14 results about "Chitosan microspheres" patented technology

The invention belongs to the technical field of food or medicine, and particularly relates to a preparation method of nattokinase sustained-release microspheres, which comprises the following steps: mixing an emulsifier span-80 with liquid paraffin to obtain an oil phase; adding chitosan into an acetic acid solution to prepare a chitosan water solution as a water phase; dropwise adding the water phase into the oil phase to prepare W / O type emulsion, dropwise adding a cross-linking agent A into the emulsion to obtain chitosan microspheres, and taking a chitosan microsphere nattokinase solution and a cross-linking agent B to obtain nattokinase-chitosan core microspheres; mixing the nattokinase-chitosan core microsphere with a cortisol aptamer solution, and incubating to enable the aptamer to be combined on the surface of the nattokinase-chitosan core microsphere; and adding a casein-PEG copolymer solution and a cross-linking agent C into the microspheres to obtain the cortisol response type intelligent switch microspheres. The nattokinase release amount can be dynamically adjusted day and night, the circadian thrombus risk rhythm is matched, the anti-thrombus effect is remarkably improved, side effects are reduced, and the nattokinase can be widely applied to the fields of functional food and drugs.

The invention discloses a neural microelectrode for electrical stimulation combined with drug release and a preparation method thereof.The neural microelectrode comprises a first flexible substrate layer, a drug-loaded slow-release layer, a second flexible substrate layer, a conductive layer and an insulating covering layer, and the drug-loaded slow-release layer contains chitosan microspheres embedded with drugs; the medicament comprises nerve growth factors and / or anti-inflammatory drugs, a plurality of drug release holes are distributed in the insulating covering layer, an electrode contact is arranged at one end of the conducting layer, a lead connector is electrically arranged at the other end of the conducting layer, and openings for exposing the electrode contact and the lead connector are correspondingly formed in the two ends of the insulating covering layer respectively. According to the neural microelectrode provided by the invention, the drug-loaded slow-release layer is integrated in the neural microelectrode, so that a space for storing a drug does not need to be additionally processed on the membrane layer, and the drug does not need to be additionally loaded, so that the production and processing are relatively convenient and rapid; after the neural microelectrode is implanted into a corresponding tissue in a body, the drug-loaded sustained-release layer can be gradually degraded to slowly release a medicament for repairing nervous tissues or avoiding rejection reaction in a long-acting manner.

The application discloses a feed additive for removing microplastics, a preparation method and application. The composition consists of the following components in percentage by weight: modified chitosan microspheres 15-25%, nanoscale yeast cell wall derivatives 10-20%, fermentable dietary fiber complex 15-25%, glutamine 5-10%, complex probiotics and prebiotics 15-25%, and natural plant extract compound antioxidant 5-10%. The additive can be added to the feed at a weight ratio of 0.5-2.0% through a multi-target synergistic mechanism of 'adsorption-promoting excretion-repair-regulation', and can efficiently remove microplastics in aquatic products (the removal rate is up to 65% or more), improve intestinal health, enhance antioxidant function, reduce the residues of heavy metals and other complex pollutants, and significantly improve the edible safety and quality of aquatic products.

The invention discloses a feed additive for removing micro-plastics as well as a preparation method and application of the feed additive. The composition is prepared from the following components in percentage by weight: 15%-25% of modified chitosan microspheres, 10%-20% of a nanoscale yeast cell wall derivative, 15%-25% of a fermentable dietary fiber compound, 5%-10% of glutamine, 15%-25% of compound probiotics and prebiotics and 5%-10% of a natural plant extract compound antioxidant. The additive disclosed by the invention can be added into a feed according to a weight ratio of 0.5-2.0% through a multi-target synergistic mechanism of adsorption, discharge promotion, repair and regulation, so that micro-plastics in cultured aquatic products are efficiently removed (the removal rate is up to 65% or above), meanwhile, the intestinal health is improved, the antioxidant function is enhanced, the residues of composite pollutants such as heavy metals are reduced, and the feed quality is improved. The food safety and the quality of aquatic products are obviously improved.

The application belongs to the technical field of water treatment, and particularly relates to a phosphorus-containing modified magnetic chitosan microsphere, a preparation method thereof and application of the phosphorus-containing modified magnetic chitosan microsphere in treatment of chromium-containing underground water. Compared with the prior art, the phosphorus-containing modified magnetic chitosan microsphere provided by the application takes magnetic nanoparticles as a core, can be quickly separated from a reaction system by relying on external magnetic force of a system, and forms hydrogen bonds through hydroxyl groups of the magnetic nanoparticles and amino groups and hydroxyl groups of a chitosan molecular chain, so that stability and dispersibility of the magnetic nanoparticles are improved. Furthermore, a tetramethylammonium hydroxide solution is used as a crosslinking agent, so that a phosphorus-containing cationic group in the tetramethylammonium hydroxide is grafted on the chitosan molecule, thereby greatly enhancing adsorption performance of the chitosan on anionic heavy metal pollutants such as Cr(VI), and having long-term stability in remediation of Cr(VI)-contaminated underground water.

This invention discloses a continuous flow method for preparing chitosan hollow microspheres. The invention utilizes ultrasonic microreactor technology combined with emulsion crosslinking to successfully prepare chitosan hollow microspheres. The hollow chitosan microspheres provided by this invention are suitable for encapsulating various drugs, with a precisely tunable particle size within the range of 200 nm to 1.5 μm. They exhibit excellent biocompatibility and biodegradability, and a high drug loading capacity. The preparation process is a continuous synthesis process, resulting in highly uniform particle size and morphology of the product. The preparation process is safe, efficient, and easily scaled up.

This invention discloses a chitosan-based lidocaine formulation for intra-articular use and its preparation method. Belonging to the field of pharmaceutical formulation technology, the formulation is prepared from chitosan, carboxymethyl chitosan, lidocaine, chitosan-PNIPAM microspheres, sulfated trehalose, and excipients. The chitosan-PNIPAM used in this invention exhibits dual temperature and pH response. With temperature changes, PNIPAM possesses both hydrophobic contractile and hydrophilic swelling states, thereby controlling the lidocaine release rate. Simultaneously, when the pH decreases, chitosan repels PNIPAM, further disintegrating the microspheres to release the drug, thus achieving targeted analgesia. Sulfated trehalose, as a cartilage matrix synthesis promoter, can activate intracellular signaling pathways in chondrocytes, promoting the synthesis of type II collagen and proteoglycans. Simultaneously, the sulfate groups can form electrostatic complexes with the amino groups of chitosan, enhancing drug retention. The formulation of this invention can inhibit synovial cells, release cytokines, and synergistically with carboxymethyl chitosan, increase the inhibition rate of inflammatory factors by 40%-50%.

The hemostatic gauze for hemodialysis comprises a gauze body, and a plurality of restraint straps are arranged on the gauze body. A contact layer, a hemostasis layer, an isolation layer and a fixing layer are sequentially arranged on the gauze body from bottom to top; the contact layer is made of a hydrophilic biocompatible material; thrombin, chitosan microspheres and gelatin sponge are arranged in the hemostatic layer; the isolating layer is made of a polytetrafluoroethylene film, and the fixing layer is made of elastic medical non-woven fabric. According to the multi-layer structural design that the gauze body is sequentially provided with the contact layer, the hemostasis layer, the isolation layer and the fixing layer from bottom to top, and all the layers are clear in function and cooperate with one another; the contact layer is in direct contact with the wound and is responsible for primary blood coagulation promotion and adhesion prevention; the hemostatic layer can stop bleeding efficiently; the isolating layer plays a dual role in blocking outside bacteria and preventing adhesion; the fixing layer ensures that the whole gauze is stably fixed at the wound part; due to the layered structural design, the hemostatic gauze can effectively meet various requirements for hemostasis and follow-up nursing of a hemodialysis puncture part.

The invention provides propranolol temperature-sensitive hydrogel as well as a preparation method and application thereof, and belongs to the technical field of medicines. The propranolol temperature-sensitive hydrogel disclosed by the invention is prepared from chitosan-beta-sodium glycerophosphate hydrogel and nano microspheres loaded on the chitosan-beta-sodium glycerophosphate hydrogel, wherein the chitosan-beta-sodium glycerophosphate hydrogel is a chitosan-beta-sodium glycerophosphate hydrogel; the nano microspheres are chitosan microspheres which are used for encapsulating propranolol; the mass of the nano microspheres is 1%-20% of the mass of the chitosan-beta-sodium glycerophosphate hydrogel. The propranolol temperature-sensitive hydrogel provided by the invention is a dual slow-release temperature-sensitive hydrogel system, not only has remarkable controlled release performance, can release drugs more continuously and stably, but also has good drug loading property and stable rheological property.

The invention relates to water-soluble CBCS microspheres and preparation and application thereof. Chitosan is dissolved in a solvent to dissolve and swell, and then phthalic anhydride is added for reaction to obtain a reaction solution. The reaction solution is poured into water to cool, the pH value is adjusted to alkaline, and the filtrate is filtered and dialyzed. The filtrate is freeze-dried to obtain flocculent light yellow solid CBCS: N-(2-carboxybenzoyl)-chitosan. The CBCS solution is dripped into an oil phase and an emulsifier for emulsification, and then an aldehyde cross-linking agent is added to cross-link and solidify amino groups and aldehyde groups of the CBCS to generate shiff base bonds to obtain the CBCS microspheres. The CBCS microspheres can adsorb antibiotics in water in accordance with the Langmuir model, and the adsorption process conforms to pseudo-secondary adsorption kinetics. The water solubility and yield of chitosan can be increased, the chitosan microspheres are improved in terms of reusability, and the scope of application can be further broadened. The CBCS microspheres can efficiently, economically, and environmentally friendly treat antibiotic pollution in wastewater.

The application discloses an antibacterial medical packaging material and a preparation method thereof, and relates to the packaging material field. When the antibacterial medical packaging material is prepared, chitosan and N-methylcarbazole-3,6-dialdehyde are reacted to obtain chitosan microspheres; then the chitosan microspheres are sequentially reacted with 2-mercapto-S-thiobenzoyl acetic acid and allyl trimethyl ammonium chloride to obtain modified chitosan microspheres; polylactic acid is reacted with 2-aminoethyl hypophosphorous acid to obtain modified polylactic acid; and the modified chitosan microspheres and the modified polylactic acid are uniformly mixed and then extruded into a film to obtain the antibacterial medical packaging material. The antibacterial medical packaging material prepared by the application has excellent flame retardance, antibacterial property and mechanical property.

The application discloses an intravenous injection immunotargeting microsphere and a preparation method and application thereof, and relates to the field of lung tissue engineering.The method steps of the application comprise the following steps: preparing a drug-loaded chitosan solution; preparing the drug-loaded chitosan microsphere by using a water-in-oil emulsion method; grinding the drug-loaded microsphere in a mortar; then, the drug-loaded chitosan microsphere is soaked in a dopamine solution to react for a period of time to construct a dopamine active coating; finally, the abundant amino and hydroxyl functional groups of the chitosan microsphere are combined with an immunotargeting factor iNOS inhibitor through electrostatic interaction.The intravenous injection immunotargeting microsphere prepared in the application has good biocompatibility and size stability, can specifically recognize target cells and realize precise drug delivery, effectively improves the treatment efficiency of acute lung injury, and has good clinical application potential.

The invention provides cod liver oil pure chitosan microspheres as well as a preparation method and application thereof, and belongs to the technical field of chitosan microspheres. The method comprises the following steps: uniformly stirring cod liver oil and a chitosan solution according to a volume ratio of 1: (2-6) to obtain an emulsion m1; extruding the emulsion m1 into a sodium dodecyl sulfate solution to obtain cod liver oil chitosan microspheres ms2; drying the cod-liver oil chitosan microspheres ms2, and putting the cod-liver oil chitosan microspheres ms2 into a sodium dodecyl sulfate solution for standing to obtain cod-liver oil chitosan microspheres ms3; immersing the cod-liver oil chitosan microspheres ms3 into a sodium hydroxide solution, and then washing the cod-liver oil chitosan microspheres ms3 to be neutral to obtain cod-liver oil chitosan microspheres ms4. Through a self-assembly technology at a mild temperature, a cross-linking agent does not need to be used, the preparation process is simple, and the obtained cod-liver oil pure chitosan microspheres are high in biological safety, good in antibacterial activity and high in embedding rate. The invention also provides application of the cod-liver oil pure chitosan microspheres in preparation of foods and medicines, and the cod-liver oil pure chitosan microspheres have a good application prospect.

The present application relates to a kind of active wound dressings based on bacterial cellulose and chitosan microspheres encapsulating drugs and its preparation method, the chitosan microspheres utilize bacterial cellulose nanometer network as dispersed phase, let chitosan be dispersed in bacterial cellulose matrix into ball by ionic crosslinking method, and drug is encapsulated in ball, microsphere is attached on the nanometer fiber inside bacterial cellulose film or network inside pore.The active wound dressings of the present application has broad-spectrum antibacterial property and biological safety;Method is simple and efficient and avoid the use of toxic crosslinking agent, can make chitosan microspheres evenly distributed in film.When the encapsulated drug is berberine, it has the potential to treat diabetic foot.