56results about How to "Degradation controllable" patented technology

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 discloses imitated extracellular matrix injectable in-situ hydrogel and a preparation method and application thereof. The hydrogel is prepared by carrying out a cross-linking reaction between sulfhydrylation gelatin, sulfhydrylation polysaccharides or RGD-containing cell adhesion peptides and polyethylene glycol diacrylate. The composition of the hydrogel is similar to that of the extracellular matrix, so that the hydrogel has high biocompatibility, has the effects of controlled degradation, controlled release and / or cell behavior regulation in performance and can conveniently meet the requirements on different release rates of growth factors or medicines. Meanwhile, the clinical injectable and in-situ forming operation requirements can be met, and the hydrogel has good application prospects in tissue repair and regeneration.

The invention aims to provide a biodegradable composite film material of controllable degradation rate with good mechanical property, faster and more through degradation and no environmental harm, and a preparation method thereof. The material comprises the following components in parts by weight: 100 parts of matrix resin, 0-40 parts of other biodegradable polymers, 0.5-1.5 parts of heat stabilizer, 0.3-5 parts of nucleating agent, 1-5 parts of compatilizer, 2-15 parts of plasticizer and 0.3-5 parts of opener. The matrix resin is obtained by mixing poly lactic acid (PLA) and 3-hydroxybutyrate-3-hydroxy acid copolyester (PHBH) with each 20-80 parts by weight. The other biodegradable polymers are poly butylenes succinate (PBS), poly propylene carbonate (PPC), 3-hydroxybutyrate-3-hydroxyvalerate copolyester (PHBV) and terephthalic acid-butanediol-adipic acid copolyester (PBAT).

The invention relates to a method for preparing a fish-skin collagen powder by the use of fresh fish skin. The method comprises the following steps: fresh fish skin is selected as a raw material and is immersed in sodium hydroxide, the fresh skin is washed with water to neutral pH after fat and impure protein on the surface of the fish skin are removed, and crushing is carried out; drinking water and edible vinegar are added to the crushed fish skin and uniform agitation is carried out, ultrasonication and deodorization treatments are carried out, and papain is added to carry out controlled-enzymatic hydrolysis so as to obtain a fish-skin enzymatic hydrolysate; active carbon is added for decarburization clarification after enzyme deactivation, filtration is carried out, and a filtrate undergoes concentration and spray drying so as to obtain the fish-skin collagen powder. By ultrasonication of the fish skin, active ingredients in acetic acid are activated to react with fishy smell substances in the fish skin so as to remove the fishy smell. By adding active carbon into the enzymatic hydrolysate to carry out decarburization clarification for fishy smell elimination and decoloration, the prepared fish-skin collagen powder has no fishy smell. The method provided by the invention has advantages of advanced technology, reasonable process and controllable operation, and is suitable for large-scale production.

The invention discloses a preparation method of collagen sponge. The method comprises the following steps: carrying out enzymolysis on cattle heel tendon in protease aqueous solution at pH value of 1.0-5.0; centrifuging the enzymolysis liquid, collecting supernatant, and salting out collagen with saturated salt solution; dialyzing salted-out collagen; cross-linking the dialyzed collagen in a cross-linking agent aqueous solution; and freeze-drying cross-linked collagen gel, cross-linking the collagen in a cross-linking agent aqueous solution and freeze-drying to obtain the collagen sponge. The collagen sponge obtained by the preparation method of the collagen sponge disclosed by the invention has certain elastic and tensile toughness after being immersed in water, and has good biocompatibility and tissue repairing performance, and high protein content and is controllable in degradation.

The invention relates to a preparation and application of a stitchable dura mater repairing material, and belongs to the field of a biomaterial and medical treatment and public health. The invention specifically discloses a preparation and application of a stitchable dura mater repairing material. The preparation comprises: extraction of target collagen, preparation of a compact layer, preparationof a porous layer, freeze-drying of dura mater, crosslinking and sterilization. The dura mater repairing material has a double-layer composite structure, and is good in mechanical property, is stitchable, and can effectively prevent bleeding of a cerebrospinal fluid. The material is high in purity and has a triple helical structure integratedly maintained in the compact layer. The material is good in biological activity and biological compatibility and controllable in degradation, and is a good substitute for cerebral dura mater and spinal dura mater.

The invention discloses a method for preparing alpha-calcium sulfate hemihydrates (alpha-CSH) / beta-tertiary calcium phosphate (beta-TCP) porous granular-type composite artificial bones, which is characterized in that the alpha-CSH is directly synthesized on the surface and / or in the pores of the beta-TCP granules synchronously by the hydrothermal synthesis process and finally the alpha-CSH / beta-TCP porous granular-type artificial bones is prepared. The invention has the advantages that the preparation process is simpler, the preparation period can be effectively reduced, and the preparation efficiency is improved; the proportion between alpha-CSH and beta-TCP phases of the granular-type composite artificial bones can be effectively controlled, thereby controlling the pore structure of the artificial bone granules; meanwhile, the invention guarantees the in-situ solidifying performance and degrading performance of the composite artificial bones, controls the evenness of the product and the porosity and pore diameter of the beta-TCP granules, improves the bone-formation performance and degrading performance of the composite artificial bones and further improves the quality of the product, thereby finally obtaining the composite artificial bones having self-solidifying performance and controllable degradation and having a certain biomechanical strength. The invention has good application and market prospect.

The invention relates to a degradation controlled tissue engineering comea fibrous scaffold and a preparation method thereof. The basic compositions of the scaffold are gelatin and aliphatic polyesters. The preparation method comprises the following steps: dissolving the gelatin in a mixed solvent to prepare gelatin solution, dissolving the aliphatic polyesters in the gelatin solution, and evenlystirring to prepare mixed polymer spinning solution; and preparing the orderly and disorderly arranged fibrous scaffold through electrostatic spinning, and performing vacuum drying to prepare the degradation controlled tissue engineering comea fibrous scaffold. The gelatin and aliphatic polyesters compounded electrostatic spinning is adopted, crosslinking stabilization is not needed, and the degradation speed of the scaffold and growth speed of corneal cells can be controlled to be synchronous. The product has transmittance of 97 percent, wet tensile strength of 4.91MPa, elongation at ruptureof 956.2 percent, water content of 154.1 percent, and performance parameters similar to human comea, and has good bioactivity and biocompatibility, has controlled degradation and no toxicity, is favorable for adhesion and growth of the cells, and has certain strength and toughness, simple preparation process, low cost and easy wide application.

The invention relates to a preparation method of oxidized nano bacteria cellulose, belonging to the related fields of biomedical materials and medical appliances. The method comprises the following steps: performing pretreatment and purification treatment on nano bacteria cellulose film to obtain purified nano bacteria cellulose, and shearing into wafers or square slices of different specifications; placing sheared nano bacteria cellulose in a clean wide-necked bottle or a wide-necked bottle holding a nitric acid solution with appointed concentration, and introducing NO2 / N2O4 gas generated by reaction between copper powder and concentrated nitric acid to the wide-necked bottle so as to oxidize the nano bacteria cellulose; and taking out the sample after appointed time, and repeatedly cleaning with deionized water to obtain oxidized nano bacteria cellulose containing carboxyl group on C6 position. The prepared oxidized nano bacteria cellulose has excellent degradation property, biocompatibility and cellular affinity, excellent bleeding arresting performance and mechanical properties, and excellent water permeation, gas permeation, guiding and moisture absorption effects, and has higher application value in the aspects of implantation materials and wound bleeding arresting materials.

The invention discloses a composite collagen biological membrane and a preparation method thereof. Collagen in the composite collagen biological membrane is of a triple-helical structure; the composite collagen biological membrane is 0.2 to 0.9 cm in thickness, and is of a three-dimensional pore structure; the aperture of a multihole layer is 60 to 400 microns, and the aperture of a compact layer is 100 to 900 microns. The composite collagen biological membrane provided by the invention is formed by combining the compact layer with a relatively high collagen density and the multihole layer with relatively high porosity, so that the composite collagen biological membrane is high in mechanical strength, has suturing property and the advantages of biodegradability and low immunogenicity, and can be used as a substitute for an endocranium, a spinal membrane and the like.

The invention discloses an efficient degradation strain JN1 of petroleum hydrocarbons in oily sludge and application thereof, and belongs to the technical field of biological restoration. The degradation strain JN1 is preserved in CGMCC (China General Microbiological Culture Collection Center), has the preservation number of CGMCC NO.14972, and has the classification number of Acinetobacter sp.. The purpose of the strain JN1 with the petroleum hydrocarbon degradation function is the oily sludge control performed in a petroleum hydrocarbon degradation mode. The degradation rate of a single strain of the bacterium in 30 days on the TPH in the oily sludge is 58.05 percent; the most proper degradation conditions of the bacterium on petroleum contaminants are the follows: the temperature is 25to 50 DEG C and the pH value is 5 to 7. The biological method is used for the restoration technology of the oily sludge, and has the advantages of high efficiency, low cost, environment-friendly effect and the like.

The invention discloses a calcium sulfate hemihydrate / octacalcium phosphate / carboxymethyl chitosan composite artificial bone material and a preparation method thereof. An injectable composite artificial bone material comprises a curing liquid and calcium sulfate hemihydrate / octacalcium phosphate / carboxymethyl chitosan composite powder, the curing liquid and the calcium sulfate hemihydrate / octacalcium phosphate / carboxymethyl chitosan composite powder are stored separately, the mass ratio of calcium sulfate hemihydrates to octacalcium phosphate to carboxymethyl chitosan is 1:0.01-0.5:0.01-0.1, the volume mass ratio of curing liquid to calcium sulfate hemihydrate / octacalcium phosphate / carboxymethyl chitosan composite powder is 0.3-1.0:1ml / g; and the curing liquid is an oxidized polysaccharide solution. Compared with various artificial bone materials in the prior art, the calcium sulfate hemihydrate / octacalcium phosphate / carboxymethyl chitosan composite artificial bone material has the advantages of simple preparation process, easy operation, good injection property and controllable composite material components, by compounding of traditional inorganic bone materials and a natural polymer material, defect part loss of in artificial bone injection initial stage can be prevented, and the calcium sulfate hemihydrate / octacalcium phosphate / carboxymethyl chitosan composite artificial bone material has the advantages of good mechanical strength, good biocompatibility and osteogenic properties, and controlled degradation.

The invention discloses a tissue engineering bracket applicable to human body organ construction, and the tissue engineering bracket has the bore diameter of 5 mu m-200 mu m, good bore connectivity and proper degradability, and can be applicable to growth of cells in the bracket. The invention further discloses a preparation method of the tissue engineering bracket applicable to human body organ construction. The preparation method comprises the following steps: firstly preparing sericin liquor, chitosan liquor and sodium glycerophosphate liquor into mixed liquor; then, converting the mixed liquor into a gel state; finally, obtaining the tissue engineering bracket by virtue of a process comprising freezing and drying, placing and softening, and high-pressure steam treating. By regulating the ratio of the sericin liquor, chitosan liquor and sodium glycerophosphate liquor or changing process conditions, the bore diameter size and degradation performance of the obtained tissue engineering bracket can be obtained in a controlled manner, so that the tissue engineering bracket satisfies the requirements of the tissue engineering bracket applicable to human body organ construction. The preparation method has the advantages of being gentle in reaction condition, simple in process and low in material cost, and is suitable for industrial scale-up production.

The invention relates to a preparation method of a controlled degradable magnesium alloy fixing screw in vivo and belongs to the technical field of medical apparatus and instruments. The preparation method of the controlled degradable magnesium alloy fixing screw in vivo comprises the following steps: firstly, processing a screw body by using magnesium alloy; secondly, forming an oxidation film layer with the thickness of 50 to 200mu m through the alternating current oxidation technology on the magnesium alloy screw body; thirdly, carrying out dip-coating or spraying of a biodegradable polymercoating which has the thickness of 1 to 50mu m on the oxidation film layer. The magnesium alloy fixing screw disclosed by the invention can be controlled and degraded in vivo; in addition, the strength retention period of the fixing screw is about 3 months and the degradation period can be controlled at about 6 to 8 months, so that the magnesium alloy fixing screw is suitable for fixing tissues or tissues and repair materials, and is especially suitable for repairing soft tissue defects such as hernia.

The invention relates to the technical field of marine antifouling coatings, in particular to a preparation method and application of biodegradable antifouling resin. The preparation method comprises the steps that raw materials including lactic acid, polyhydric alcohols and / or polyester polyol, a catalyst and a solvent A are adopted to synthesize a biodegradable polylactic acid block polymer P1; raw materials including the P1, triethylamine, methylacryloyl and a solvent B are adopted to synthesize polylactic acid block polymer based acrylic ester, raw materials including the P2, a metacrylic acid ester monomer, an initiator and a solvent C are adopted to synthesize a biodegradable acrylate polymer P3. The prepared biodegradable antifouling resin can be applied to the preparation of degradable antifouling coatings, the prepared antifouling coatings have excellent resistance to immersing in seawater and controllable degradability, then release of an antifouling agent is controlled, and a long-term antifouling effect is achieved.

The invention relates to a preparation method for a fruit and vegetable flavored seafood seasoning. The preparation method comprises the following steps: selecting dry swimming bladders as a raw material, carrying out the ultrasonic treatment after cleaning, crushing and soaking, adding in papayotin for enzyme-controlled enzymolysis after beating, adding in activated carbon for carbon removing after enzyme inactivating, and filtering through a filtering cloth to obtain an enzymolytic filtering solution; selecting fruits and vegetables to be cut into pieces, adding water in a reaction kettle, heating, extracting, and carrying out centrifugal filtration to obtain a fruit and vegetable extracting solution; mixing the enzymolytic filtering solution and the fruit and vegetable extracting solution, adding in monosodium glutamate, salt, disodium nucleotide and potassium sorbate, dissolving and uniformly stirring to obtain a seasoning solution; subpacking the seasoning solution into bottles to obtain the finished liquid fruit and vegetable flavored seafood seasoning, or carrying out spray drying on the seasoning solution to obtain the powdery fruit and vegetable flavored seafood seasoning. The preparation method is reasonable in technology, controllable in operation, short in preparation time and suitable for industrialized production; the prepared fruit and vegetable flavored seafood seasoning is rich in fruit and vegetable flavor, delicious in seafood taste, abundant in nutritions and easy to digest and absorb by a human body.

The invention relates to a magnesium alloy fixing screw capable of being degraded under control in vivo, belonging to the technical field of medical instruments. The magnesium alloy fixing screw capable of being degraded under control in vivo comprises a magnesium alloy screw body on which an oxidation film layer with a thickness of 50-200 microns is formed, and the oxidation film layer is coatedwith a degradable polymer coating with a thickness of 1-50 microns. The magnesium alloy fixing screw can be degraded under control in vivo, the strength maintaining period of the fixing screw is about3 months, the degradable period can be controlled within about 6-8 months, and the fixing screw is suitable for fixing between tissue and tissue or between the tissue and a patching material, and particularly suitable for repairing coloboma of soft tissue such as hernia.

The invention relates to a method for preparing a fish-skin collagen powder by the use of dry fish skin. The method comprises the following steps: dry fish skin is selected and is immersed in water for two times, and edible hydrochloric acid is added during the second immersion so as to remove impure protein on the surface of the fish skin; the fish skin is washed with water to neutral pH; drinking water and edible vinegar are added after crushing, and then ultrasonication and deodorization treatments are carried out; papain is added to carry out controlled-enzymatic hydrolysis so as to obtain a fish-skin enzymatic hydrolysate; activated clay and a flocculating agent are added after enzyme deactivation, static settlement is carried out, and hydroxyapatite impurities in the fish skin are removed; and a supernatant is taken and active carbon is added for decarburization clarification, and filtration, concentration and spray drying are successively carried out to obtain the fish-skin collagen powder. The method provided by the invention has advantages of advanced technology, reasonable process and controllable operation, and is suitable for large-scale production. By the method, the prepared fish-skin collagen powder has no fishy flavor and has high purity.

The invention relates to a preparation method for fragrance flavor seafood seasoning. The seasoning is prepared by implementing the following steps: taking dried swim bladder as a raw material; after washing and smashing, soaking the swim bladder, processing with ultrasonic waves and adding water to obtain swim bladder seriflux; adding papayotin into the seriflux for enzymolysis; killing enzyme; adding activated carbon for carbon removal and filtering the mixture to obtain enzymolysis filter liquid; adding water into a reactor filled with ginger powder, reducing sugar, vitamin B1 and five spice powder, heating, extracting, cooling and performing centrifugal filtering to obtain flavor liquid; mixing the enzymolysis filter liquid with the flavor liquid first and adding gourmet powder, salt, Disodium 5'-ribonucleotide and potassium sorbate for blending to obtain seasoning liquid; packaging the seasoning liquid into different bottles to obtain liquid state flavor seafood seasoning finished products or performing spray drying on the seasoning liquid to obtain powdery fragrance flavor seafood seasoning. The preparation method provided by the invention is reasonable in technology, controllable in operation, scientific in sorting and short in preparation time; the seasoning prepared by the preparation method is rich in spiced flavor, natural in seafood taste, intense in fragrance, rich in nutrition and easy to digest and absorb by human body.

The invention discloses imitated extracellular matrix injectable in-situ hydrogel and a preparation method and application thereof. The hydrogel is prepared by carrying out a cross-linking reaction between sulfhydrylation gelatin, sulfhydrylation polysaccharides or RGD-containing cell adhesion peptides and polyethylene glycol diacrylate. The composition of the hydrogel is similar to that of the extracellular matrix, so that the hydrogel has high biocompatibility, has the effects of controlled degradation, controlled release and / or cell behavior regulation in performance and can conveniently meet the requirements on different release rates of growth factors or medicines. Meanwhile, the clinical injectable and in-situ forming operation requirements can be met, and the hydrogel has good application prospects in tissue repair and regeneration.

The invention provides a drug-loaded degradable blood vessel anastomat. The drug-loaded degradable blood vessel anastomat is characterized by comprising main components which are symmetrically arranged; each main component comprises a clamping part, a puncture part and a matching hole, and the puncture parts and the matching holes are symmetrically distributed in the clamping parts respectively; and the puncture parts of the adjacent main parts are connected with the corresponding matching holes in a matching manner. Through controllable degradation, the risk caused by retention of the vascular anastomat is reduced, the strength of the puncture parts can be guaranteed through a pointed iron core, the anastomosis effect is guaranteed, and meanwhile, an iron base body is degradable, the degradation component ferrous ions or iron ions are beneficial to formation of hemoglobin, and blood transportation is facilitated; and growth and differentiation of vascular cells can be promoted throughdrug loading, anastomosis of blood vessels at anastomotic positions is accelerated, generation of spots is reduced, and tissue damage is reduced to the maximum extent.

The invention discloses a high-density saline stimulation cross-linking type plugging agent and a preparation method and application thereof. The plugging agent consists of the following components inpercentage by mass: 10-90% of a main agent, 0.5-9% of a gelatinizing agent and the balance of clear water, wherein the main agent is one or more of dipotassium hydrogen phosphate, potassium phosphateand potassium pyrophosphate; and the gelatinizing agent is one or more of xanthan gum and kappa-carrageenan. The gelling time of the high-density saline stimulation crosslinking plugging agent at 90-160 DEG C is 0.5-12 hours (controllable), the final set strength can reach the visual inspection code D-H (controllable), and the density can be controlled to be 1.0-1.55 g / cm<3>. The high-density saline stimulation cross-linking type plugging agent is convenient to prepare on site and high in operability, and can be widely applied to construction operations such as well completion and temporary plugging and leakage prevention of well repair of high-temperature high-pressure multi-pressure strata oil and gas wells, perforation reservoir protection and water plugging.

The invention aims to provide a biodegradable composite film material of controllable degradation rate with good mechanical property, faster and more through degradation and no environmental harm, and a preparation method thereof. The material comprises the following components in parts by weight: 100 parts of matrix resin, 0-40 parts of other biodegradable polymers, 0.5-1.5 parts of heat stabilizer, 0.3-5 parts of nucleating agent, 1-5 parts of compatilizer, 2-15 parts of plasticizer and 0.3-5 parts of opener. The matrix resin is obtained by mixing poly lactic acid (PLA) and 3-hydroxybutyrate-3-hydroxy acid copolyester (PHBH) with each 20-80 parts by weight. The other biodegradable polymers are poly butylenes succinate (PBS), poly propylene carbonate (PPC), 3-hydroxybutyrate-3-hydroxyvalerate copolyester (PHBV) and terephthalic acid-butanediol-adipic acid copolyester (PBAT).

The invention discloses a preparation method of collagen sponge. The method comprises the following steps: carrying out enzymolysis on cattle heel tendon in protease aqueous solution at pH value of 1.0-5.0; centrifuging the enzymolysis liquid, collecting supernatant, and salting out collagen with saturated salt solution; dialyzing salted-out collagen; cross-linking the dialyzed collagen in a cross-linking agent aqueous solution; and freeze-drying cross-linked collagen gel, cross-linking the collagen in a cross-linking agent aqueous solution and freeze-drying to obtain the collagen sponge. The collagen sponge obtained by the preparation method of the collagen sponge disclosed by the invention has certain elastic and tensile toughness after being immersed in water, and has good biocompatibility and tissue repairing performance, and high protein content and is controllable in degradation.

The invention discloses a magnesium alloy material for oil and gas development, a preparation method and application thereof, which belong to the technical field of nonferrous metals. The composition content of the magnesium alloy material is: cerium-rich mixed rare earth: 0.5-25wt.%, Sn: 0-10wt.%; Fe: 0-10wt.%, Ti: 0-10wt.%; Ni: 0-10wt.% .%; Cu: 0~10wt.%; the balance is Mg. The tools made of the magnesium alloy material of the present invention can be used in oil wells, shale gas, and oil and gas wells for oil and gas production downhole operations, and the tools include soluble bridge plugs, soluble ball seats, fracturing balls, plugging balls, darts, etc. . The material can precisely control and predict the evolution of its mechanical properties and dissolution rate in the oil and gas well environment, establish an accurate prediction model, and directly select the most suitable composition and preparation and deformation methods for different shale oil and gas well environments, greatly shortening the delivery time cycle, ensure the safety and efficiency of oil and gas extraction, and reduce the risk and cost of production accidents.

The invention discloses an absorbable biological membrane as well as a preparation method and application thereof. The absorbable biological membrane is obtained by cross-linking collagen, cellulose derivatives and other polysaccharide substances by using a cross-linking agent. The absorbable biological membrane is obtained by utilizing a double-crosslinking technology, has the advantages of strong mechanical property, soft texture, toughness, low immunogenicity, controllable degradation and the like, has certain viscosity, can be effectively attached to a use part, is widely applied to the field of oral medicine such as periodontology, oral implantation and alveolar surgery, and has a wide application prospect. Moreover, the absorbable biological membrane can stabilize the bone grafting particles, so that the displacement of the bone grafting particles is avoided, the osteogenesis quality is improved, and the survival rate of the implant is greatly improved.

The invention relates to a preparation and application of a stitchable dura mater repairing material, and belongs to the field of a biomaterial and medical treatment and public health. The invention specifically discloses a preparation and application of a stitchable dura mater repairing material. The preparation comprises: extraction of target collagen, preparation of a compact layer, preparationof a porous layer, freeze-drying of dura mater, crosslinking and sterilization. The dura mater repairing material has a double-layer composite structure, and is good in mechanical property, is stitchable, and can effectively prevent bleeding of a cerebrospinal fluid. The material is high in purity and has a triple helical structure integratedly maintained in the compact layer. The material is good in biological activity and biological compatibility and controllable in degradation, and is a good substitute for cerebral dura mater and spinal dura mater.

The invention discloses a production process of tremella oligosaccharides, which relates to the field of sugar compound processing. Screening and purifying strains by selecting rotten tremella fungus, expanding and culturing the strains, and inoculating the strains into sterilized Fermentation is carried out in fresh white fungus, and finally the fermented white fungus is dried, gelatinized, acid-treated, high-temperature treated, crushed and sieved to obtain the required white fungus oligosaccharides. The beneficial effects of the present invention are: by selecting rotten white fungus to cultivate and purify bacterial strains, the production environment requirements and production costs for the existence of the bacteria are reduced, biological, chemical and physical methods are used to degrade the white fungus polysaccharides, and efficient and controllable degradation of the white fungus polysaccharides is realized, It reduces the difficulty of industrialization and is suitable for industrial application.

The invention relates to a medical device (10) comprising: a device body (12) preferably comprising a material susceptible to corrosion or bio-degradation and a shellac coating (14), wherein the device body (12) is at least partially covered by the shellac coating (14), wherein the shellac coating (14) has a thickness from 0.1 [mu]m to 20 [mu]m. Further, the invention relates to a method for manufacturing the medical device.