1839 results about "Immobilized enzyme" patented technology

A composition of enzyme, polymer, and crosslinker forms a network of covalently bound macromolecules. The covalently immobilized enzyme preparation has enzymatic activity, and retains stable activity when dried and stored at ambient conditions. Methods for preparing an immobilized enzyme and methods for using the enzyme are disclosed.

The invention relates to a functional-material-based glucose biosensor. A working electrode of the glucose biosensor is made from a graphene nanomaterial, the glucose biosensor is formed by using the working electrode made from the graphene nanomaterial in the assembling of the glucose biosensor, belongs to a quantitative test technology and shows excellent linearity and resolution, and the detection sensitivity, the detection range and the detection speed are increased; and particularly in the concentration range of human blood glucose, the amplitude of a response current can be increased by 50%, and the resolution can be increased by over twice. The functional-material-based glucose biosensor and a preparation method thereof have the advantages that: immobilized enzyme of a nano-functional membrane prepared from the graphene nanomaterial can be continuously analyzed for over 1,000 times, so that the cost for measurement is low, the accuracy of analysis is higher than that of other methods, the relative error reaches about 1%, the response time is shortened to 20 seconds, the service life is also greatly prolonged, the precise timing measurement of the concentration of glucose can be achieved; and the functional-material-based glucose biosensor has the characteristics of high specificity, short-time performance, low-cost analysis, no special requirements on analyzing substances, safety and simplicity and convenience in operation, and convenience for on-site measurement and the like and can be applied to the daily measurement of blood glucose of diabetes patients.

The invention provides a polymeric hydrogel grafted on fibers by calcium ion crosslinking and a preparation method thereof. The polymeric hydrogel comprises the following components in percentage by mass: 3-8% of sodium polyacrylate grafted fiber, 0.96-4% of sodium alginate, 0-2% of water-solubility polymeric additive, 0.96-8% of calcium chloride and 75-95% of deionized water. The preparation method comprises the following steps: grafting polyacrylic acid on fibers by ultraviolet radiation; neutralizing with sodium hydroxide to obtain sodium polyacrylate-grafted fibers; soaking sodium polyacrylate-grafted fibers in an aqueous sodium alginate solution; taking out and scraping off the superabundant adherent viscous solution; and crosslinking in an aqueous calcium chloride solution to obtain the calcium alginate hydrogel grafted on the fibers. The preparation method is simple to operate, and the prepared polymeric hydrogel grafted on fibers has application prospects in the fields of adsorption separation, drug control and release, immobilized enzyme, tissue engineering and the like.

This invention discloses one static fabric processed fixed enzyme electrode and its method, which belongs to fixed enzyme electrode technique, wherein, the said enzyme electrode is composed of electrode base, reacting layer composed of polymer nanometer fiber film and oxidation and deoxidizing enzyme or the reacting layer is composed of polymer nanometer fiber film and oxidation and deoxidizing enzyme and metal particles with 5 to 100 nanometer electric activity or the reacting layer is composed of polymer nanometer fiber film and film oxidation and deoxidizing enzyme and electro medium.

The invention discloses a preparation method and an application of a nano material monolithic column immobilized enzyme biological micro-reactor. The preparation method comprises the following steps of firstly, preparing a porous organic polymer monolithic column by using a mixed solution of a functional monomer, a crosslinking agent, a pore forming agent and an initiating agent through in-situ thermal-initiated or light-initiated polymerization in the column, and then bonding a nano material after functional modification to obtain a nano material monolithic column; and secondly, realizing immobilization of the enzyme on the monolithic column by using the nano material as an intermediate ligand to obtain the nano material monolithic column immobilized enzyme biological micro-reactor. The biological micro-reactor is successfully applied to proteomic analysis, medicament chiral resolution and catalyzed ester exchange reactions. The biological micro-reactor disclosed by the invention has the following advantages that the preparation method is simple, the immobilization amount of the enzyme is large, the catalytic activity is high, the enzymolysis speed is high, the efficiency is high, the service life is long, and the biological micro-reactor can be reused.

The present invention belongs to the field of bioengineering technology, and especially a kind of couple producing biological diesel oil and 1, 3-propylene glycol. The present invention features that the course of lipase catalyzed reaction between methanol or ethanol and fat to produce biological diesel oil and the course of biologically converting glycerin into 1, 3-propylene glycol are coupled via membrane filtering for simultaneous proceeding. The present invention has the effects of eliminating the suppression of short-chain alcohol and glycerin on lipase, prolonging the service life of immobilized enzyme, omitting the glycerin separating and extracting step, lowering the production cost, saving time, raising production efficiency and providing economic and feasible process for producing biological diesel oil and 1, 3-propylene glycol.

The present invention provides a method of detecting changes in the refractive index at the surface of a localized surface plasmon resonance (LSPR) detection system. The method includes generating an insoluble product from an enzymatic substrate using an immobilized enzyme, wherein the insoluble product accumulates at a LSPR supporting surface. The method also includes detecting changes in the reflected or transmitted light of the surface arising from the presence of the insoluble product using LSPR.

A process for catalytic synthesis of the low-carbon alcohol ester of fatty acid from immobilized lipase includes such steps as immobilizing lipase to inertial carrier membrane or fabric, combining it with metallic wire mesh to form novel reactor, and catalytic esterifying reaction between fatty acid and alcohol at 20-60 deg.C for 14-24 hr. Its advantages are high esterifying rate up to 90-97%, less by-product and low energy consumption.

A multilayer enzyme immobilization process is provided comprising adsorbing a polyethyleneimine (PEI) solution in a fibrous matrix, and adding an enzyme to the fibrous matrix, which comprises a plurality of fibrils. The process further comprises forming at least two layers of PEI-enzyme aggregates on the fibrils, and cross-linking the multilayer PEI-enzyme aggregates. The process can further comprise washing the fibrils containing the cross-linked PEI-enzyme aggregates with distilled water and acetic acid buffer subsequent to cross-linking. However, the PEI-containing matrix is not washed prior to the addition of enzyme. The enzyme can be β-galactosidase and the fibrous matrix can be cotton cloth. The multilayer immobilized enzyme can be employed in a biocatalyst reactor for production of galacto-oligosaccharides from lactose and the hydrolysis of lactose to glucose and galactose.

The invention belongs to the biotechnology field and relates to a preparation method of genipin. The method comprises a preparation process of immobilized enzyme, a transformation process of gardenoside and a separation and purification process of genipin and is characterized by fermenting the strains for producing beta-glucosidase, collecting the fermentation liquor after reaching the enzyme producing peak, co-immobilizing enzyme and cells or enzyme and hyphae by combining embedding with crosslinking to prepare the immobilized enzyme, utilizing a packed-bed or stirred reactor to carry out catalyzed hydrolysis on the gardenoside and obtaining genipin after purification. The invention dispenses with separation and purification of the fermentation liquor, the immobilized enzyme obtained by preparation has high activity still keeping over 50% after operation for 960h and produces less pollution to the environment, genipin has high yield and the method has obvious advantages compared with other methods.

An amperometric biosensor is provided for determination of creatinine in a sample fluid. The biosensor can be an enzyme-polymer composition having at least one redox polymer and a plurality of enzymes immobilized on an electrode surface. Methods of preparing the amperometric biosensor are included. In addition, methods and systems using the amperometric biosensor in measuring creatinine concentrations of a patient and treatments of a patient with monitoring of the progress of dialysis performed on the patient are also provided.

The invention relates to an immobilized enzyme biocatalyst and the manufacturing method and application. The immobilized enzyme biocatalyst regards tubular hollow silica dioxide dielectric hole material as a carrier external surface, inner surface and micropore in the wall of which are fixed biological enzyme molecule. The method includes physical adsorption cast investment or chemical coupling/ crosslinking method; the biocatalyst is provided with good enzyme dispersibility and high carrying quantity, high recovery ratio of enzymatic activity, low enzyme flow rate. The invention can fix penicillin acylating enzyme, glucose oxidase, peroxidase, cytase and so on, which also can be used for removing sugar in protein, removing sugar in total egg, removing oxygen in food , microbiological sensing device, antibiosis and disinfection reaction, wherein immobilized penicillin acylating enzyme biocatalyst can be used to hydrolyze penicillin potassium and manufacture 6-APA.

The invention provides a transaminase mutant and applications of the transaminase mutant. The amino acid sequence of the transaminase mutant is the amino acid sequence with mutation as shown in SEQ IDNO:1, the amino acid sites with mutation comprise the T7C+S47C site. For the transaminase mutant with the mutation sites, the enzyme activity and/or stability are/is greatly improved, and the transaminase mutant can be applied in the relatively extreme environment. In addition, the transaminase mutant with the mutation sites can be further prepared into immobilized enzyme through the immobilization technology, the activity and the stability of the immobilized enzyme are relatively high, and the immobilized enzyme can be recycled for a plurality of times, and is suitable for being applied to continuous flow reaction of a packed bed.

The invention relates to a magnetic/functionalized SiO2 composite microsphere immobilized enzyme and a preparation method thereof, wherein, magnetic microspheres are cores, functionalized SiO2 is the shell, and the type and the content of functionalized groups, the particle size of the core in composite microsphere and the thickness of functionalized SiO2 can all be adjusted. The preparation method comprises the following steps: first synthesizing superparamagnetic microspheres, then treating the microspheres with hydrochloric acid, dispersing the microspheres in an ethanol/water alkaline system evenly by ultrasound, using tetraethoxysilane and silylating agent for further condensation and coating to obtain magnetic/functionalized SiO2 composite microspheres and performing absorbent immobilized and covalent immobilization to biological enzyme. The immobilized enzyme has fast magnetic responsiveness and good operational stability. The method has simple process and low cost and is applicable to industrialized production.

The invention relates to a preparation method of high purified fructo-oligosaccharide, in particular to a method for preparing the high purified fructo-oligosaccharide by using immobilized enzyme. The preparation method of the invention prepares immobilized fructosyltransferase, immobilized glucose oxidase and immobilized mimic hydrogen peroxidase; then prepared enzymes are used to prepare the high purified fructo-oligosaccharide through an interrupted or continuous production method. In the preparation method, cheap metalporphyrin compounds are used as the mimic hydrogen peroxidase to replace expansive catalase; the fructosyltransferase, the glucose oxidase and the mimic hydrogen peroxidase are all immobilized and all can be recycled and reused; the stability and the operating factor of the enzymes are improved; the production cost for preparing the high purified fructo-oligosaccharide is greatly reduced. The preparation method can use one step method to directly produce the high purified fructo-oligosaccharide from cane sugar.

The invention discloses an abietyl-containing terpolymer and a preparation method thereof, the chemical name of the abietyl-containing terpolymer is maleic rosin ethylene glycol acrylate-(methyl) acrylic acid-methyl methacrylate polymer. The preparation method is as follows: taking maleic rosin ethylene glycol acrylate, (methyl) acrylic acid and methyl methacrylate polymer as raw materials, and ethyl acetate as solvent, preparing the maleic rosin ethylene glycol acrylate-(methyl) acrylic acid-methyl methacrylate polymer by using a suspension polymerization method under the action of an initiator. The polymer has -COOH radicals, can be used for natural product separation such as separating berberine hydrochloride, ligustrazine hydrochloride and the like and used as the carrier of immobilized enzymes such as immobilized amylase, lipase and laccase.

The invention provides methods for preparing a stable, multiple-use three enzyme biosensor for the amperometric determination of creatinine in biological liquids that has a useful lifetime that extends significantly beyond that of presently available amperometric biosensors. The biosensor prepared by the methods of the invention encompasses a plurality of immobilized enzymes that are applied to the biosensor as an enzyme-polymer composition. The enzymes, which can include creatinine amidohydrolase, creatine amidinohydrolase and sarcosine oxidase, are immobilized into the enzyme-polymer composition simultaneously as well as applied to the biosensor simultaneously. Prior to being immobilized, the enzymes can be chemically modified by attaching one or more polyethylene glycol (PEG) chains per enzyme monomer. The polymer component can be provided by a polyurethane membrane. The invention also provides a method of preparing a biosensor that limits the diffusion of silver ions emanating the reference electrode, thereby preventing, contact between the silver ions and the enzymes. Related methods of preparing an enzyme-polymer composition for incorporation into a multiple use three enzyme biosensor for the amperometric determination of creatinine in biological liquids also are provided. The invention also provides multiple-use biosensors and enzyme-polymer compositions prepared by the methods disclosed.

The invention relates to a nitrogen-doped mesoporous carbon immobilized enzyme biosensing material and a preparation method thereof, which belongs to the field of biocatalysis and biosensing. Mesoporous carbon is prepared by taking mesoporous silica as a template and ethylenediamine, acrylonitrile or tripolycyanamide as a carbon-nitrogen source, and then nitric acid is used to modify the surface of the mesoporous carbon to obtain hydrophilically modified nitrogen-doped mesoporous carbon. The material has high specific surface area, large pore volume, large aperture and good biocompatibility, and also has good water and thermal stability and electric conductivity at the same time. The activity of enzyme molecules mobilized by taking the material as a carrier is well maintained. The biosensing based on nitrogen-doped mesoporous carbon immobilized enzyme has quick response time, wide linear range, high sensitivity, and low detection limit. In addition, a preparation process for the immobilized enzyme biosensing material is simple and controllable, and has the advantages of mild conditions, easily-obtained raw materials, and conventional equipment.

The invention discloses a carrier for immobilization as well as a preparation method thereof and immobilized beta-glucosaccharase. The carrier for the immobilization comprises magnetic nano particles, a carboxyl-rich composite material and transitional metal ions, wherein the carboxyl-rich composite material wraps the surface of the magnetic nano particles to form a carboxyl-rich shell, carboxyl on the surface is complexed with the transitional metal ions, and the transitional metal ions are combined with to-be-immobilized enzyme through a metal ion coordination bond. The preparation method comprises the following steps of (1) preparing the magnetic nano particles; (2) carrying out hydroxyl functional modification for the particles; (3) carrying out epoxy functional modification for the particles; (4) carrying out carboxyl functional modification for the particles; (5) complexing the particles with the transitional metal ions. The functional carrier is combined with beta-glucosaccharase through the metal coordination bond to obtain immobilized beta-glucosaccharase. The biological enzyme is firm in combination, high in enzyme activity, strong in operation stability and suitable for the mass production.

A composition is provided containing powdered cellulose and at least one water insoluble, immobilized water treatment additive. Preferably, a filter media composition is provided containing powdered cellulose and at least one water insoluble, immobilized enzyme such as lipase for filtration of swimming pool and spa water. The lipase may be recombinantly produced, and lipases having 1,3 positional or non-positional specificity are used. The immobilized lipase may be in the form of bead-shaped particles, and immobilization can be on a macroporous acrylic resin. Moisture may be added to the composition to provide a pre-moistened composition that is dustless and provides for improved dispersement and even filter grid coating. In a filtering system, the filter media absorbs oils contained in pool or spa water, and the lipase hydrolyzes the oils.

The invention discloses a method for preparing magnetic composite nanoparticles with a core-shell structure. In the method, electrostatic self-assembly and seeded emulsion polymerization are combined, wherein the electrostatic self-assembly is used to synthesize particles with the core-shell structure first and then emulsion polymerization is performed by using the particles with the core-shell structure seeds and using an initiator to prepare the magnetic composite nanoparticles with the sandwich core-shell structure which has three or more layers. The magnetic composite particles prepared by the method have a multi-layer sandwich core-shell structure, wherein in the structure, the core is a polymer microsphere, a Fe3O4 magnetic particle layer is in the middle, and different polymer layers are covered outside. The prepared particles have stable structures, strong and uniformly-distributed magnetism, smooth surfaces, controllable sizes, high stability and low cost, the thicknesses of the covering layers of the prepared particles can be controlled by nanoscale, and the adaptability of the prepared particles is high. Particles with specific surface groups can be prepared according to requirements and can be used in fields of biochemical separation, targeting preparation, immobilized enzyme, immunoassay, catalysis study and the like.

The invention provides a method for preparing a macroporous reticulated polyvinyl alcohol spherical vector. The method comprises the following steps: firstly, polyvinyl alcohol, calcium carbonate, sodium alginate and water are mixed in a certain mass proportion, and stirring is performed for full dissolution of the polyvinyl alcohol and uniform mixture, and then white PVA sol is obtained; secondly, the sol obtained is added into saturated boric acid solution containing 3 percent of calcium chloride by a peristaltic pump, and PVA gel beads are formed, cleaned by water and then placed into diluted hydrochloric acid solution for dipping until no air bubble is generated; thirdly, a spherical vector is thrown into glutaral pentanedial water solution and adjusted into acidity so as to generate crosslinking reaction to form a more stable crosslinking structure; and fourthly, the spherical vector is dipped into water and cleaned into neutrality, and then the white macroporous reticulated PVA spherical vector with elasticity is obtained. The macroporous reticulated polyvinyl alcohol vector prepared by the method has stable macroporous reticulated structure and good hydrophilicity, physical and chemical stability and anti-biological degradability, is suitable for immobilized enzymes and microorganisms so as to form a plurality of bed-shaped bioreactors, and is used in the modern bioengineering field such as sewage treatment and so on.

The invention relates to a method for preparing ginsenoside Compound-K, which belongs to the pharmacology field. The Compound-K is prepared by fermenting conversion with the ginseng total saponins as substrate by using fungus aerobiotic fermentation technology, immobilized cell technology, and immobilized enzyme technology, and the Compound-K is separated and purified. The content analyse and structure determination for the Compound-K are carried out. The detection results show that the structure of the product provided by the invention is coincident with the structure of the Compound-K.