and (3) the prepared ellipsoid-shaped zinc oxide has uniform size and good dispersity. By adjusting concentrations of the raw materials, the ellipsoid-shaped zinc oxide of which the sizes of the long shaft and the short shaft are between 50 and 1,000nm can be obtained.

The invention relates to the technical field of selective photocatalytic oxidation synthesis, which more particularly relates to a semiconductor TiO2 photocatalyst modified with promoter on the surface and the corresponding preparation method, as well as the catalyst application on the selective oxidation of primary alcohol or secondary alcohol to Aldehyde or Ketone. The invention is designed to perform chemical treatment on the TiO2 surface to convert the TiO2 into organic nitro-oxy radical which can highly selectively react with the primary or secondary alcohol to obtain the corresponding aldehyde or ketone as for the selectivity of stereo-hindrance, through an in-situ conversion of photo-excited holes. The selective conversion rate to any hydrin by the catalyst in the invention can achieve up to 99%, while commonly the conversion rate is over 90%, particular to the aromatic alcohol e.g. benzyl alcohol of over 99% of selectivity; both the catalyst and promoter can be reused for times through simple filtration, have long life without carbon deposition; the conditions of both preparation and reaction are mild.

The invention provides a modified transition metal base-layer dihydroxy compound nano material, which comprises two or three transition metals, and further comprises an atomic level cation vacancy defect, the atomic level cation vacancy defect is a vacancy defect left by removing of one of the transition metals. The invention also provides a preparation method of the nano material through complexation reaction, and the preparation method can selectively remove designated metal ions to controllably form the atomic level cation vacancy defect at the atomic level, and has simple operation and mild reaction. The nano material and a water decomposition catalyst and a water decomposition electrode containing the nano material show lower decomposition water overpotential and faster hydrogen production rate, and have wide application prospect in efficient and cheap large-scale commercial water decomposition hydrogen production.

The invention provides a novel preparation method of a tumor targeting nano-preparation of nanoparticles based on a a core-shell structure, wherein folic acid and polyethylene glycol double-modified chitosan is used as the shell material, and a small-molecular chemotherapeutics drug is entrapped in the core by a coaxial electrospray technique. Compared with a traditional preparation method, the method provided by the invention is short in preparation period, simple, mild in preparation process, and overcomes disadvantage of conventional preparation technique that is unable to prepare nanoparticles with the core-shell structure. The nanoparticles with the core-shell structure overcomes the disadvantages that the small-molecular chemotherapeutics are adsorbed on the surfaces of the nanoparticles mainly relying on the physical interaction with chitosan, causing low drug-loading rate and entrapment efficiency, the drug is apt to burst release, the blood circulation time is short, and the drug intake is insufficient for tumor tissues; and the nanoparticles with the core-shell structure can be mediated by commonly overexpressed folate receptors of malignant tumors and are suitable for targeted therapy of various tumors.

The invention relates to a method for preparing a mesoporous AgGaO2 photocatalytic material. The mesoporous AgGaO2 photocatalytic material is prepared through two steps. Firstly, mesoporous AgGaO2 is prepared by the utilization of the sol-gel method, and then, the prepared AgGaO2 is used as a raw material to be synthesized to form AgGaO2 through the ion exchange method. The method has the advantages of being unique in technology and convenient to operate. The prepared mesoporous AgGaO2 is large in specific surface area, adjustable and controllable in pore structure and high in photocatalysis activity, and has broad application prospects in the fields such as indoor air purification. The method for preparing the mesoporous AgGaO2 photocatalytic material can provide a new idea for optimization design and large-scale preparation of other novel polybasic metallic oxide photocatalytic materials containing silver.

The invention relates to a large Pi system polyimide cross-linked polymer for a negative electrode of a lithium ion battery. Common polyacyl conjugated molecules which are used as a raw material and a polyamino compound are subjected to thermal polycondensation to form the stable large Pi system cross-linked polymer. The large Pi system polyimide cross-linked polymer prepared through thermal polycondensation shows excellent electrochemical performance when applied to a negative electrode of the lithium ion battery; in addition, the problem of heavy metal pollution caused by a traditional lithium ion battery negative material can be avoided; in structure, the large Pi system polyimide cross-linked polymer is relatively high in structure element conjugation degree and structure rigidity and is capable of improving battery capacity due to existence of a large quantity of imide groups; therefore, a formed three-dimensional network structure is relatively good in electrical conductivity and structure stability and can be applied to development of a lithium ion battery with high cycling stability and long cycling life.

The invention provides a tissue engineering scaffold with multi-growth-factor sequential release characteristic, and belongs to the technical field of dosage form variation and preparation method. In the tissue engineering scaffold, together with the characteristics of microspheres sustained release system and scaffold, PLLA / PEG (poly-lactic acid / polyethylene glycol) sustained release microspheres of growth factors such as BMP-2 (bone morphogenetic protein), VEGF (vascular endothelial growth factor), bFGF (basic fibroblast growth factor) are prepared respectively by the multiple emulsion method, so as to construct the tissue engineering scaffold with multi-growth-factor sequential release characteristic. The method is high in drug activity maintaining degree, low in organic solvent residue and easy to operate. The prepared microspheres are narrow in particle size distribution and have an excellent sustained release effect. The pore size distribution of the composite scaffold is 150-300mu m, the connectivity is excellent, the porosity is 76.84%, the compressive strength is 5.11MPa, and the accumulative release amount of 21 days is 60.6%. The scaffold prepared according to the invention has an application prospect in tissue engineering restoration.

The invention provides a preparation method of a calcium chloride cross-linked sodium alginate electrically-driven film. Sodium alginate and calcium chloride are subjected to cross-linking reaction according to certain mole ratio, then glycerinum is added to serve as a modifier, produced solution is subjected to ultrasonic defoaming and vacuum drying treatment and then produces the calcium chloride cross-linked sodium alginate electrically-driven film at one step. The method comprises steps of liquid phase cross-linking reaction, ultrasonic defoaming treatment and high-temperature drying. Themethod is green and environmentally friendly, low in cost, simple in steps, and suitable for large-scale production, ensures that the produced sodium alginate electrically-driven film can replace thetraditional driving structure in the field of flexible machinery and has good tensile strength and flexibility.

A chitosan microsphere or microcapsule is prepared through proportionally mixing oil phase with surfactant, stirring, proportionally adding chitosan solution (water phase), stirring, proportionally adding ammonium sulfate solution, stirring, centrifugal separation of deposit, washing and drying.

The invention discloses selenium-enriched bacillus bifidus micro-capsules. The selenium-enriched bacillus bifidus micro-capsules are prepared by adopting a method comprising the following steps: uniformly mixing a sodium alginate solution with selenium-enriched bacillus bifidus thallus and calcium carbonate powder so as to obtain a mixture; dropwise adding the mixture into vegetable oil containingan emulsifier, and carrying out stirring so as to obtain an emulsion; sequentially adding vegetable oil containing glacial acetic acid and an emulsifier solution into the emulsion, carrying out stirring, and allowing standing; and then, separating oil phase so as to obtain aqueous phase, and centrifuging the aqueous phase so as to obtain the selenium-enriched bacillus bifidus micro-capsules. By screening reagents, materials and dosage ratio adopted in micro-capsule preparing, coating and freeze-drying processes, embedding rate of the selenium-enriched bacillus bifidus micro-capsules disclosedby the invention are improved. The embedding rate of the selenium-enriched bacillus bifidus micro-capsules is up to 98% while the particle size is smaller than 200 microns and the freeze-drying survival rate is up to 85%. According to normal-temperature stability results, viable number of the selenium-enriched bacillus bifidus micro-capsules is still about 10<8> cfu / g within 180 days.

The invention relates to a preparation method for oily and oil soluble drug nanocapsules, and aims at solving the problem that the existing nanocapsules prepared by the existing method have low packing efficiency and are large in grain size. The preparation method comprises the following steps of 1. preparing gelatin solution and chitosan solution; 2. preparing O / W emulsion with grain size of nanoscale; 3. adding the chitosan solution into the O / W emulsion with grain size of nanoscale so as to obtain mixed liquor; and 4. regulating pH value of the mixed liquor so as to obtain compound condensate, diluting the compound condensate and adding a curing agent, and then drying so as to complete the preparation of oily and oil soluble drug nanocapsules. The preparation method for oily and oil soluble drug nanocapsules is applicable to the technical field of medicines.

The invention discloses a photothermal-chemotherapy combined therapeutic agent based on Prussian blue and a preparation method of the therapeutic agent. The therapeutic agent is characterized in that the therapeutic agent is of a liposome-like structure, Prussian blue nanoparticles are used as a core, a medicine-carrying bimolecular layer is formed outside the core through hydrophobic-hydrophobic interaction between two different amphipathic surfactants, and anticancer medicine is encapsulated in the medicine-carrying bimolecular layer. The therapeutic agent combines Prussian blue with the anticancer medicine to realize photothermal-chemotherapy synergistic treatment, so that the problem that chemotherapy medicine is low in specificity and human body utilization rate is solved, the defect that photothermal treatment is incomplete is overcome, treatment efficiency is improved greatly, and the therapeutic agent has good clinical application prospect.

The invention relates to a preparation method of genipin crosslinked chitosan drug-loaded microspheres. The preparation method comprises the steps: after fully agitating water-insoluble oil-based substances with a surfactant evenly as an oil phase mixture by adopting an emulsion chemical-crosslinking method, adding a mixed solution with chitosan and loaded water-soluble drugs into the oil phase mixture as a water phase, fully agitating to an obtain a water-in-oil (W / O) type mixture, fully agitating and dropwise adding a crosslinking agent for crosslinking and curing through an injector, standing to remove the solution at the upper layer, centrifugally washing and drying the settling system at the lower layer respectively through an organic solvent to obtain the corresponding drug-loaded chitosan microspheres. The chitosan microspheres prepared by adopting the preparation method overcomes the defects and shortcomings existing in the traditional preparation method, are simple and easy in technique, low in toxic and side effects and high in mechanical strength, can be widely applied in the fields of food, biology, medical engineering and the like as a drug-use controlled-release carrier.

The invention relates to a catalyst containing a heteroatom-doped molecular sieve and a method for preparing low-carbon olefin by directly converting synthesis gas. The catalyst is a composite catalyst; a component I and a component II are compounded together in a mechanical mixing manner; wherein the active ingredient of the component I is a metal oxide; the component II is the heteroatom-doped molecular sieve; the molecular sieve has a topological structure of CHA or AEI, skeleton atoms comprise Al, P, O and Si, and heteroatoms can be one or more than two of ions from divalent Mg, Ca, Cr, Mn, Fe, Co, Ni, Cu, Zn, Sr, Zr, Mo, Cd, Ba, Ce, trivalent Ti, Ga and tetravalent Ge; the weight ratio of the active ingredient of the component I to the component II is in a range of 0.1-20 times. The reaction process has very high low-carbon olefin selectivity, the sum of the selectivity of low-carbon olefins including ethylene, propylene and butylene can reach 50-90%, meanwhile, the selectivity ofbyproduct methane is lower than 7%, and meanwhile, the method has a very good application prospect.