1478 results about "Disulfide bonding" patented technology

This disclosure relates to dimeric immunotherapeutics that comprise two IgGs that are crosslinked with a disulfide bond. The two IgGs may be chimeras of two different heavy chains, in which one heavy chain includes a cysteine mutation that forms the disulfide bond, and the other heavy chain lacks the cysteine mutation. The presence of a cysteine mutation in only one of the heavy chains of an IgG avoids two disulfide bonds between the two IgGs, which increases the accessible orientations between the two crosslinked IgGs, and also avoids the formation of trimers and higher-order oligomers.

The invention provides a self-repairing polyurethane film containing a disulfide bond and a DA bond and a preparation method thereof, and the preparation method comprises the following steps: (1) adding an organic solvent into a three-necked flask, then dissolving dihydric alcohol, diisocyanate, a disulfide bond monomer and a DA bond forming monomer in the organic solvent, then adding a catalyst, and mechanically stirring uniformly; (2) introducing nitrogen into the three-necked flask to evacuate air, setting a reaction temperature, and carrying out a reaction under mechanical stirring; (3) in a nitrogen environment, dropwise adding a monomer II forming a DA bond into the solution obtained after the reaction in the step (2), and after the dropwise addition of the monomer II forming the DA bond is completed, setting the reaction temperature and reacting for a period of time; and (4) pouring the solution obtained after the reaction in the step (3) into a polytetrafluoroethylene mold, and drying to obtain the self-repairing polyurethane film. The self-repairing polyurethane film prepared by the preparation method disclosed by the invention has relatively good mechanical properties, relatively good self-repairing performance under mild conditions and high self-repairing efficiency.

The invention discloses silk fibroin composite gel and a preparation method thereof, and relates to the technical field of tissue filling materials. The preparation method of the silk fibroin composite gel comprises the following steps: preparing silk fibroin and carrying out amination modification on the silk fibroin to obtain aminated silk fibroin; carrying out dynamic cross-linking on the aminated silk fibroin and the oxidized sodium alginate through a Schiff base bond by adopting an enzyme catalysis cross-linking process to obtain a dynamic cross-linked network solution; adding a temperature-sensitive component into the dynamic cross-linked network solution, and uniformly mixing to obtain a temperature-sensitive-dynamic dual-network pre-gel solution with temperature responsiveness; loading the active component into the temperature-sensitive-dynamic dual-network pregel solution to obtain a composite gel solution; incubating the composite gel solution to obtain primary gel; after disulfide bonds are introduced into the primary gel, cross-linking strengthening and sterilization are carried out, and the silk fibroin composite gel is obtained. Through temperature-sensitive-dynamic dual-network design, active components and disulfide bonds are introduced to strengthen crosslinking, and the problems that traditional injectable gel is irreversible, single in function, prone to collapse after being filled and the like are systematically solved.

The preparation method of the composite soybean protein gel comprises the following steps: adjusting the pH value of an egg white protein solution, carrying out heat preservation, adding protein glutaminase to carry out hydrolysis reaction, centrifuging, collecting supernate, and freeze-drying to obtain deamidated egg white protein; adding TG enzyme into the soybean protein isolate and deamidated egg white protein solution for enzymatic cross-linking reaction, centrifuging after enzyme deactivation, collecting supernate, and freeze-drying to obtain compound protein powder; dissolving the composite protein powder in water, stirring, and heating to form composite soybean protein gel; according to the preparation method disclosed by the invention, glutamine in the egg white protein is hydrolyzed by using the protein glutaminase, so that only the site of lysine is reserved, and then TG enzyme treatment is performed, so that the crosslinking of the egg white protein is avoided, and the content of disulfide bonds in the soybean protein is increased, thereby remarkably improving the gel strength and compression resistance of the composite soybean protein thermal gel.

The invention relates to the technical field of automobile tires, and discloses a new energy automobile tire self-repairing sealing material adhered with mute cotton. The preparation method comprises the following steps: adding a modified polyurethane adhesive, C5 petroleum resin and a modified carbon nanotube filler into absolute ethyl alcohol, mixing to obtain a self-repairing liquid, adhering polyurethane cotton to the upper part of the self-repairing liquid, and drying to obtain the new energy automobile tire self-repairing sealing material adhered with the mute cotton. Disulfide bonds, boric acid ester bonds and imine bonds introduced into polyurethane through a chain extension reaction and diselenide bonds introduced into carbon nanotubes all belong to dynamic covalent bonds, so that the self-repairing performance of the material is improved; by introducing a rigid benzene ring and naphthyl aromatic structure, the mechanical property of the self-repairing sealing material is improved; the carbon nano tube can play a role in skeleton supporting in a polyurethane matrix, and the mechanical property of the material is further improved by introducing an adamantane rigid structure into the carbon nano tube.

The present invention relates to VHH antibodies that specifically bind to components of nuclear pore complexes of human cells and other species. Further, the present invention relates to the labelling of VHH antibodies through maleimide chemistry and ectopic cysteine residues. Further, the present invention relates to a method for forming a stabilizing, structural disulfide bond in initially reduced VHH antibodies.

The invention relates to a polypeptide ligand and a derivative of E3 ubiquitin ligase as well as a preparation method and application of the polypeptide ligand and the derivative, and relates to the technical field of biological medicines. The polypeptide ligand of the E3 ubiquitin ligase is characterized in that the amino acid sequence of the polypeptide ligand is shown as any one of SEQ ID NO: 1-3, and at least one disulfide bond is formed between cysteine residues in the amino acid sequence of the polypeptide ligand; the polypeptide ligand is combined with the E3 ubiquitin ligase RNF43 and / or the E3 ubiquitin ligase ZNRF3. The polypeptide ligand provided by the invention can be used for flexibly and modularly constructing various bifunctional molecules, such as small-size bifunctional molecules or bifunctional molecules with components which cannot be obtained through expression, so as to degrade disease-related membrane proteins, such as PD-L1, EGFR and the like, and has the potential of disease treatment.

The invention belongs to the field of electrochemical energy, and relates to polyurethane with self-repairing capability, a solid electrolyte, a composite electrode and a preparation method, a soft segment part of the self-repairing polyurethane-based solid electrolyte has good segment motion capability, and compared with polyethylene glycol, the crystallinity is greatly reduced; and the ionic conductivity and the lithium ion transference number are greatly improved. The dynamic disulfide bond and the hydrogen bond of the hard segment part jointly form a dynamic reversible macromolecular network, so that the mechanical strength is considered, and the tensile property, the self-healing property and the repeatable processing property are good. The self-repairing polyurethane-based solid electrolyte has relatively high ionic conductivity and lithium ion transference number, and can be cured on an electrode in situ to eliminate the interface contact problem of the electrolyte and the electrode, and the positive electrode and the negative electrode of the battery are healed into a whole through the self-healing capability of polyurethane, so that the performance of the battery is greatly improved, and the service life of the battery is prolonged. And the material has a good application prospect in all-solid-state lithium batteries.

The invention relates to the technical field of films, in particular to a flexible film special for a handwriting board and a preparation method of the flexible film. The flexible film is obtained by coating a release film with coating slurry and carrying out thermocuring, wherein the coating slurry contains modified polyurethane, a flatting agent, a defoaming agent and ethyl acetate. According to the modified polyurethane, polycarbonate diol, isophorone diisocyanate and other raw materials are subjected to a reaction, and a nano particle chain extender containing disulfide bonds is added. The nano particle chain extender containing disulfide bonds is prepared by modifying nano silicon dioxide and grafting cystamine dihydrochloride and diamino polyethylene glycol. Through nanoparticle surface modification and dynamic disulfide bond network construction, molecular-level coupling of a rigid reinforced phase and a flexible substrate, inhibition of nanoparticle aggregation and balance of strength and toughness are realized, the dynamic disulfide bond network can self-repair microcracks, and a high-quality special flexible film solution is provided for a high-performance handwriting board.

The embodiment of the invention relates to the field of energy storage, and provides a secondary battery and a preparation method thereof, an energy storage system and electric equipment. The negative electrode active material comprises a silicon-based material, honeycomb porous graphite and a polypyrrole layer, the surface of the honeycomb porous graphite is coated with the polypyrrole layer, the silicon-based material is embedded in pores of the honeycomb porous graphite, and the silicon-based material comprises silicon particles, a poly N-isopropylacrylamide layer and a disulfide bond-containing polyaniline layer. The poly (N-isopropylacrylamide) layer and the disulfide bond-containing polyaniline layer are coated on the surfaces of the silicon particles, the poly (N-isopropylacrylamide) layer is positioned between the silicon particles and the disulfide bond-containing polyaniline layer, and the honeycomb porous graphite comprises a graphite flake and a carbon layer which is positioned on the surface of the graphite flake and is of a honeycomb pore structure. The secondary battery formed by assembling the negative electrode active material disclosed by the invention has relatively high cycling stability, high temperature resistance, rate capability, gram volume and safety.

The invention discloses two-dimensional porous nano NiFe2O4 and a preparation method of a self-repairing noise-reducing anticorrosive coating of the two-dimensional porous nano NiFe2O4. The NiFe2O4 precursor is prepared by adopting a hydrothermal synthesis method, the nano NiFe2O4 with a stable and regular two-dimensional porous structure is prepared by high-temperature calcination, and the nano NiFe2O4 is rich in pores and relatively large in specific surface area. Polyester glycol, diisocyanate and disulfide are used as raw materials, addition polymerization is performed according to the molar ratio of 1: 2: 1 to prepare a polyurethane matrix, and key process parameters such as a reaction solvent, atmosphere, temperature and time are optimized. Chemical bonds such as disulfide bonds are introduced, so that the coating is endowed with excellent self-repairing performance, and meanwhile, the noise reduction capability and the anti-corrosion effect of the coating are remarkably enhanced. The two-dimensional porous nano NiFe2O4 reinforced polyurethane prepared by the invention provides a brand new design thought and technical path for the field of self-repairing noise-reducing anticorrosive materials.

The invention discloses a cyclic peptide compound as well as a preparation method and application thereof, belongs to the field of polypeptide synthesis and application, and particularly relates to full-protection peptide resin prepared by solid-phase synthesis. Carrying out cutting and monocyclization on the full-protection peptide resin to obtain monocyclic peptide; the monocyclic peptide is subjected to binary cyclization treatment to obtain a cyclic peptide compound Cyclo (His-Lys-Cys-Gly-His-Lys-Cys-Gly-, and a disulfide bond is in bridge connection with Cysamp; and the binary cyclization is cyclized under the action of iodine methanol and ascorbic acid. The cyclopeptide compound prepared by the invention has the advantages of low toxicity, good stability, good antioxidant effect and good anti-inflammatory effect, and the expression of type I collagen can be improved. Therefore, the invention has the advantages of low toxicity, good stability, good antioxidant effect and good anti-inflammatory effect, and can improve the expression of the type I collagen.

The invention provides a preparation method of a self-repairing waterborne polyurethane coating based on a synergistic effect of a dynamic disulfide bond and a pH response microcapsule. The preparation method comprises the following steps: step 1, preparing a dynamic disulfide bond-containing waterborne polyurethane (D-WPU) emulsion; step 2, preparing a pH response microcapsule; step 3, preparing a self-repairing waterborne polyurethane coating; a dynamic disulfide bond of the self-repairing waterborne polyurethane coating rapidly repairs macrocracks at 50-60 DEG C through mercaptan catalysis, and pH < lt > is caused by local corrosion of a pH response microcapsule; when the pH value is 4.0, cysteine is released, sulfydryl accelerates recombination of dynamic bonds, and amino enhances cohesive force of the coating and neutralizes H < + >. And in combination with a hydrogen bond network of the nanocellulose, the coating has low-temperature repair (the mechanical strength recovery rate is greater than or equal to 90%), high toughness (the water absorption rate is less than or equal to 2.1%) and long-acting corrosion resistance (the salt spray resistance life is greater than or equal to 600 hours), and is suitable for severe environments such as ocean engineering and new energy equipment.

The invention discloses a light-moisture dual-curing underwater epoxy coating with a self-repairing function as well as a preparation method and a construction method of the light-moisture dual-curing underwater epoxy coating. The epoxy coating comprises a component A and a component B, wherein the mass ratio of the component A to the component B is (1.5-3.5): 1; the component A is prepared from the following raw materials: bisphenol F type epoxy resin, dynamic disulfide bond modified polysulfide rubber, boron nitride nanosheet and silicon carbide nanowire hybrid filler, a photoinitiator and a silane coupling agent; the component B is prepared from the following raw materials: moisture-cured polyether amine, a boric acid ester bond cross-linking agent and hydrophobic modified graphene oxide. According to the invention, a light-moisture dual-curing mechanism is adopted, ultraviolet irradiation initiates rapid surface curing, and then environmental moisture permeates to complete deep curing. The material provided by the invention has the advantages of rapid curing, excellent self-repairing function, significantly improved underwater adhesion and good thermal conductivity, and provides a new solution for rapid repairing and long-acting protection of underwater structures.

The invention discloses a self-repairing nylon elastomer material as well as a preparation method and application thereof. The preparation method comprises the following steps: S1, polymerizing a nylon monomer in the presence of an amine end-capping reagent to prepare a double-amino-terminated nylon hard segment; s2, adding the double-amino-terminated nylon hard segment, the double-carboxyl-terminated polyether and / or polyester soft segment and a disulfide bond-containing chain extender into a reactor, adjusting the proportion of the raw materials, and polymerizing under an optional auxiliary A to obtain a double-amino-terminated pre-polymerized nylon elastomer; and S3, adding the double-amino-terminated pre-polymerized nylon elastomer and a dialdehyde chain extender into the reactor, and carrying out a reaction in the presence of an optional auxiliary agent B to obtain the self-repairing nylon elastomer material. According to the self-repairing nylon elastomer material provided by the invention, the nylon elastomer can be self-repaired in various environments through the synergistic effect of various dynamic covalent bonds, and the polymerization efficiency is remarkably improved.

The invention relates to the technical field of bioactive peptides, in particular to an antioxidant peptide based on mussel byssus, a preparation method, a preparation and application of the antioxidant peptide based on mussel byssus, the antioxidant peptide is designed and synthesized by referring to the structural characteristics of mussel byssus proteins mfp-3, mfp-5 and mfp-6, the antioxidant peptide comprises four sequences of MFP3-AP1, MFP5-AP2, MFP6-AP3 and MFP-Hybrid, tyrosine in the peptide is modified into DOPA through enzymatic modification, and the antioxidant peptide is prepared through enzymatic modification. The stability and activity of the antioxidant peptide are enhanced through disulfide bond formation, metal ion coordination, PEGylation and other modifications, and the antioxidant peptide has high DPPH free radical scavenging activity, ABTS free radical scavenging activity, hydroxyl free radical scavenging activity and iron ion reducing capacity, has a protective effect on the cellular level, can be prepared into a liquid preparation, a freeze-dried preparation or a micro-capsule preparation, and can be used for preparing the antioxidant peptide. The compound is expected to be applied to the fields of antioxidant health care products, cosmetics and medicines.

Herein is reported a method for the generation of multispecific antibodies directly on the cell-surface at the site of action by a half-antibody exchange reaction between two 2 / 3-IgGs or two 2 / 3-BiFabs destabilized in one half by asymmetric perturbing mutations fostering the generation of correctly assembled full length bi- or multispecific antibodies. The method is performed in the absence hinge region disulfide bonds in the starting 2 / 3-IgGs or 2 / 3-BiFabs.

The provided is a biomineralization material for treating dentin hypersensitivity and promoting epitaxial growth of enamel and a use thereof. The biomineralization material includes following raw materials in parts by weight: 5-72 parts of a film-forming protein or a PEGylated film-forming protein, 4-67 parts of a water-soluble disulfide bond exchanger and 1-21 parts of a pH regulator. The present application proposes for the first time that the disulfide bond exchanger (e.g., cysteine (Cys)) without any toxicity may react with the film-forming protein or PEGylated film-forming protein. When a protein nano-coating with a mineralization regulating function is formed, no large number of macromolecular protein aggregates can be generated to block the dentin pores. The biomineralization material can permeate deeply into the exposed dentin pores, with the depth of 200-500 μm (the sealing depth of the protein coating reacting with TCEP is only about 40 μm).

The invention belongs to the technical field of ocean engineering materials, and particularly relates to an underwater concrete self-repairing material containing dynamic disulfide bonds as well as a preparation method and application of the underwater concrete self-repairing material. The underwater concrete self-repairing material containing the dynamic disulfide bond comprises the following components in parts by weight: 50-70 parts of a hardening agent which is an epoxy prepolymer containing the dynamic disulfide bond; the water repellent agent comprises 20-35 parts of a curing agent and 1-3 parts of an accelerant. According to the underwater concrete self-repairing material containing the dynamic disulfide bonds, the epoxy prepolymer containing the dynamic disulfide bonds serves as a main network, the epoxy prepolymer is broken under the action of external force, and then new covalent bonds can be formed through spontaneous recombination to repair microcracks.

The invention discloses a preparation method and application of a zinc-bromine flow battery positive electrode material, and belongs to the field of zinc-bromine flow batteries. The preparation method comprises the following steps: dissolving aniline and a dithio compound in an acidic ice bath, dropwise adding a peroxy strong oxidant to generate a polyaniline-disulfide bond copolymer, dialyzing, and freeze-drying to obtain powder; then heating soluble silver salt, a reducing agent, a hydrophilic dispersing agent and an organic sulfydryl silane coupling agent to prepare functionalized nano-silver particles; the powder and nano-silver particles are dispersed in N-methyl pyrrolidone for ultrasonic treatment, and dynamic self-repairing coating slurry is prepared; and performing acid pretreatment on the carbon fiber paper, and performing electrochemical deposition on the slurry to prepare the zinc-bromine battery positive electrode material. According to the zinc-bromine battery positive electrode material, the coulombic efficiency and the voltage efficiency of a zinc-bromine flow battery are remarkably improved and the cycle life of the zinc-bromine flow battery is remarkably prolonged through methods of dynamic covalent bonds, nano-silver catalysis, a hierarchical pore structure, carbon fiber pretreatment and the like, and the zinc-bromine flow battery positive electrode material has chemical stability, efficient bromine adsorption capacity and excellent catalytic activity.

The invention discloses a bidirectional reversible conversion method and system between a peptide molecule SMILES and a sequence expression. The core innovation lies in that a new sequence description syntax is defined to retain information of a polypeptide special bond and specific modification of amino acid; a main chain atom index and adjacency traversal topology identification algorithm is adopted, and end group and topology integrated detection and coding are carried out; a residue recognition algorithm for main chain cutting and template library matching is compatible with any standard or non-standard amino acid residues, an extensible end group library / monomer template library and an automatic increment mechanism, and automatic recognition and sequence annotation of S-S disulfide bonds; the invention relates to a high-fidelity assembly algorithm of HELM anchor points and topology aware cyclic peptide processing. The method solves the problems of incapability of supporting a complex polypeptide topological structure, poor reversibility, insufficient expansibility of a monomer library and the like in the prior art, can be widely applied to scenes of quantitative structure-activity relationship model construction, large-scale polypeptide data cleaning and the like, and has remarkable practicability and innovativeness.

The invention provides a lipid compound based on a lipoic acid derivative, a composition as well as a preparation method and application of the lipid compound. When the lipoic acid-derived lipid provided by the invention is used as a delivery carrier of a nucleic acid drug, because disulfide bonds in the compound are split under the action of glutathione in cells, the compound is degraded, so that the timely release of nucleic acid is triggered, the cytotoxicity caused by accumulation of the compound in the cells is well reduced, and the bioavailability of the nucleic acid drug is improved. The biocompatibility is good. When the lipid nanoparticle composition is used as a carrier to deliver nucleic acid drugs, the lipid nanoparticle composition has excellent delivery efficiency and excellent spleen targeting performance, and the nucleic acid drugs can be preferentially delivered to the spleen.

The invention provides a respiratory syncytial virus F protein mutant and application thereof, and relates to the technical field of biology. The respiratory syncytial virus F protein mutant contains at least one recombinant F2-F1 polypeptide, each recombinant F2-F1 polypeptide independently contains a mutated fragment of an F0 polypeptide, and mutation comprises the following steps: (I) deleting positions 104-144 and substituting the positions 104-144 with a connecting peptide; (II) a 155C substitution, a 289C substitution, a 149C substitution and a 458C substitution; a disulfide bond is formed between 155C and 289C, and a disulfide bond is formed between 149C and 458C; and, (III) a 373R substitution. The respiratory syncytial virus F protein mutant has excellent immunogenicity, antigenicity, stability and tolerance.

The invention provides a respiratory syncytial virus antigenic polypeptide, nucleic acid and a vaccine. Compared with the respiratory syncytial virus wild type Pre-F protein, the respiratory syncytial virus antigenic polypeptide or the immunogenic fragment of the respiratory syncytial virus antigenic polypeptide has the following changes: the 104th to 144th regions of the Pre-F protein are replaced with GS linker; two groups of disulfide bonds are introduced into S155C, S290C, A149C and Y458C; the S190F and the V207L are used for realizing cavity filling; and P102A, L373R, I379V, M447V, P102A, L373R, the C terminal of the respiratory syncytial virus antigenic polypeptide or the immunogenic fragment thereof comprises a cytoplasm tail region fragment, and the cytoplasm tail region fragment is a fragment derived from 3-10 continuous amino acid residues of a PreF protein cytoplasm tail region. According to the present invention, the pre-F immunogenicity and / or stability can be improved, and the protein expression level can be easily improved.

The invention relates to a structural design, synthesis and application of a biomass carbon dot modified poly L-cysteine-S-S-carboxylic acid amphiphilic polypeptide. The invention provides a structural design, synthesis and application of poly (L-cysteine-S-S-carboxylic acid) amphiphilic polypeptide (P-L-cys) modified by biomass carbon dots (CDs). Comprising synthesis of P-L-cys which contains hydrophobic groups, provides hydrophilic and functionalized carboxyl and provides reduction response by disulfide bonds, synthesis of CDs and CDs modified P-L-cys (CDs (at) P-L-cys), and the macroscopic performance change of the polypeptide is explored from regulation factors of a polypeptide secondary structure and a self-assembly nanostructure assembly mechanism. The P-L-cys and the CDs (at) P-L-cys prepared by the invention have functionalization, fluorescence imaging and dual-response drug release and have particle sizes suitable for drug delivery and enrichment, and the CDs also provide a photo-thermal and photodynamic synergistic treatment effect and have good application prospects in the fields of drug delivery, cancer resistance and the like.

The invention relates to dithiolane modified beta-cyclodextrin, a preparation method thereof and application of the dithiolane modified beta-cyclodextrin as a drug carrier. The method comprises the following steps: carrying out acylation reaction on beta-cyclodextrin and lipoic acid, and modifying different numbers of dithiolane on the beta-cyclodextrin by changing a feeding ratio; the beta-cyclodextrin has a plurality of hydroxyl groups, and the activity of the hydroxyl groups at the C6 position is relatively high. The hydrophobic cavity of the dithiolane-modified beta-cyclodextrin can be loaded with a hydrophobic small-molecule drug, and the hydrophobic small-molecule drug can be loaded into the dithiolane-modified beta-cyclodextrin under the condition of heating reflux to form a nano-drug. The disulfide bond on the surface of the nano-drug and sulfydryl on protein or lipid on the outer side of a cell membrane are subjected to dynamic covalent thiol exchange, so that the nano-drug enters cells through a thiol-mediated cellular uptake way, endosomes and lysosomes can be avoided, the drug is quickly and directly delivered to the cytoplasm, degradation of the drug in the lysosomes is reduced, and the drug delivery efficiency is improved. The utilization rate of small-molecule drugs is improved, side effects are reduced, and better curative effects are achieved.

The invention discloses a washable easily-colored wool fabric treatment process, belongs to the technical field of wool fabric processing, and aims to solve the technical problem that the dyeing degree, the anti-felting performance and the color fastness of wool fabrics in the prior art need to be further improved. The method includes the following steps that disulfide bonds of wool fibers are opened through L-cysteine, the washable and easy-to-color wool fabric is obtained, the pretreated wool fibers prepared through the method are grafted with methoxy polyethylene glycol methacrylate under catalysis of hydrogen peroxide and horse radish peroxidase, modified wool fibers are obtained, and the washable and easy-to-color wool fabric is obtained. After the modified wool fibers are woven into the wool fabric, the wool fabric is respectively subjected to padding modification by using the modified dye solution and the finishing liquid, so that the degree of dyeing, the anti-felting performance and the color fastness of the wool fabric are improved.

The invention provides a chemically modified tetanus toxin C fragment as well as preparation and application thereof. The method for chemically modifying the tetanus toxin C fragment comprises the following steps: 1) reacting the tetanus toxin C fragment with a reducing agent to reduce a disulfide bond in the tetanus toxin C fragment; and 2) carrying out a reaction on the reduced tetanus toxin C fragment and an alkylation reagent, and carrying out modification. The recombinant tetanus toxin C fragment prepared by the method disclosed by the invention not only meets the quality standard required by pharmacopeia, but also has the advantages of stable conformation, high yield, easiness in amplification and low cost, and has a wide application prospect in the preparation of human vaccines, veterinary vaccines and antibody drugs and the development process of in-vitro diagnostic reagents.

The invention discloses an acidic lipase mutant with improved thermal stability and activity and application thereof.A semi-rational design strategy is adopted, disulfide bond and amino acid site mutation are combined, the lipase mutant with improved thermal stability and activity is obtained, then a combinatorial optimization strategy is adopted, efficient expression of LIPR is achieved in pichia pastoris, and the lipase mutant with improved thermal stability and activity is obtained. The biodiesel preparation capacity of the LIPR is evaluated, and the biodiesel yield is obviously increased through a continuous flow system. According to the invention, the development of reusable bio-enzyme catalysts is facilitated, and the bio-enzyme catalysts are used for producing biodiesel and other chemicals.

The invention belongs to the field of biological pharmacy, and relates to a temperature-sensitive hydrogel, in particular to a temperature-sensitive hydrogel SV (at) HP based on hyaluronic acid as well as a preparation method and application of the temperature-sensitive hydrogel SV (at) HP. The temperature-sensitive hydrogel SV (at) HP entraps CS-siRNA nanoparticles and VEGF (at) PLGA microspheres, and is used for realizing microenvironment responsive drug delivery to treat intrauterine adhesion. Chlorogenic acid and TGF beta1 siRNA are self-assembled through disulfide bonds to form CS-siRNA nano-particles, the CS-siRNA nano-particles are used for treating intrauterine adhesion through gene and chemical therapy, and cell and animal experiments prove that the CS-siRNA nano-particles have a good effect of improving intrauterine adhesion. Through evaluation of a real-time fluorescence quantification method, a western blot method, a cell scratch experiment, laser confocal microscope observation, inverted fluorescence microscope observation, an in-vivo experiment and the like, the SV-coated HP gel has the effects of resisting inflammation, improving endometrial fibrosis, promoting IUA rat endometrial angiogenesis and repair, inhibiting intrauterine adhesion and improving the intrauterine environment.