130 results about "Self aggregation" patented technology

The invention relates to an acid amide-grafted sodium alginate nanometer material, a preparation method thereof and use thereof. The acid amide-grafted sodium alginate nanometer material comprises acid amide having an aliphatic chain and sodium alginate having a molecular weight of less than or equal to 50,000, and is characterized in that a carboxyl group of the sodium alginate is grated with hydrophobic acid amide by a chemical synthesis method for hydrophobic modification so as to form an amphipathic material, namely a modified sodium alginate nanometer material, having both hydrophobicity and hydrophilcity. The acid amide-grafted sodium alginate nanometer material performs self aggregation in deionized water to form nanoparticles, wherein the diameter of the nanoparticles is between 40 and 1,000 nanometers; under a condition of substituted ratio of 2 percent, the mean particle diameter of the nanoparticles is 596.2 nanometers; the medicament-loading rate is up to 40 percent; the medicament entrapment rate is up to 95.1 percent; and the medicament release time is as long as 6 days. The acid amide-grafted sodium alginate nanometer material can be used in a plurality of pharmaceutical fields as a slow release carrier of a plurality of medicaments, particularly hydrophobic medicaments, protein medicaments, polypeptides and vaccines.

The invention discloses a producing method for carbon nano tube / epoxide resin compound material, including steps of: processing the native carbon in the flowing bed jet mill, carboxylation, introducing polyatomic alicyclic amine with a flexibility structure on the carbon nano tube surface. The carbon nano tube / epoxide resin compound material is produced by mixing the epoxide resin and carbon nano tube by hot melt method, high speed stirring, ultrasonic treatment, then adding aromatic amine for solidification moulding. The advantages of the invention is that grafting polyatomic alicyclic amine on the carbon nano tube surface improves the surface function efficiency of the carbon nano tube, reduces the surface energy of the carbon nano tube, decreases the self-aggregation of the carbon nano tube, promotes both affinity and achieves organic connection of the carbon nano tube and epoxide resin by resin chemical reaction. The invention has a simple craft, a qualified mechanical property of obtained compound material, and an ulterior industry application convenient for the carbon nano tube.

The invention provides a method for purifying protein of enzyme aggregate based on self-aggregation short-peptide induction. The method comprises the following steps of: fusing and expressing a target protein, a peptide section (preferably intein) containing a cleavage site and a short peptide with self-aggregation function into a triplet in a sequence from left to right or from right to left, forming an enzyme aggregate in an expressing process, and separating from most soluble impurities in cell lysate by adopting a centrifuging or filtering method; and then releasing the target protein into solution by inducing cutting at a cleavage site so as to achieve the purpose of purification. The method has the characteristics of low cost and simple flow, can be used for laboratory-scale high-throughput protein purification and is also beneficial to industrial-scale protein production.

A preparation method of a Si / graphite / C composite material for lithium ion batteries includes the steps of: loading a nano silicon material on a carbon anode material base, and pyrolyzing organic or inorganic carbon by a high temperature pyrolysis method to coat the nano silicon material, so as to obtain the required Si / graphite / C composite material. The content of the nano silicon material is 1-69 wt.%, the content of the carbon anode material is 30-98 wt.%, and the content of the amorphous carbon layer coated with the nano silicon material is 1-10 wt.%. The silicon material with high dispersion structure loaded on the carbon material can effectively overcome the self aggregation of the nano material, and give full play to the characteristics of the nano material; and the carbon coated nano silicon material can improve the conductivity of the silicon material, promote the formation of a stable SEI film on the on surface of the silicon material, buffer the volume expansion of the silicon material, enhance the bonding strength of the silicon material with the carbon base, and improve the conductivity of the whole silicon carbon composite material. The preparation method is low in cost, simple for operation and applicable to large-scale industrialization production.

Nanoparticle compositions and methods are disclosed for the sustained release of small molecules, such as pharmaceutical compounds in vivo, for example ligand-lytic peptide conjugates. The construction of the nanoparticles helps to prevent self-aggregation of the molecules, and the consequent loss of effectiveness. The system employs layer-by-layer self-assembly of biocompatible polyelectrolyte layers, and layers of charged small molecules such as drug molecules, to form a multilayer nanoparticle in which the drug or other small molecule itself acts as one of the alternating charged layers in the multilayer assembly. The small molecules can then be released over time in a sustained manner. The LbL nano-assemblies can specifically target cancers, metastases, or other diseased tissues, while minimizing side effects.

The invention relates to a content acquisition of router cache nodes and dynamic routing request method in a CCN. In the method, the CCN comprises a content server, an access routing node and a plurality of intermediate routing nodes; the access routing node comprises a competitive domain and a cached domain. The method comprises the steps that the access routing node receives a content request of a user; the requested content is acquired from the content server or a cached node through the intermediate routing nodes according to the content request; the requested content is cached in the competitive domain, the frequency of content requesting is tested and counted in a testing period, and the frequency of content requesting is added into a header domain of a frequency package of the requested content; according to the LFU algorithm, the content of which request frequency is larger than the minimum access frequency is cached in the cached domain; the content of which frequency is smaller than the minimum access frequency is pushed up from the access routing node to the intermediate routing nodes along the path, for returning to the content server, indicated by a routing list.

The invention relates to a middle hole ZSM-5 zeolite microsphere and a preparation method thereof, which belong to the field of inorganic nonmetallic materials and catalyst preparation. The middle hole ZSM-5 zeolite microsphere is characterized by belonging to a microsphere with intracrystalline middle holes and intercrystalline middle holes and being formed by nanometer zeolites with the intracrystalline middle holes through self aggregation; the diameter of the microspheres is between 4mum and 8mum, the diameter of the nanometer zeolite grain is between 15nm and 50nm, and the diameter of the intracrystalline middle holes is between 3nm and 8nm. The microsphere is synthesized in the hydrothermal crystallization system by using nanometer silicon dioxide with the silanized surface as raw materials. The zeolite microsphere combines the advantages of the nanometer zeolite and the middle hole zeolite, overcomes the defect of difficult separation of the nanometer zeolite in the synthesis and use process and has uniform size, good sphericity degree, high hydrothermal stability and mechanical strength. The porosity of the middle holes can be regulated through changing the mol proportioning ratio of the organic silane coupling agents and silicon dioxide. The use of spherulization agents is avoided, the preparation process is simplified, and the preparation cost is reduced.

The invention discloses an enzyme-responsive self-aggregation luminous molecule and applications thereof in monitoring enzyme activity. The enzyme-responsive self-aggregation luminous molecule is formed by connecting a hydrolase substrate to an aggregation-induced luminous molecule, and can produce aggregation and induced luminescence after hydrolyzation under the action of the hydrolase. When the enzyme-responsive self-aggregation luminous molecule is added into living cells or extracellular reaction systems containing the corresponding hydrolase, the activity level of the hydrolase can be reflected through monitoring fluorescence signals by a fluorescence microscopic technology. The enzyme-responsive self-aggregation luminous molecule can be used for long-time space-time monitoring of the activity level of the hydrolase in cells.

The invention relates to new application of lactobacillus rhamnosus grx19, and discloses application of the lactobacillus rhamnosus in preparation of functional foods and drugs for regulating intestinal floras and preventing viral diarrheas. The lactic acid bacteria grx19 disclosed by the invention has good acid and bile salt tolerance and pathogenic bacteria inhibition, higher surface hydrophobicity, higher self-aggregation ability, and obvious adhesion for small intestinal epithelial crypt cells (IEC-6 cells) of rats shown by cell research. The lactobacillus grx19 disclosed by the invention has the effects beneficial to human health like general lactobacilli, and further can regulate the structures of the intestinal floras and prevent the viral diarrheas, thereby being used for production of the functional foods or drugs.

The invention discloses an electrode material. The chemical composition of the electrode material is LixMe1yMe2a(RO4)z, wherein Me1 is one of or composition of at least two of Mn, Fe, Ni, Co or V, Me2 is one of or composition of at least two of Mg, Mn, Cr, Ni or Al, R refers to P or / and Si, 1< / =x< / =4, 1< / =y< / =3, 1< / =z< / =5, and 0< / =a< / =0.2. The invention further discloses a preparation method of the electrode material. Small particles in solution uniformly wrap surfaces of large particles under the interaction of positive and negative charges of anionic dispersants and cationic dispersants, self-aggregation of the particles is avoided, the wrapping state cannot be destroyed in a precursor forming process, and the obtained electrode material is fine and uniform in crystal particle and good in electrical conductivity and cycle performance and is coated with a thin carbon layer on the surface.

The subject invention concerns novel and translatable materials and methods for expansion of stem cells, such as mesenchymal stem cells (MSC), that significantly improve translational success of the cells in the treatment of various conditions, such as stroke. The subject invention utilizes cell self-aggregation as a non-genetic means to enhance their therapeutic potency in a microcarrier bioreactor. The subject invention integrates a cell aggregation process in a scalable bioreactor system. In one embodiment of the method, thermally responsive microcarriers (TRMs) are utilized in conjunction with a bioreactor system. Cells are cultured in a container or vessel in the presence of the TRMs wherein cells adhere to the surface of the TRMs. Once cells are adhered to the TRMs they can be cultured at a suitable temperature for cell growth and expansion, e.g., at about 37° C. After a period of time sufficient for cell growth and expansion on the TRMs, the cell culture temperature is reduced so that the cells detach from the TRMs. The detached cells are allowed to form cell clusters that are then cultured under conditions such that the clusters aggregate to form 3D aggregates. The 3D aggregates can be collected and treated to dissociate the cells (e.g., using enzymatic treatment, such as trypsinization). Dissociated cells can then be used for transplantation in methods of treatment or for in vitro characterization and study.

The invention discloses a preparation method of a resistant starch nutritional carrier based on a metal-organic framework as well as a product thereof. The preparation method of the resistant starch nutritional carrier comprises the step of adsorbing metal-organic framework structured gamma-cyclodextrin on the surface of octenyl succinic anhydride modified starch (OSA-S) by taking the OSA-S prepared by performing esterification on octenyl succinic anhydride and resistant starch as a base material and under the effects of hydrogen bond, electrostatic force and the like, thus constructing the nutritional carrier with a porous network structure. The nutritional carrier has favorable solution self-aggregation performance; by virtue of the great load quantity of the relatively single OSA-S and the metal-organic framework structured gamma-cyclodextrin, functional substances such as nutritional elements can be embedded in a solid state mode, so that the damage caused by light irradiation, oxygen as well as acid-base and the like is prevented effectively, and a certain slow-release effect is achieved; the resistant starch also has a good health protection effect, and thus the nutritional carrier is expected to be a safe functional food additive applied to the food processing field.

Provided is a method of solubilizing a poorly soluble / insoluble active material through formation of an oligomer composite, in which a structure having a hydrophobic cavity structure is formed by using oligomers derived from two types of hydrophilic natural polymers and a poorly soluble / insoluble component is encapsulated in the cavity structure, and thus, self-aggregation of the poorly soluble / insoluble material is prevented and simultaneously, thermodynamic stability increases to effectively solubilize the poorly soluble / insoluble material. According to the constitution of the present invention, the method may include a first operation of preparing an oligomer composite having a cavity structure formed therein by mixing and dissolving oligomers derived from two types of hydrophilic natural polymers in water, and a second operation of adding a poorly soluble / insoluble material to the oligomer composite to encapsulate the poorly soluble / insoluble material in the hydrophobic cavity structure of the oligomer composite.

The invention discloses a self-aggregation short-peptide induction based immobilized nitrilase and a preparation method and application thereof. The preparation method comprises the following steps: (1) splicing connecting peptides and self-aggregation short peptides, so as to construct an expression vector; (2) connecting a nitrilase gene and the expression vector, and transforming into a recipient strain, so as to obtain an engineering strain; (3) carrying out induced expression on the engineering strain, carrying out wall breaking treatment on cells, and centrifuging and / or filtrating to obtain a precipitate, namely a nitrilase endoenzyme aggregate; (4) immobilizing the obtained nitrilase endoenzyme aggregate in alginate, thereby obtaining the immobilized nitrilase. According to the immobilized nitrilase aggregate obtained by the method, the particle diameter of the immobilized nitrilase is about 1mm. According to the immobilized nitrilase, particles can be subjected to freeze-drying preservation, and the enzyme activity is reserved to 90% when the immobilized nitrilase is preserved for 20 days at the temperature of 37 DEG C; the activity of the immobilized nitrilase is high, and the operating flow is simple.

The present invention relates to a method for preparing surface-functionalized cellulose nanospheres, which comprises (1) adding cellulosic fibers to the alkali liquor, swelling, filtering the solution, washing the product with water for several times until pH is 7, and drying to constant weight; (2) then adding the above product into mixed acid for fully infiltrating, reacting the above solution under stirring for 2-10 hours at 60-90 DEG C, naturally cooling the reaction products, adding an alkali solution until the pH of the solution is adjusted to 7 to obtain a dispersion liquid of cellulose nanospheres, then centrifuging the dispersion liquid, washing with water for three times, carrying out ultrasonic treatment, and then carrying out freeze drying to constant weight to obtain a cellulose nanospheres. The preparation method has advantages of low raw material cost, simple preparation process and mild preparation conditions; the surfaces of the cellulose nanospheres have functional groups, so that thermal stability and hydrophobicity are improved, self-aggregation is reduced, dispersion is easy, size is small, distribution is narrow, control is easy, specific surface area is large, reactivity is high and etc.

The invention belongs to the field of environmental water pollution abatement, and discloses a ZnIn2S4 nanosheet coated beta-Bi2O3 core-shell heterogeneous compound photocatalyst, as well as a preparation method and application thereof. According to the method, the ZnIn2S4 nanosheet coated beta-Bi2O3 core-shell heterogeneous compound photocatalyst is prepared by using ZnIn2S4 and synthetic beta-Bi2O3 monomer as raw materials through a simple self-aggregation effect. The binary ZnIn2S4 / beta-Bi2O3 compound nano-photocatalyst can be applied to catalytic degradation of tetracycline hydrochloride and methyl orange under visible light, shows excellent photo-induced electron separation efficiency, and can be used for improving the visible light utilization and integral photocatalytic activity. The ZnIn2S4 nanosheet coated beta-Bi2O3 core-shell heterogeneous compound photocatalyst is prepared from nontoxic raw materials, has simple operation and mild reaction condition, accords with the concept of environment-friendly chemistry, and has a wide application prospect in the aspect of solving water environmental pollution.

The invention discloses a water-soluble aminopolycarboxylic acid modified phthalocyanine compound as well as a preparation method and an application thereof. The water-soluble aminopolycarboxylic acid modified phthalocyanine compound is characterized in that the side chain or the center is connected to aminopolycarboxylic acid, the aminopolycarboxylic acid connected to the side chain is as shown in a structure (I) in the description, and the aminopolycarboxylic acid connected to the center is as shown in a structure (II) in the description. The preparation method of the water-soluble aminopolycarboxylic acid modified phthalocyanine compound is simple and easy to operate. After the phthalocyanines compound is modified by the method, the phthalocyanine compound has stable chemical property and can be completely dissolved in a sodium bicarbonate aqueous solution, the degree of self aggregation of phthalocyanine is reduced, and the phthalocyanine compound is absorbed in a 600-900 nm near-infrared zone and can be applied to the fields of near infrared fluorescence imaging or photodynamic tumor treatment.

The invention discloses a preparation method of distiller's grains activated carbon with high specific surface area. The method comprises preparation processes of carbonization, activation pretreatment, activation, aftertreatment and the like, wherein waste distiller's grains of a liquor factory are used as raw materials, and activated carbon with high specific surface area and high micropore rateis obtained by reasonably controlling carbonization and activation heating rate. Compared with another activated carbon production process in terms of modification of activated carbon, the preparation method has the advantages that high-performance activated carbon can be directly prepared by controlling the production process; the obtained activated carbon has large specific surface area, high micropore rate, strong adsorption capacity and the like, self-aggregation can occur after adsorption, and separation from a water body is facilitated.

The invention belongs to the technical field of biological medicine, and particularly relates to a method for preparing a protamine-deoxycholic acid conjugate with a heparin transfer function. The amidogen of protamine and the carboxyl of deoxycholic acid form an amide bond through teh effect of a cross-linking agent to prepare an amphipathic conjugate, and then the amphipathic conjugate and heparin form a self-assembled aggregation in order to conveniently release the heparin in cells. The hydrophobic modification of the conjugate can enhance the self-aggregation stability of nano-composites; the cationic performance of the conjugate entraps the heparin, so that the distribution capability of the heparin in the cells is increased, and the heparin is prevented from, degradation caused by the effect of heparinase and further the transfer of the heparin into cancer cells and the release and biological effect of the heparin in the cells are realized.

The invention discloses a p-benzoquinone condensation crystallization technology. The p-benzoquinone condensation crystallization technology comprises the following steps of 1, feeding p-benzoquinone crystal-containing steam in a stripping tower into a crystallization reactor by a tower top condenser and a Venturi tube, and carrying out crystallization, and 2, feeding a crystallization mixed liquid into the Venturi tube by a circulating pump so that the crystallization mixed liquid is mixed with the p-benzoquinone crystal-containing steam, and carrying out re-crystallization, or 3, selectively feeding the crystallization mixed liquid into a cyclone separator and a horizontal centrifuge and carrying out separation of a p-benzoquinone mother liquor and crystals. The Venturi tube has a negative pressure suction effect, prevents aggregation of non-condensable gas on the tower top, reduces a temperature of the stripping tower top, avoids p-benzoquinone self-aggregation coking and improves product purity. The crystallization mixed liquid ceaselessly washes a down-flow tube so that obstruction caused by crystals bonding to the wall of the down-flow tube is avoided. The p-benzoquinone crystal-containing steam and the crystallization mixed liquid are subjected to mixing and cooling so that a crystal color is brilliant yellow and crystal quality is improved.

The invention provides a preparation method of an antimicrobial functionalized chitosan derivative. The antimicrobial functionalized chitosan derivative is obtained by enabling chitosan and guanidineacetic acid to be subjected to an amidation reaction. The method comprises the following steps: (1) dissolving the chitosan in a diluted acid solution to obtain a chitosan and diluted acid water solution; (2) carrying out carboxyl activation on the guanidineacetic acid to obtain an activated guanidineacetic acid mixed solution; (3) mixing the mixed solution obtained in the step (2) with the chitosan and diluted acid water solution, and stirring for reacting; (4) adding hydroxylamine hydrochloride into reaction liquid for terminating the reaction; (5) filtering the reaction liquid and then carrying out dialysis in deionized water; after dialysis is completed, carrying out freeze drying treatment to obtain the antimicrobial functionalized chitosan derivative. The method avoids the problem of amino acid self-aggregation caused by carrying out guanidine functionalization by using arginine in the traditional method, and is simple in reaction process, mild in conditions and suitable for industrial production. The prepared antimicrobial functionalized chitosan derivative improves the antibacterial property and solubility while guaranteeing higher biological safety.

The invention discloses multi-drug self-aggregation composite nanoparticles as well as a preparation method and an application thereof. The multi-drug self-aggregation composite nanoparticles are formed by compounding at least one hydrophobic drug molecule and at least one water-soluble drug molecule, and are obtained through the following steps: dissolving the hydrophobic drug molecule in a good solvent to obtain a hydrophobic drug molecule solution; sequentially or simultaneously adding the hydrophobic drug molecule solution and the water-soluble drug molecule solution into a poor solvent of the hydrophobic drug molecule; heating, and performing magnetic stirring and ultrasonic treatment. The multi-drug self-aggregation composite nanoparticles contain no carrier, have high drug loading capacity and have no potential toxic or side effect brought by the carrier; the preparation method of the multi-drug self-aggregation composite nanoparticles are easy to operate and can be widely applied; the obtained nano-drug has a uniform size and a synergistic treatment effect.

The invention discloses an eye antifungal nano-micelle solution containing terbinafine hydrochloride. The eye antifungal nano-micelle solution consists of the following raw materials in parts by weight: 0.05-1 part of terbinafine hydrochloride, 0.5-10 parts of a solubilizer, 0.5-10 parts of glycerinum, 0.003-0.05 part of a bacteriostatic agent, 0.05-0.2 part of a thickening agent and 90-99.8 parts of water. According to the eye terbinafine hydrochloride antifungal nano-micelle solution disclosed by the invention, terbinafine hydrochloride nano-micelle is prepared from the solubilizer by self aggregation, the average particle size of the terbinafine hydrochloride nano-micelle is smaller than 30nm, the characters are not greatly changed after the terbinafine hydrochloride nano-micelle is subjected to freezing redissolution and boiling sterilization for 30 minutes and then cooled to room temperature, and the physicochemical properties are also stable. Water is taken as a solvent of the eye antifungal nano-micelle solution, and no organic solvent is used in the preparation process, so that the eye antifungal nano-micelle solution is small in irritation, relatively convenient to drop into eyes, free of phenomenon of adhesion or fuzziness, relatively long in eye acting time, relatively good in absorption by eyes, and relatively good in antifungal effect, and use comfort degree of patients can be greatly increased.

An immunological analyzing reagent comprising a composition containing a biotin-conjugated antigen or antibody against a substance to be analyzed, and a composition containing an avidin-conjugated microparticle, wherein the biotin-conjugated antigen or antibody contains an amount of biotin which does not substantially agglutinate with the avidin-conjugated microparticle in the absence of the substance to be analyzed, is disclosed. Further, an immunological analyzing method comprising the steps of: bringing into contact a sample, a biotin-conjugated antigen or antibody against a substance to be analyzed, and an avidin-conjugated microparticle, the biotin-conjugated antigen or antibody containing an amount of biotin which does not agglutinate with the avidin-conjugated microparticle in the absence of the substance to be analyzed; and detecting the degree of aggregation between the avidin-conjugated microparticle, and an immunocomplex formed from the substance to be analyzed and the biotin-conjugated antigen or antibody, is disclosed. According to the immunological analyzing reagent and analyzing method, a procedure in which an antibody or antigen is carried on a latex particle is not necessary; self-aggregation of latex particles does not occur; a precise measurement of the substance to be analyzed may be carried out; and an excellent reactivity the same as or superior to that obtained by the conventional sensitized latex method may be obtained.

The invention relates to homodimers for synthesizing a series of caffeic acids and ferulic acids. Structural formulas of the homodimers are as shown in a formula (I). The inhibiting effects and the free radical scavenging capacities of the homodimers on beta-starch amyloid protein self-aggregation can adjusted through an exchange joint, so that the homodimers can simultaneously act on a plurality of targets, and can be prepared into appropriate drug dosage forms for treating parkinson's disease, and diseases related to the beta-starch amyloid protein and oxidative stress.

The invention relates to a preparing method for antioxidant-modified carbon nano tube / hydrogenated butadiene-acrylonitrile rubber. The preparing method comprises the steps that firstly, a hindered phenol antioxidant is grafted to the surfaces of carbon nano tubes through a solid phase reaction from the angle of the molecular structure, then the antioxidant-modified carbon nano tube filler, hydrogenated butadiene-acrylonitrile rubber, a vulcanizing agent, an activating agent and a co-vulcanizing agent are mixed and vulcanized, and the product is obtained. The hydrogenated butadiene-acrylonitrile rubber prepared with the method has excellent mechanical properties, high-temperature resistance and hot oxygen aging resistance; besides, the antioxidant is not prone to self-aggregation and not likely to be separated from the rubber material, and thus the rubber product can have more stable performance; furthermore, no organic solvent is adopted, and environment friendliness of the preparing process is achieved.

The invention relates to a serum albumin with a metal chelating function as well as a preparation method and an application in inhibition for the aggregation of beta-amyloid proteins. The serum albumin with the metal chelating function is obtained through modifying 1,4-butanediol diglycidyl ether on an amino group on the surface of a serum albumin at first, and then modifying a metal chelating agent iminodiacetic acid on an epoxy group of 1,4-butanediol diglycidyl ether, and the average modification number of iminodiacetic acid on each serum albumin ranges from 2 to 40. According to the serum albumin with the metal chelating function, which is disclosed by the invention, the chelating capacity of the serum albumin for metal ions is improved, and then the self-aggregation of the beta-amyloid proteins and an aggregation process of the beta-amyloid proteins under the induction of the metal ions are inhibited, and the cytotoxicity of beta-amyloid protein aggregates is reduced. The serum albumin with the metal chelating function is used for a medicine for treating the diseases related to beta-amyloid protein aggregation. The medicine is used for treating and slowing down Alzheimer disease and other diseases.

A rectangular sedimentation tank includes a hopper portion in an upstream side and a floor inclination portion in a downstream side. The tank comprises: a vertical baffle formed at a side portion of the hopper portion; a vertical screening plate provided in a position corresponding to about 30 to 100% of a horizontally cross-sectional area of top of the hopper portion; and a horizontal baffle provided between the vertical baffle and the vertical screening plate. With the tank, contaminated water can be treated cost-effectively and efficiently.

The invention discloses a protocatechualdehyde cross-linked collagen hydrogel and a preparation method thereof. The method comprises the following steps: firstly, a collagen solution is subjected to hatching treatment to form collagen fibers by self assembly, and then the collagen fibers are soaked into a protocatechualdehyde solution for a grafting reaction; secondly, a sodium periodate solutionis added to make protocatechualdehyde in the protocatechualdehyde solution perform an oxidation self-aggregation reaction, so that intermolecular cross-linking is formed among the collagen fibers; andfinally, purification treatment is performed, and therefore the protocatechualdehyde cross-linked collagen hydrogel is obtained. According to the preparation method of the protocatechualdehyde cross-linked collagen hydrogel provided by the invention, the protocatechualdehyde is adopted as a cross-linking agent, aldehyde groups of the protocatechualdehyde react with free amino groups in collagen lysine to graft catechol groups on collagen molecules, unreacted protocatechualdehyde molecules react with the catechol groups grafted onto the collagen molecules to form cross-link bonds among the collagen molecules through oxidation self aggregation, so that the three-dimensional network structure of the collagen fibers is reinforced, and the mechanical properties and resistance to enzymatic hydrolysis of the collagen hydrogel are reinforced.

The invention relates to the technical field of heat conductive films, and discloses a PET / graphene heat conductive film based on thermal curing and a preparation method thereof. According to the heatconductive film, graphene quantum dots are added to the PET / graphene heat conductive film to effectively reduce the coacervation among graphene, a three-dimensional net-shaped structure is formed through chemical crosslinking or physical crosslinking by organic monomers through a gelcasting technology, and the graphene is immediately wrapped and isolated by polymer molecules or polymer monomers to effectively overcome the occurrence of the self-aggregation of the graphene; the thermal diffusion coefficient of the graphene of the prepared PET / graphene heat conductive film is 8-12 cm<2> / s, andthe thermal conductivity is 1300-1700 W / m k.