111 results about "Alginate hydrogel" patented technology

The invention discloses a chemical and ionic cross-linked alginate hydrogel flat membrane for filtration, which is designed and prepared aiming at the problems of poor stability, low mechanical strength, overlarge pores and the like of a pure ionic cross-linked hydrogel filtering membrane. According to the flat membrane, sodium alginate is used as a membrane forming substrate, a water-soluble compound is used as a pore-forming agent, and a chemical cross-linking agent and an ionic cross-linking agent are added, so that the sodium alginate is subjected to covalent bonding and ionic cross-linking to improve the stability of the membrane. The mechanical strength and the pore size of the membrane and the stability in an electrolyte solution are adjusted by changing the types and the proportions of the chemical cross-linking agent and the ionic cross-linking agent. The hydrogel flat membrane is prepared through a simple preparation process and is low in cost; no organic waste liquid is produced; the obtained hydrogel membrane can resist the pressure of 0.2-1 MPa and has a good application prospect in the separation field in which membrane pollution is easy to produce, such as oil-water separation, protein separation and biological sample filtration. The hydrogel flat membrane is directly discarded and can be fully degraded by microorganisms after being used, so that no environmental harm is caused.

The invention relates to a chitosan modified alginate hydrogel three-dimensional porous bracket with specific in-vitro degradability and a preparation method thereof. The method comprises the following steps: dissolving sodium alga acid serving as a raw material in phosphate buffer solution; performing amidation reaction of a carboxyl group in the sodium alga acid and an amino group in a cross-linking agent cystamine or dimethyl cystinate under the activation of water-soluble carbodiimide to form a chemically crosslinked hydrogel; performing freeze drying on the hydrogel to obtain a porous bracket material of the hydrogel; and performing surface modification on the porous bracket by using chitosan. In solution of a reducing agent such as cysteine with an appropriate concentration, a disulfide bond in a hydrogel cross-bridge is degraded through a disulfide bond-sulfydryl conversion reaction, so the porous bracket is decomposed and dissolved and disappears. Therefore, the porous bracket can be used as an in-vitro cell culture template material. The hydrogel porous bracket researched by the invention has the characteristics of simple preparation, rich raw material source, low cost and availability. Various physiochemical performances, mechanical strength, degradation rate and surface properties of the bracket material are controllable within a large range.

The invention relates to in-situ crosslinked alginate hydrogels with an active ingredient of disulfide bond disulfide bond alginate derivative. The preparation method thereof is as follows: the organic liquids of carbodiimide hydrochloride and N-hydroxysuccinimide eater are added into the alginate aqueous liquid of the alginate to activate the carboxyl of the alginate aqueous liquid; then the organic liquid of 4-aminothiolphenol is added under the conditions of keeping in dark place under 10 DEG C and nitrogen protection, so that the amino of the 4-aminothiolphenol and the carboxyl of the alginate aqueous liquid form an amido bond. The proportions of each matter adjusted and the pH value of muriatic acid is adjusted to 6.0, ethanol is deposited, frozen and dried to obtain sulfhydrylation alginates of different sulfydryl contents. The alginate aqueous liquid of the alginate oxidizes the sulfydryl thorugh the oxygen in the liquid under a room temperature to crosslink and form a disulfide bond, thus obtaining the crosslinked alginate hydrogels. The hydrogels prepared through the method has pH sensitivity and reduction responsiveness, and has potential application values in drug delivery field.

The present invention provides compositions including poly(alkenylamide)-polysaccharide hydrogels for treating a subterranean formation and methods of using the same. In various embodiments, the present invention provides a method of treating a subterranean formation, including obtaining or providing a composition including a poly(alkenylamide)-polysaccharide hydrogel. The method also includes placing the composition in a subterranean formation. In some embodiments, the poly(alkenylamide)-polysaccharide hydrogel is a polyacrylamide-alginate hydrogel.

The invention discloses a biomacromolecular hydrogel biological stent and a preparation method thereof and more specifically relates to an alginate hydrogel biological stent and a preparation method thereof. In the invention, the alginate hydrogel biological stent cross-linked by using a cross-linking agent is prepared in a water system by applying a layer-by-layer assembly technology, and pores are formed in the biological stent by using a method of generating CO2 foams in situ by using water-insoluble carbonate. The invention provides the simple and practical method, which is strong in controllability and low in cleaning cost, for preparing the biological stent.

The invention discloses a silk fibroin/alginate hydrogel material and a preparation method thereof. The preparation method comprise the following steps: (a) preparing a silk fibroin solution; (b) preparing an alginate solution; (c) mixing the silk fibroin solution and the alginate solution according to a certain ratio, evenly stirring, adjusting the pH value of the mixed solution, allowing the mixed solution to stand still to carry reactions at a certain temperature so as to a generate jelly-like substance; wherein the mass ratio of the silk fibroin to the alginate is 99:1-1:99. The prepared silk fibroin/alginate hydrogel material overcomes the shortage of bad mechanical property of silk fibroin hydrogel materials; furthermore, the silk fibroin/alginate hydrogel material has a similar structure, composition and functions as those of the cell epimatrix, and is an ideal tissue engineering material.

The present invention relates to a method for providing an embedded mammalian cell, comprising the steps of providing an alginate sulfate in aqueous solution; reacting the alginate sulfate to form a hydrogel in a gelation step, providing a precursor cell, and embedding the precursor cell in the sulfated alginate hydrogel in an embedding step, thus yielding an sulfated alginate hydrogel embedded cell. The invention further relates to sulfated alginate hydrogels, and cellular grafts comprising a mammalian cell embedded in sulfated alginate hydrogel.

The invention relates to an alginate-chitosan microcapsule modified via in situ covalent PEG grafting. The structure of the microcapsule is divided into two parts, i.e., a microcapsule membrane and an inner core, wherein the microcapsule membrane is a polyelectrolyte composite hydrogel membrane formed by chitosan and alginate, the surface of the membrane is modified via in situ covalent PEG grafting, and the inner core is an alginate liquid or alginate hydrogel environment containing living cells. Because of resistance to protein adsorption, the microcapsule is applied to living cell encapsulation and used as an immunoisolation carrier for cell transplantation.

Described herein are sacrificial templates generated from water soluble thermoplastic-divalent cation-composite materials, such as poly(vinyl alcohol)-calcium. Also described herein are methods for the use of such sacrificial templates in casting of precise internal space microarchitectures within hydrogels, such as microchannel networks within alginate hydrogels.

A novel chemically modified alginate hydrogel has been developed which combines an aromatic compound with a carbohydrate, where the aromatic compound is one or more amines combined with an alginate. The chemical structure of alginate is modified using different amines and different methods, including: (1) covalently bonding aminoethyl benzoic acid to the alginate backbone, and (2) oxidizing the vicinal diol in the alginate chain to an aldehyde before coupling to aminoethyl benzoic acid. Alternatively, the combined aromatic compound and carbohydrate can be a dopamine combined with the alginate. The chemically modified alginate and the methods used can be utilized to encapsulate a variety of bioactive substances for oral delivery in humans and animals, including, but not limited to: (i) drugs, medicines, enzymes, proteins, hormones, and vaccines, (ii) vitamins, minerals, micronutrients and/or other dietary supplements, (iii) probiotics and/or other microorganisms, (iv) cells, cell parts, and/or other biological materials, and/or (v) other bioactive substances.

The invention relates to alginate/hydroxyapatite super-long nanowire composite hydrogel. The alginate/hydroxyapatite super-long nanowire composite hydrogel comprises water-soluble alginate and hydroxyapatite super-long nanowires. According to the alginate/hydroxyapatite super-long nanowire composite hydrogel, the water-soluble alginate is combined with the hydroxyapatite super-long nanowires for the first time, and the alginate/hydroxyapatite super-long nanowire composite hydrogel with the alginate hydrogel as the base and the hydroxyapatite super-long nanowires as a reinforcing material is obtained finally. The prepared alginate/hydroxyapatite super-long nanowire composite hydrogel has the good mechanical performance and also has the good biocompatibility characteristic.

The invention relates to the technical field of printing and dyeing wastewater treatment. The invention discloses a preparation method and application of temperature-sensitive composite hydrogel by utilizing a synergistic effect of photocatalysis and temperature sensitivity. The temperature-sensitive composite hydrogel disclosed by the invention is prepared by the steps: introducing a temperature-sensitive copolymer and a photocatalyst into alginate hydrogel; the porosity of the hydrogel is adjustable in the temperature change process, a dye can be adsorbed and degraded under the illuminationcondition, and the adsorption capacity of the composite hydrogel to the dye is improved by virtue of the synergistic effect of a porous structure in the hydrogel caused by adding a catalyst and a loose structure formed by a temperature-sensitive copolymer at the temperature higher than the conversion temperature. And by virtue of the photocatalyst embedded in the hydrogel, the degradation of the adsorbed dye and the cyclic utilization of the composite hydrogel can be realized, and the composite hydrogel can be applied to the fields of printing and dyeing sewage treatment and the like.

Methods and devices for determining the concentration of a constituent in a body sample are provided. The body sample is introduced into a biosensor having a sample chamber and at least part of an electrode disposed therein. The biosensor also includes an alginate hydrogel substantially covering a portion of the sample chamber. The alginate hydrogel substantially includes an alginate polymer configured to reduce cellular migration.

The invention relates to a preparation method of a hydrogel dressing and in particular relates to a preparation method of an alginate hydrogel dressing, belonging to the technical field of preparation of a medical dressing. According to the preparation method provided by the invention, maleylated sodium alginate is synthesized, and processes of dissolving, ultraviolet illumination, freeze-drying, soaking and the like are carried out to form a double-crosslinking three-dimensional net structure with light crosslinking and ion crosslinking existing simultaneously, wherein the net structure of the ion crosslinking part is the alginate hydrogel dressing capable of being dissociated. The preparation method provided by the invention fully exerts the synergistic effects of chemical crosslinking and ion crosslinking, so that the dressing is endowed with good wet strength, toughness and elasticity. The alginate hydrogel dressing prepared by the preparation method has good biocompatibility and can not cause any damage to a wound when being applied to the wound, thereby being favorable for healing of the wound.

The invention relates to a preparation method of an alginate-hydrogel nanometer fiber scaffold. The preparation method comprises following steps: a polycaprolactone solution is prepared; a sodium alginate solution is prepared; a double-nozzle electrostatic spinning system is adopted for electrostatic spinning so as to obtain polycaprolactone-sodium alginate nanometer fiber film; the polycaprolactone-sodium alginate nanometer fiber film is immersed in a calcium chloride solution, is washed fully with an ethanol aqueous solution, is subjected to freeze drying, is immersed and washed with chloroform, is washed with ethanol and distilled water successively, and is subjected to freeze drying so as to obtain the alginate-hydrogel nanometer fiber scaffold. The alginate-hydrogel nanometer fiber scaffold possesses a stable three dimensional structure and excellent biocompatibility, can be used for 3D cell culture, and is capable of optimizing cell penetration depth.

The invention relates to an alginate embedded type hydrogel microsphere carrier having the interior containing a galactosyl chitosan molecule and a preparation method thereof. A galactosyl group is grafted onto a chitosan molecule by an amidation reaction, and hepatocytes are cultured in microcapsules jointly formed by chitosan and alginic acid. Experiments prove that the microcapsules jointly prepared by the galactosyl-grafted chitosan and alginic acid are used for culturing primary hepatocytes of rats, and the activity and function of the hepatocytes are well maintained.

The invention discloses an illumination-magnesium ion double-crosslinking alginate hydrogel and a preparation method thereof. The illumination-magnesium ion double-crosslinking alginate hydrogel can be prepared by preparing a precursor solution via an alginate solution with photo-crosslinking function, a photoinitiator and magnesium ions with bioactivity and carrying out of ionic reaction and ultraviolet illumination double-crosslinking reaction. According to the illumination-magnesium ion double-crosslinking alginate hydrogel and the preparation method thereof, the magnesium ions are imported into a bracket through an ion crosslinking manner, so that the biological characteristic of the bracket is simply and effectively improved; at the same time, a main framework is formed through photo-crosslinking, so that the stability of the bracket is ensured; and through ultraviolet initiation and the slow crosslinking characteristic of the magnesium ions, the favorable controllability of the bracket is ensured. The preparation method is simple and does not need to import other materials; and through controlling the concentration of the magnesium ions, the physical and chemical properties and the biological property of the hydrogel can be effectively adjusted and convenience is brought to the practical application.

The present invention relates to a galactosyl grafted-modified alginate hydrogel microsphere carrier preparation method. According to the present invention, the occupation on the hydroxyl site of alginic acid does not affect the gelation performance of the alginic acid, such that the embedding type hydrogel microsphere carrier with characteristics of good sphericity and good stability can be prepared from the galactosyl alginic acid being subjected to the grafting reaction, and can further be subjected to the film forming reaction with polycations to form the galactosyl alginate/polycation microcapsule.

The invention relates to the technical field of medical consumables, and discloses an alginate-hydrogel cold compress patch and a preparing method thereof. The alginate-hydrogel cold compress patch isprepared from, by weight, 10-100 parts of an alginate water solution, 0.1-5 parts of a cross-linking agent, 0.5-2 parts of a cool storage agent, 0.1-1 part of a thickening agent, 0.5-5 parts of a moisturizing agent, 0.5-1 part of an anti-freezing agent, 0.5-1 part of a blending agent and 0.01-0.5 part of cool and comfortable essential oil, and is prepared in the mode that the materials are subjected to a controllable cross-linking reaction. The technology for preparing the alginate-hydrogel cold compress patch is simple, the gel strength is suitable, the cold-compress curative effect durationtime is long, and the alginate-hydrogel cold compress patch is an ideal cold-compress patch product and suitable for large-scale application and production.

The invention belongs to the field of biological medical materials, and particularly relates to a collagen dressing containing polycaprolactone microspheres. The collagen dressing comprises water, andeach 100mL of the water contains 0.5-4g of collagen, 1-15g of hydroxyapatite, 0.5-3g of PCL drug-carrying microspheres, 2-5g of glucolactone and 3-8g of sodium alginate. A collagen/alginate hydrogelmaterial is prepared by combining collagen with an alginate solution through a simple composite gel path, and a medical material with high bioactivity and compatibility and capable of loading and slowly releasing drug can be obtained; by adding the PCL microspheres loaded with drug, stress scattering effect can be realized, and mechanical performance of the collagen dressing is improved; due to drug loading, slow release of the drug can be realized, the collagen dressing of 3D printing can be prevented from being polluted by bacteria, antibacterial and bactericidal effects can be realized, andwound repair and healing are facilitated.

The invention discloses a medical dressing for treating a large area wound and a manufacturing method thereof. The medical dressing is composed of from top to bottom: an isolation paper, a sodium alginate hydrogel, a non-woven fabric, a medical glue layer and a base cloth; or from top to bottom, an isolation paper, an alginate hydrogel, a medical glue layer and a base cloth. The sodium alginate hydrogel is a hydrogel mixed by 100 percent pure sodium alginate crystals and water. The alginate hydrogel is a hydrogel, which assumes a transparent gel shape formed by immersing a 100 percent pure calcium alginate non-woven fabric to a sodium alginate solution, automatically converts between a solid state and a liquid state based on changes of using state. The novelty of the invention lies in combining a material which promotes curing of the wound and a material which is secured to body surface. The medical dressing of the invention has the advantages of outside water resistance, extra-long adhering time, and simple operation and usage. The medical dressing of the invention faces towards the wound in humid environment, which promotes healing. The medical dressing can also reduce burning pain caused by the large area wound, prevent infection and wound adhesion, block bacteria from entering, and reduce times for changing medicine.

The invention relates to the technical field of tissue engineering articular cartilage repair, and specifically relates to a double cross-linked integrated seamless composite hydrogel scaffold for articular cartilage repair. The hydrogel scaffold successively includes a subchondral bone layer, a calcified interface layer and a cartilaginous layer from bottom to top; the subchondral bone layer is the hydrogel including bioceramic particles and alginate; the calcified interface layer is the polyelectrolyte electrostatic complex hydrogel including the alginate and polycation; the cartilaginous layer is the hydrogel including the alginate; and the alginate hydrogel in the subchondral bone layer, the calcified interface layer and the cartilaginous layer firstly forms ionic crosslinked hydrogeland then forms a double cross-linked integrated seamless structure through covalent crosslinking. The mechanical strength of the hydrogel scaffold is significantly superior to ionic crosslinked hydrogel scaffolds, so that interface bonding strength can be increased; and through the polyelectrolyte composite hydrogel membrane layer in the middle of the hydrogel scaffold, isolation effects on cartilage and subchondral bone microenvironment can be realized.