226 results about "Chitosan microsphere" patented technology

The invention relates to an acid-resistant magnetic chitosan microsphere adsorbent as well as a preparation method and the application thereof, and in particular relates to acid-resistant magnetic chitosan microspheres which have the excellent absorption performance and recycling performance for acid waste water containing hexavalent chromium, a preparation method of the acid-resistant magnetic chitosan microspheres and the application of the acid-resistant magnetic chitosan microspheres. The preparation method of the acid-resistant magnetic chitosan microspheres comprises the following steps: (1) preparing Fe3O4 nano-particles modified by citric acid by using a coprecipitation method; (2) preparing single-coated magnetic SiO2 nano-particles by using a sodium silicate hydrolysis method or a sol-gel method; and (3) preparing the chitosan microspheres coated with magnetic SiO2 by taking chitosan powder as a raw material by adopting an emulsion crosslinking method. Furthermore, in order to further improve the adsorbing capacity of the microspheres, in the method, dendritic polyethylene imine is taken as a functional group for modifying the adsorbent, so that the modified chitosan microspheres can be obtained. The magnetic chitosan microspheres prepared by adopting the method not only have the excellent acid resistance, but also have the good absorption performance on Cr (VI) ions.

The invention discloses injectable compound bone cement and a preparation method thereof. The invention further discloses a kit for preparing the injectable compound bone cement. The kit comprises solid powder and a curing liquid, wherein the solid powder comprises calcium phosphate bone cement powder and chitosan microspheres; and the curing liquid contains glycerophosphate. The injectable compound bone cement is prepared by uniformly mixing the solid power with the curing liquid, has superior scattering resistance, superior injection performance, rapid self-curing performance, high compressive strength and high biocompatibility, and can be used for preparing a biomedical material applied to bone defect reconstruction, bone fracture treatment and bone repair.

The invention relates to a method for detecting ten types of organophosphorus pesticides by using magnetic separation-gas chromatography. The method is used for quickly detecting ten types of organophosphorus pesticides (dipterex, methamidophos, acephate, omethoate, moncrotophos, dimethoate, phosphamidon, parathion-methyl, malathion and chlorpyrifos) based on combination of solid-phase extraction, magnetic separation and the gas chromatography. The method comprises the following steps: preparing a magnetic solid-phase extraction agent, establishing a combination system of the magnetic separation and the gas chromatography, and detecting the organophosphorus pesticides in objects to be detected. A method capable of quickly separating and detecting ten types of organophosphorus pesticides at high sensitivity simultaneously is established by taking prepared magnetic chitosan microspheres with high absorption performance on the ten types of organophosphorus pesticides such as dipterex and the like as adsorption functional materials and using combination of the solid-phase extraction, magnetic separation and the gas chromatography. The method is simple in experimental operation, high in detection sensitivity, low in cost and applicable to detection of residues of ten types of organophosphorus pesticides such as trace dipterex and the like in all products.

The invention relates to a graphene oxide and chitosan microsphere and a preparation method thereof. According to the technical scheme, chitosan is dissolved in a graphene oxide dispersing agent obtained through ultrasonic dispersion, and graphene oxide and chitosan mixed liquor is obtained; liquid paraffin and span-80 are sequentially added to the graphene oxide and chitosan mixed liquor, and stirring is conducted for 2-4 h; formaldehyde is added, and stirring is conducted continuously for 1-2 h; a NaOH solution and an absolute ethyl alcohol are added, stirring is conducted for 2-4 h, washing and filtering are conducted, and a graphene oxide and chitosan pre-crosslinked microsphere is obtained; on the condition that the temperature ranges from 65 DEG C to 70 DEG C, the graphene oxide and chitosan pre-crosslinked microsphere is added to an epoxy chloropropane solution, stirring is conducted for 3-5 h, washing, filtering and vacuum drying are conducted, and the graphene oxide and chitosan microsphere is obtained. According to the graphene oxide and chitosan microsphere and the preparation method thereof, the preparation technology is simple; the prepared product has the advantages of being large in particle size, good in mechanical property, prone to sedimentation, prone to be separated from water, high in chelating capacity to heavy metal ions and good in adsorption property to the heavy metal ions.

The invention discloses an injectable biological active factor composition and a preparation method thereof. The biological active factor composition comprises one or more than one cell growth factor with biological activity, an isotonic chitosan solution and chitosan microspheres suspending in the solution, and temperature-dependent gelatinization is carried out to form hydrogel. The preparation method of the biological active factor composition comprises the following steps of: preparing the isotonic chitosan solution, and adding biological active factors and chitosan microspheres to form the biological active factor composition. The biological active factor composition can be applied to the defective parts of bones or cartilages in an injection mode, the hydrogel is formed in situ at the physiological pH value and temperature, and biological active factors are slowly released.

The invention discloses a compound growth factor of blood platelet sources as well as a preparation method and application of the compound growth factor. According to the compound growth factor as well as the preparation method and the application of the compound growth factor, platelet-rich plasma as the raw material is firstly subjected to virus inactivation through an S/D (Solvent/Detergent) method to remove such reagents as organic solvents and eradicators in the platelet-rich plasma and then activated by adding calcium or/and thrombin, supernatant fluid after activation is extracted to obtain the compound growth factor fitting for the natural proportion of the human body; and the problems that single recombinant growth factors in clinic are high in price, and difficult to purify, is involved into gene recombination biological safety and on the like are overcome. The invention further discloses a compound growth factor gel obtained based on the compound growth factor by adding chitosan microspheres carriers, which can slowly release growth factors during use. The compound growth factor has remarkable treatment effects for acute wounds, burns, cosmetic treatment, and chronic hard-healing wounds, is convenient to use, and has high safety.

The invention relates to a Brevendimonas vesicularis strain and application thereof in preparing an immobilized microbial adsorbent. The application method comprises the following steps: carrying out co-culture on a Brevendimonas vesicularis S3 solution and chitosan so that the Brevendimonas vesicularis S3 grows and is adsorbed to the chitosan surface to form an immobilized Brevendimonas vesicularis S3 chitosan composite material, carrying out vacuum filtration, and carrying out low-temperature vacuum drying; adding the obtained microbial composite material into a sodium-alginate-containing water solution, uniformly stirring and mixing, dropwisely adding a calcium chloride solution so that the microbial chitosan composite material is embedded to form sodium alginate microbial chitosan microspheres, washing with water, and airing to obtain the immobilized bacterium microspheres. The Brevendimonas vesicularis S3 is collected by China General Microbiological Culture Collection Center, and the collection number is CGMCC No.11072. The immobilized bacterium microspheres can be used for treating heavy-metal-polluted industrial wastewater, have the advantages of low cost and favorable effect, and are convenient and easy to recycle.

The invention discloses a chitosan microsphere loaded nano silver antibacterial polypropylene material, a composite antibacterial agent and a preparation method thereof, belonging to the field of polymer material modification. The preparation method of the chitosan microsphere loaded nano silver antibacterial polypropylene material comprises the following steps of: (1) synthesizing a chitosan microsphere/nano silver composite antibacterial agent; and (2) blending the composite antibacterial agent and a polypropylene resin matrix to prepare the antibacterial polypropylene material. The composite antibacterial agent takes chitosan microspheres as carriers, and nano silver is loaded on the chitosan microspheres; and the composite antibacterial agent has the advantages of small dosage, environmental protection, low price, excellent and lasting antibacterial performance and the like, and the antibacterial polypropylene material prepared from the composite antibacterial agent not only has strong antibacterial performance, but also has improved mechanical performance. In addition, the composite antibacterial agent and antibacterial polypropylene material have simple preparation process and easy operation, are suitable for industrial application, and have high economic and social values.

The invention discloses a preparation method of an amino-terminated hyper-branched polymer grafted chitosan microsphere adsorbent (the simple formula is represented by figure I), and belongs to the field of preparation processes of adsorbing materials. According to the present invention, a hyper-branched polymer is cross-linked in a chitosan structure through succinic anhydride by using the rich nitrogen-containing groups (primary amino group, amide group and secondary amino group) in the hyper-branched polymer based on the highly-reactive amino group in the molecular structure of chitosan toprepare the amino-terminated hyper-branched polymer grafted chitosan solid-phase adsorbing material having a specific structure, wherein the adsorbing material is used for formaldehyde adsorption; a large amount of the nitrogen-containing groups are introduced on the chitosan so as to increase the content of the active groups, such that the formaldehyde adsorption capacity can be significantly improved; and by using the ionic liquid as the reaction medium for cross-linking the hyper-branched polymer and the chitosan, the reaction rate can be significantly increased, the cross-linking proportion can be increased, and the ionic liquid can be recycled so as to achieve the environmental protection.

The invention discloses a preparation method of a cadmium removal agent of a thiolated chitosan microsphere. The method comprises the steps of imprinting chitosan with a cadmium ion, then carrying out cross-linking forming with tripolyphosphate, eluting the cadmium ion with hydrochloric acid to prepare a chitosan microsphere, and modifying with carbon disulfide under an alkaline condition to prepare a finished product. A material prepared by the method has good absorption and chelation effects on the cadmium ion, is used for cadmium wastewater treatment, and can allow wastewater to reach the standard for discharge and recover the cadmium ion in the water.

The invention belongs to the field of polymer materials, and relates to a chitosan microsphere preparation method, firstly, chitosan solutions with different volatile properties are prepared by adjustment of the ratio of solvents, the chitosan solutions are s dispersed into tiny droplets by use of electrostatic spray method by electrostatic force; secondly, the tiny droplets are formed into microsphere morphology in the air through the process of solvent evaporation, shrinkage and the like, and finally are received by an emulsion crosslinking agent prepared from liquid paraffin, petroleum ether, Twain-80 and glutaraldehyde. After the electrostatic spray, chitosan microspheres are obtained by centrifugal separation, washing with ethanol and other steps. According to the method, the chitosan microspheres are obtained from a natural polymer material by electrostatic spray emulsification crosslinking method, the method is low in requirement to equipment, a collecting device and post-processing process are simple, cost is low, the emulsification and cross-linking agent can be used repeatedly, and the obtained chitosan microspheres are small in particle size and non-sticky.

The invention relates to a new thymosin chitosan microsphere type oral medicinal preparation and a preparation method thereof. The technical scheme is that the new thymosin chitosan microsphere type oil medicinal preparation is obtained by utilizing chitosan to microencapsulating thymosin. The preparation method comprises the following steps of: dissolving the chitosan in an acetic acid solution to form a chitosan and acetic acid solution; adding inorganic salt and the thymosin in the chitosan and acetic acid solution and stirring to fully dissolve the inorganic salt and the thymosin to be used as a water phase; using liquid paraffin containing an emulsifier as an oil phase; dropwise adding the water phase into the oil phase and stirring; dropwise adding a cross-linking agent, stirring, and then carrying out cross-linking solidification; centrifuging, washing and drying the obtained product. The thymosin chitosan microsphere type oil medicinal preparation realizes the slow medicament release in bodies with thymosin so as to provide foundation for the treatment of the clinical thymosin and auxiliary medicament administration.

The invention discloses a preparation method of a pH sensitiveness raphanin chitosan microsphere. The preparation method comprises the following steps: 1) dissolving chitosan powder into an acetic acid solution; 2) taking a raphanin water solution and adding into the acetic acid solution; and 3) dropping a sodium tripolyphosphate solution into the mixture liquid obtained in the step 2) so as to obtain the raphanin-chitosan microsphere. The preparation method of the pH sensitiveness raphanin chitosan microsphere is reasonable in design, and the microsphere is prepared by using an ionic cross-linking method in a mode that the chitosan is taken as a carrier and the sodium tripolyphosphate is taken as a cross-linking agent, the experiment is simple and mild, and no organic solvents are used, so that the method is safe and environmental-friendly, a drug carrying microsphere solution of which the average particle size is 500 nm is successfully prepared, and moreover the prepared microsphere solution is good in stability and has no great change in particle size after being placed for a long time; under the acidic condition, the raphanin can be released more easily, and the higher the pH value is, the longer the releasing time is, and therefore the microsphere is an ideal slow release formulation of the raphanin.

The invention discloses a method for preparing functionalized graphene. The method includes the following steps that oxidized graphene and magnetic chitosan microspheres are respectively prepared; the oxidized graphene is dispersed in a deionized water solution to obtain an oxidized graphene solution, and the magnetic chitosan microspheres are soaked into the oxidized graphene solution and subjected to standing to obtain the functionalized graphene. The method for preparing the functionalized graphene has the advantages that chitosan which is nontoxic, low in price, easy to obtain and wide in source and graphite powder are used as raw materials, the oxidized graphene and the magnetic chitosan microspheres are self-prepared in a lab and are combined through an electrostatic interaction to prepare the functionalized graphene material, and the adsorption performance of the functionalized graphene material to heavy metal ions in water is studied. The functionalized graphene is simple in preparation process and wide in source of raw materials, fully utilizes repairing performance of the oxidized graphene to polluted water, and is also combined with separability of the magnetic chitosan microspheres.

The invention relates to a method for preparing a novel preparation of pesticide, and particularly relates to an abamectin B2 chitosan microsphere, as well as a preparation method and application thereof. The preparation comprises abamectin B2 and chitosan, wherein the mass percentage content of abamectin B2 is 5.0-20.0 percent. The preparation method comprises the steps of dispersing an abamectin B2 soluble solution in a chitosan aqueous solution in diluted acid, performing spray-drying through a spray drier, and collecting dried powder to obtain a chitosan microsphere product. The abamectin B2 chitosan microsphere can be used for preventing and controlling crop nematode. According to the preparation method, an emulsification-spray drying method is adopted to prepare the abamectin B2 chitosan microsphere, high-molecular polymer carrier is dissolved in an aqueous phase, and the effective ingredient is dissolved in an oil phase, so that the oil-phase medium is greatly reduced, and usage of harmful organic solvent is reduced; and the preparation method is simple and convenient, has mild condition, does not need harmful organic solvent, has good environment compatibility, and is especially applicable to industrial production.

The invention relates to chitosan microspheres. The microspheres are solid spheres which have smooth surface and uniform granularity and are formed by crosslinking of chitosan and a crosslinking agent, wherein the grain diameter of each microsphere is 50-1200 mu m, preferably 50-600mu m, and further preferably 150-300mu m; and the grain diameter difference is not more than 20 percent, and preferably not more than 10 percent. The microspheres provided by the invention have the characteristics of small grain diameters and high uniformity, and are capable of improving the safety effectiveness of embolism in interventional therapy, reinforcing the clinical operability, reducing the clinical safety accident rate and reducing the production cost.

The invention provides a preparation method and application of a chitosan-microsphere immunoaffinity adsorbent and belongs to the technical fields of development and application of natural polysaccharide and preparation of functional materials. The preparation method comprises the following steps of: preparing chitosan solution, weighing and taking liquid paraffin containing an emulsifying agent span 80, adding the liquid paraffin into the chitosan solution, stirring, and emulsifying to obtain mixed liquid; adding a crosslinking agent to carry out stirring crosslinking, and carrying out Soxhlet extraction, alcohol rinsing, washing, reduction and rewashing to obtain chitosan microspheres; stirring and coupling the chitosan microspheres and antibiotics, washing with distilled water and PBS (Phosphatic Buffer Solution), and finally obtaining the chitosan-microsphere immunoaffinity adsorbent. The chitosan-microsphere immunoaffinity adsorbent prepared by the invention is homogeneous in particle size of the microspheres, has better pH stability and can be used for purifying, separating and measuring the antibiotics in a food sample.

The invention provides a preparation method of a tourmaline/magnetic chitosan microsphere treatment agent which is prepared by dissolving and uniformly mixing mixed powder of tourmaline and magnetic chitosan microspheres in sodium alginate and polyvinyl alcohol, and solidifying and balling. The magnetic chitosan microsphere is prepared by using superparamagnetic ferroferric oxide, 1 to 10 weight percent of chitosan acetic acid liquid, liquid paraffin, Span-80 and glutaraldehyde as reaction materials through an emulsion crosslinking method, wherein the mass ratio of the superparamagnetic ferroferric oxide to the chitosan acetic acid liquid is 1:(1-10), the volume ratio of the liquid paraffin to the Span-80 is (10-100):1, the volume ratio of the chitosan acetic acid liquid of superparamagnetic ferroferric oxide to mixed liquid of paraffin-Span-80 is 1:(1-10), and the volume ratio of the mixed liquid of superparaferroferric oxide, paraffin and Span-80 to glutaraldehyde is (5-50):1. According to the water treating agent, the removal rate of volatile phenol in water is between 80 and 90 percent, the removal rate of chromium in water is 93 percent; and the magnetic chitosan microsphere treating agent has the advantages of large adsorption capacity, high purification efficiency, low cost, regeneration, no toxicity, no pollution to environment and the like.

The invention discloses a preparation method of a collagen coating embedded with chitosan microspheres on a medical metal implant surface. The mineralized collagen coating embedded with the chitosan microspheres is formed on a substrate by adopting an electrochemical deposition method and adjusting parameters such as a pH (potential of hydrogen) value and on-load voltage of an electrolytic solution. The method is simple in technology; the prepared coating is embedded with the chitosan microspheres; and as the chitosan microspheres has an effect of effective controlled release of biological factors or drugs such as antibiotics, the coating has high biological responsiveness, a good drug sustained release function and a wide application prospect in the field of hard-bone tissue repair.

The invention belongs to the field of veterinary preparation, and relates to a veterinary preparation namely lysozyme-loaded chitosan microspheres and a preparation method thereof. The chitosan with a molecular weight of 5 to 50 kDa is crosslinked with an electronegative crosslinking agent through the electrostatic action so as to form microspheres, and the lysozyme is encapsulated in the microspheres. The ion-crosslinking method and the freeze-drying method are co-used to prepare the veterinary preparation, the reaction conditions are mild, the technology process is controllable, the industrialization development becomes easier, and thus the preparation method is practical. The lysozyme and chitosan can generate a synergetic effect, the chitosan with a molecular weight of 5-50 kDa can penetrate the outer membrane of G- cells, and thus the lysozyme can be transferred to the inner wall layer of G- cells to hydrolyze the peptidoglycan structure, so that the inhibiting performance of lysozyme on Gram-negative bacteria (G-) is effectively strengthened, and the preparation can partially replace the broad-spectrum antibacterial effect of antibiotics.

The invention discloses a bacterial cellulose composite membrane for medical dressings and a preparation method thereof. The composite membrane is prepared from a pretreated membrane and a silver nitrate solution, the prepared composite membrane is soaked in the silver nitrate solution, ultraviolet reduction is conducted through irradiation of an ultraviolet lamp, nano-silver particles are generated, and the antibacterial performance of the composite membrane is further improved. The pretreated membrane is prepared from the following raw materials in parts by weight: 10 to 15 parts of modifiedchitosan microspheres, 15 to 28 parts of modified bacterial cellulose, 10 to 12 parts of acrylamide, 6 to 12 parts of N, N-methylene bisacrylamide, 2 to 5 parts of ammonium persulfate, 7 to 10 partsof sodium alginate, 4 to 6 parts of calcium chloride and 6 to 9 parts of collagen. The bacterial cellulose membrane is reasonable in component design and simple in technological operation, preparationof the bacterial cellulose membrane is effectively achieved, the bacterial cellulose membrane has excellent antibacterial performance and excellent mechanical performance, and the bacterial cellulosemembrane can be applied to the fields of medical treatment, biology and the like and is wide in application prospect.

The invention discloses a microsphere material prepared from a chitosan solution with the pH value of 6-8 and a preparation method of the microsphere material. The preparation method comprises the following steps: (1) preparing a dispersion liquid; (2) adding chitosan into the dispersion liquid, controlling the temperature to range from a freezing point to 35 DEG C, introducing carbon dioxide intothe solution, stirring to dissolve the chitosan, stopping introduction of the carbon dioxide after the chitosan is completely dissolved, and defoaming to obtain a transparent chitosan solution with the pH value of 6-8; and (3) enabling the chitosan aqueous solution and an oil phase to form chitosan emulsion drops through a membrane emulsifier or microfluidic equipment or a conventional stirring device, and curing the emulsion drops through a coagulator or a chemical cross-linking agent to form the chitosan microspheres. The microsphere material and the method have the beneficial effects that:the method for preparing the chitosan microspheres is carried out in an environment with the pH value of 6-8, and degradation of a chitosan molecular chain can be effectively weakened; and the process of preparing the chitosan microspheres is environment-friendly, so that the production efficiency is improved, and the production cost is reduced.

The invention relates to a method for preparation of sucrose-6-acetate from fructosyl transferase. The method includes the steps of: S1. preparation of fructosyl transferase; S2. preparation of immobilized fructosyl transferase; S3. catalytic synthesis of sucrose-6-acetate with fructosyl transferase in a nonaqueous phase reaction system; and S4. separation and purification of sucrose-6-acetate. The invention has the technical characteristics that: the invention establishes a fructosyl transferase separation and purification method; the invention establishes a fructosyl transferase immobilization method, magnetic chitosan microspheres are adopted as the carrier, and genipin is taken as the cross-linking agent; the invention establishes a method for catalytic synthesis of sucrose-6-acetate with immobilized fructosyl transferase, the ionic liquid [Dmin][PF6] and tert-butyl alcohol mixed solvent is taken as the reaction medium, and sucrose and glucose-6-acetate are adopted as the substrate to carry out catalytic synthesis of sucrose-6-acetate, the output and the yield respective reach 57.2g/L and 86.2%; and the invention establishes a separation and purification method for the product sucrose-6-acetate, the purity reaches 99.3%, and the recovery rate reaches 96.2%.

The invention relates to a polyethyleneimine-chitosan adsorbent one-step synthesis method. The method comprises the following steps: firstly, chitosan, polyethyleneimine and glacial acetic acid are prepared into an inner phase solution, and liquid paraffin and petroleum ether are prepared into an outer phase solution; secondly, the inner phase solution and the outer phase solution obtained the first step are injected into a focal flow-type micro-fluidic chip, a series of chitosan liquid drops are prepared; thirdly, when the chitosan liquid drops in the second step are generated stably, the chitosan liquid drops are introduced into a crosslinking solidification liquid, and chitosan microspheres are prepared; fourthly, the chitosan microspheres obtained in the third step are cleaned for many times in an ethanol solution, an acetone solution and deionized water in order; fifthly, the chitosan microspheres obtained in the fourth step are subjected to freeze-drying, and a polyethyleneimine-chitosan adsorbent is obtained.