360 results about "Molecular modification" patented technology

Assays for detecting molecular modifications such as phosphate modifications and the presence and / or activity of enzymes and other agents involved in facilitating or otherwise regulating such modifications.

An optical sensor is provided, comprising (a) a silicon nanowire of finite length having an electrical contact pad at each end thereof; and (b) a plurality of self-assembled molecules on a surface of the silicon nanowire, the molecules serving to modulate electrical conductivity of the silicon nanowire by either a reversible change in dipole moment of the molecules or by a reversible molecule-assisted electron / energy transfer from the molecules onto the silicon nanowire. Further, a method of making the optical sensor is provided. The concept of molecular self-assembly is applied in attaching functional molecules onto silicon nanowire surfaces, and the requirement of molecule modification (hydroxy group in molecules) is minimal from the point view of synthetic difficulty and compatibility. Self-assembly will produce well-ordered ultra-thin films with strong chemical bonding on a surface that cannot be easily achieved by other conventional methods.

The invention relates to a preparation method of a graphene lubricating grease. The graphene lubricating grease as a compound is prepared from the following components in parts by weight: 100 parts of lubricating grease and 0.001 to 0.1 part of surface-modified graphene powder, wherein the surface-modified graphene powder is prepared by using a solvent method; a surface-modified coupling agent accounts for 0.5wt%-2wt% of the graphene powder; the graphene is dispersed in a solvent containing the coupling agent at the temperature of 30 to 60 DEG C and then is filtered and dried, thereby obtaining the modified graphene powder. As the method is used, the defects of poor mixing uniformity, low utilization rate, high addition quantity and the like in the prior art are overcome. By utilizing the characteristics of the graphene which is ultrathin, ultrahard and superlubricant as well as in corrosion resistance and high-temperature resistance, based on the higher molecular modification of the surface of the graphene and the high-dispersion mixing of the graphene with a lubricating agent, the graphene-based lubricating product is prepared. The graphene-based lubricating product can be used for obviously improving the lubricating performance of the lubricating agent, so that the friction and the abrasion of a mechanical movement surface are reduced greatly. Thus, the effects of material saving and energy conservation are realized.

The invention discloses an environment-friendly wood plastic floor and a manufacturing method thereof, and belongs to the technical field of floors. The environment-friendly wood plastic floor is prepared from the following components in parts by weight: 25-55 parts of PVC plastic raw materials, 30-50 parts of wood fibers, 12-18 parts of calcium carbonate, 0.8-1.2 parts of lubricant, 0.1-2.5 parts of plasticizer, 1.5-3 parts of titanate coupler, 1.8-2.5 parts of thermal stabilizer, 0.2-0.6 parts of anti-ageing agent, 1-2 parts of chlorinated polyethylene and 2-5 parts of acrylate impact modifier. The environment-friendly wood plastic floor is a composite material prepared by taking the PVC plastics and the wood fibers as main raw materials, performing high molecular modification and processing by mixing and high-temperature extrusion equipment, has main advantages of plastics and wood, and is mildew-resistant, ageing-resistant, acid-base-resistant, insect-damage-resistant, nontoxic and harmless.

The invention provides a biodegradable nontoxic amphiphilic multi-block polyurethane material which is formed by alternately copolymerize soft segments composed of polymer diol and hard segments composed of diisocyanate and a chain extender. Weight-average molecular weight of the biodegradable nontoxic amphiphilic multi-block polyurethane material is 5,000-100,000. The invention further provides a method for preparing the biodegradable nontoxic amphiphilic multi-block polyurethane material. The polyurethane material has a unique multi-block structure and amphiphilicity, can form a stable self-assembly micellar structure in water and easily introduces active sites at a main chain, a side chain and chain ends of polyurethane for molecular modification, and structure and performance of the polyurethane material is controllable. In addition, the polyurethane material has good biocompatibility and biodegradability with nontoxic degradation products, thus having wide application prospect in the biomaterial field, especially in the field of polymer drug and gene delivery fields.

The present invention relates to an analytical method and device utilizing magnetic materials and acoustics sensor. The invention employs a magnetic material modified with specific recognizable molecules to capture a substance in a sample and provides an external magnetic field to draw the magnetic material to an sensing region of an acoustics sensor, and then converts an effect occurred on a surface of the sensing region to an amount of the substance in the sample, wherein the effect is caused by a contact of the surface with the magnetic material and the substance.

The invention relates to an SERS (Surface Enhanced Raman Spectroscopy) method for detecting alpha fetal protein based on a probe-marked immunogold and magnetic composite material, and belongs to the technical field of protein analysis detection. The method comprises the following steps: combining P-thiosalicylic acid (MBA)-molecule-modified gold nanoparticle particles with an alpha fetal protein antibody, preparing a surface-functionalized Fe3O4@SiO2 magnetic composite material, absorbing the alpha fetal protein in serum onto the functionalized Fe3O4@SiO2 magnetic composite material; performing an immune reaction on an immunogold probe and the Fe3O4@SiO2 magnetic composite material modified with an alpha fetal protein antigen; performing Raman spectrum detection. The concentration of the alpha fetal protein can be detected by substituting the Raman strength value of an obtained Raman spectrum characteristic peak of protein to be detected into a working curve of Raman strength value and alpha fetal protein antigen concentration. The method has the advantages of ultrasensitiveness, high selectivity, mild detection conditions and the like, and has extremely important meanings in clinical analysis and diagnosis.

The invention discloses a novel environment-friendly high-molecular polymerized emulsion and a preparation method thereof. The polymerized emulsion comprises, by weight, 5 to 40% of a natural high-molecular polymer, 50 to 90% of a monomer, 0.02 to 5% of a modifier and 0.2 to 0.5% of an initiator, with the balance being water. According to the invention, the modifier is used to treat the high-molecular polymer to obtain a high-molecular modification compound having dispersion and emulsification effects during emulsion polymerization and used as a reducing agent for a redox initiation system. The compound and proper proportioned components consisting of the monomer, a water-soluble peralcohol and / or other water-soluble reducing agent undergo polymerization under certain conditions, so a light blue transparent polymer particle (micelle) dispersion system can be obtained, and soap-free polymer emulsions with different particle sizes and different core-shell structures can be synthesized. The polymerized emulsion provided by the invention has the characteristics of capacity of film forming at room temperature, excellent stability, nontoxicity, no odor, high activity and the like and can be widely used in fields like papermaking, printing, weaving, coatings, water-based paints, etc.

The invention specifically relates to a dendrimer-modified MOF material and a preparation method thereof, and application of the dendrimer-modified MOF material in enrichment of glycopeptides. The preparation method comprises the following steps: synthesizing a good-stability aminated MOF material of Mil-101(Cr) by using a hydrothermal method; and then grafting hydrophilic dendrimer polyamide-amine (PAMAM) on the surface of MOF by using a glutaraldehyde crosslinking method so as to obtain the dendrimer-modified MOF material. The dendrimer PAMAM for modification has a long chain and a great number of amino groups, so hydrophilicity of the dendrimer-modified MOF material is greatly improved, and the dendrimer-modified MOF material can improve enrichment efficiency when applied to enrichment of glycopeptides. In enrichment of a standard glycoprotein enzymolysis peptide fragment horseradish peroxidase (HPR), 13 glycopeptides is successfully enriched, and the dendrimer-modified MOF material has selectivity of 1: 100 and a detection limit as low as 1 fmol / [mu]L. The dendrimer-modified MOF material is novel, convenient, practical and highly efficient and has good repeatability, high stability and wide application prospects.

The invention relates to a preparation method and application of a low-molecular weight seaweed polysaccharide trace element chelate. The preparation method comprises the following steps: using seaweeds which abound in ocean and are low in price as raw materials, carrying out molecular modification on the raw seaweed materials by means of biological enzymes, and carrying out microfiltration and ultrafiltration to obtain a seaweed polysaccharide with a required molecular weight, wherein the obtained seaweed polysaccharide contains all varieties of polysaccharides contained in seaweeds; and enabling the seaweed polysaccharide and trace element metal ions to be subject to a chelation reaction so as to generate the low-molecular weight seaweed polysaccharide trace element chelate. The prepared new organic trace element product has the advantage that the product cost is greatly lowered. The filtrate generated in the preparation process can be used as the solvent for recycled use, and the invention can ensure that no poisonous waste is produced in the production process. The product can be used as a feed additive for various animals, the amount of the added trace elements can be decreased by more than 50%, and the amount of metal elements discharged in animal wastes can be decreased by more than 50%. By using the product, the growth performance of animals can completely attain or surpass the effect brought by adding inorganic trace elements of a large proportion. Thus, the culturing cost can be lowered.

The invention relates to a treatment method for enhancing stability of blueberry cyanidin. The treatment method comprises the following steps: extracting with a 0.5% trifluoroacetic acid (TFA) methanol solution, and sequentially purifying through an ion exchange resin column Amberlite XAD-7 and a Sephadex column Sephadex LH-20 to obtain a blueberry cyanidin refined substance; carrying out nutgall acylation reaction on the blueberry cyanidin refined substance and prepared triacetyl nutgall acyl chloride to introduce galloyl group with ortho-triphenolhydroxy group into the molecular structure, thereby obtaining the modified product nutgall acylated cyanidin. When high-performance liquid chromatography is used for determining the gallic acid amount generated after hydrolyzing the modified product, the nutgall acylation degree is 55-63%. The experiment proves that the stability of the modified product is obviously enhanced. The method for treating blueberry cyanidin is simple to operate, and has the advantages low cost, low pollution and high acylation degree. The molecular modification can enhance the primary characteristics of the blueberry cyanidin, so that the effects are enhanced; and multiple functional groups are introduced to endow the blueberry cyanidin with new physiological activity, thereby widening the application range.

The invention discloses protein-grafted natural polysaccharide, a preparation method and an application thereof, and concretely relates to bio-protein-grafted chitosan oligosaccharide, a preparation method and an application, which belongs to the high-molecular modification field. The bio-protein-grafted chitosan oligosaccharide is obtained by dissolved chitosan oligosaccharide and a bio-protein solution under effect of a catalyst microbial transglutaminase. According to the invention, reaction condition is mild, technology is simple, and the reaction substances are natural macromolecule with characteristics of environmental protection. The prepared water-soluble chitosan oligosaccharide bio-protein copolymer has good film forming ability, moisture-absorption effect, moisture-retention effect and antioxidation effect.

The invention discloses dendritic macromolecule modified gold nano particles as well as a preparation method and application thereof. The method comprises the following steps: performing azide modification on chitosan, and synthesizing glycan coupled dendritic polyamide-amine (CS-PAMAM) with alkynyl-containing dendritic polyamide-amine through a click reaction; and synthesizing gold nano-particleswith uniform grain size in one stop by using CS-PAMAM as a stabilizer and a reducer in one stop under the condition of not adding other reducer to obtain dendritic macromolecule modified gold nano particles having relatively small grain size. The gold nano particles have high stability and good biocompatibility besides favoring reduction of product cytotoxicity, massive amine functional groups are contained on the surface, target property is given to the gold nano particles, and an important application prospect is showed in gene transfer and tumor diagnosis integration. The dendritic macromolecule modified gold nano particles have excellent transfection, can be used as a medicine controlled-release vector, and has a potential application value in the field of medicine co-transfer.

The invention relates to biological functionalization degradable polyester and a preparation method thereof. The biological functionalization degradable polyester has the structural general formula shown as a formula (I) (described in the specification), wherein R1, R2 and R3 are one or more than one of hydrogen atom, alkyl, 1,2,3-triazole five-membered cyclized natural bioactive molecule; A is anatural bioactive molecule, x and y is 0 or an integral number more than 0; and n is 5-200; and the degradable polyester is prepared by virtue of 'click chemistry' reaction between biodegradable polyester containing alkynyl or azido and the natural bioactive molecule containing azido or alkynyl. The bioactive functionalization degradable polyester prepared by utilizing the 'click chemistry' in the invention has better molecule modification property and biocompatibility and has wide application prospect in the aspects of tissue engineering scaffold material, blood compatibility material, sustained or controlled release drug carrier and the like.

The invention discloses preparation of dendritic molecule-modifiedhydrophilic immunomagnetic beads and application of the hydrophilic immunomagnetic beads to rapid and efficient cell capture. The preparation method comprises the following steps: firstly, synthesizing magnetic nanoparticles through a hydrothermal method; hydrolyzing ethyl orthosilicate and modifying with a silylating reagent in order that the surface of a material is rich in amino groups; coupling dendritic molecules to the surface of the material in order that the material is hydrophilic; lastly, fixing an antibody to the surface of the material to prepare a capture substrate capable of recognizing tumor cells specifically. As proved by experiments, the hydrophilic immunomagnetic beads modified by the antibody and the dendritic molecules can shorten the time of combining the material and cells, perform high-specificity recognition and capture tumor cells rapidly, and capturing efficiency of 86+ / -5 percent can be achieved only in 15 minutes; meanwhile, the activity of the cells is kept, and the tumor cells can be successfully separated from whole blood into which a tumor cell standard is added. A template-free, low-cost and low-toxicity material is applied to cell capture, so that the method is novel, convenient, practical and efficient, and has a tremendous clinical application potential.

The invention belongs to the field of chemistry and chemical engineering, and particularly discloses a catalyst for selectively hydrogenating dimethyl terephthalate to prepare 1,4-cyclohexane dimethyl isophthalate and a preparation method and use method of the catalyst. The catalyst is Ru particles, and the surfaces of the Ru particles are modified with Ru-S and Ru-O coordinate bonds. The preparation method comprises the steps of solution preparation, a reduction reaction, sedimentation and washing, molecular modification and aftertreatment. Compared with the prior art, the catalyst is used for selectively hydrogenating dimethyl terephthalate to prepare 1,4-cyclohexane dimethyl isophthalate, better catalytic activity and target product selectivity are achieved, hydrogenation conditions are mild, and reaction time is shorter.

The invention belongs to the technical field of preparation and structural transformation of traditional Chinese medicine polysaccharide and relates to a preparation method of phosphorylated epimedium polysaccharide. The preparation method of the phosphorylated epimedium polysaccharide comprises the following steps: carrying out heating reaction on a phosphorylating reagent (sodium tripolyphosphate-sodium trimetaphosphate), epimedium polysaccharide and sodium sulfate for a period of time under alkaline condition, carrying out phosphorylation molecular modification, and selecting out optimal conditions for phosphorylation modification on the epimedium polysaccharide by carrying out a response surface experiment with content of phosphate radicals of products and reagent ratio, reaction temperature, reaction pH value and reaction time as factors. After the phosphorylated epimedium polysaccharide is prepared, in vitro activity of a modified product is studied, and results show that the phosphorylated epimedium polysaccharide has a certain immunoregulation, antiviral and antioxidant effects.

The invention discloses a method of the preparation for bimolecular-decorated nano probe, wherein one molecular is a recognition molecular and the other is an encode molecular; the obtained bimolecular-decorated nano probe detects bio-molecules in the way of sandwich-type combination; the sandwich-type combination is composed of three components of different functions:(1)a detection probe to generate signals,(2)a capture probe connected to a solid-state support, (3)a target part, through adding which, the detection probe and the capture probe can form sandwich-type combination with the bio-molecules, the bio-molecules to be detected, the capture probe and the detection probe form sandwich-type structure, and a clear detection signal can be obtained through detection after washing and removing impurities; with the method of sandwich-type hybridization, the bio-molecules to be detected can recognize its nano-probe combination and separate the samples, then encodes the molecule with mass spectrometric detection, thus qualitatively and quantitatively detects the bio-molecules in the samples to be identified quickly.

A method of increasing the work function of micro-electrodes includes providing a metal or silica surface functionalized with reactive groups and contacting the functionalized surface with a solution of at least one biochemical, having a permanent dipole moment and being capable of self assembly, for a sufficient time for the biochemical to self assemble molecularly (SAM) on the functionalized surface. The biochemical can be aminopropyl triethoxy silane, fatty acids, organosilicon derivatives, organosulfur compounds, alkyl chains, or dihosphates. Use in a wide variety of metals and metallic compounds is disclosed.

The invention discloses construction and application of a polygene knockout strain of Halomonas sp. TD01. The invention provides a recombinant strain which is obtained by inactivating one or more genes related to metabolic pathways of propionic acid in the Halomonas sp. TD01 used for producing polyhydroxyalkanoate (PHA). The one or more genes related to metabolic pathways of propionic acid are at least one selected from the group consisting of a coding gene for 2-methylcitrate synthetase, a coding gene for PHA digestive enzyme 1, a coding gene for PHA digestive enzyme 2 and a coding gene for PHA digestive enzyme 3. According to results of experiments in the invention, molecular modification is carried out on the Halomonas sp. TD01 to knock out 2-methylcitrate synthetase PrpC and three PHA digestive enzymes so as to obtain the novel recombinant strain, poly(3-hydroxybutyrate-co-3-hydroxyvalerate) (PHBV) with more excellent material performance can be highly efficiently produced by utilizing propionic acid, and the proportion of 3-hydroxyvaleric acid monomers in the produced PHBV and the conversion rate of the substrate propionic acid are substantially improved.

The invention relates to the field of nano materials, in particular to a preparation method and application of a functional photoacoustic probe based on assembly of gold nanoparticles. The preparation method of the functional photoacoustic probe includes the steps that peptide chains with one ends of -SH, the other ends of biotin and the middle parts of specific sequences DEVD are used for modification of the surfaces of the gold nanoparticles, meanwhile, functional micromolecules with one ends of -SH and the other ends of streptavidin are used for modification of the surfaces of gold nanorods, and the self-assembly process of the gold nanorods and the gold nanoparticles is completed by the specific biological coupling reaction of the streptavidin and the biotin. As an apoptosis enzyme caspase-3 can recognize and lyse the specific sequences DEVD of the peptide chains, the gold nanorods are separated from the gold nanoparticles, so that ultraviolet-visible absorption spectra and photoacoustic imaging signal strength begin to change; thus production of caspase-3 in tumor cells can be monitored with the method of photoacoustic imaging so as to judge the apoptosis process of the tumor cells after treatment, and the functional photoacoustic probe is also used for evaluating the effects of radiotherapy and chemotherapy, which has great significance in clinical medicine and disease diagnosis.

An optical sensor is provided, comprising (a) a silicon nanowire of finite length having an electrical contact pad at each end thereof; and (b) a plurality of self-assembled molecules on a surface of the silicon nanowire, the molecules serving to modulate electrical conductivity of the silicon nanowire by either a reversible change in dipole moment of the molecules or by a reversible molecule-assisted electron / energy transfer from the molecules onto the silicon nanowire. Further, a method of making the optical sensor is provided. The concept of molecular self-assembly is applied in attaching functional molecules onto silicon nanowire surfaces, and the requirement of molecule modification (hydroxy group in molecules) is minimal from the point view of synthetic difficulty and compatibility. Self-assembly will produce well-ordered ultra-thin films with strong chemical bonding on a surface that cannot be easily achieved by other conventional methods.

The invention relates to an improved beta-glucosidase gene and preparation of a recombinase thereof. The improved beta-glucosidase gene bgl II has an anucleotide sequence as shown in SEQ ID NO.1. Meanwhile, the invention provides a method for expressing the beta-glucosidase by the recombinant bacterium with a basic salt culture medium. Through artificial evolution and high density fermentation ofthe gene, the expression level of the improved aspergillus niger beta-glucosidase gene bgl II in Pichia pastoris is enhanced by 36 times compared with the original gene bgl I. The improved beta-glucosidase gene and preparation of a recombinase thereof in the invention can be used for molecular modification of beta-glucosidase gene and high density fermentation of its recombinant Pichia pastoris gene engineering bacterium, and can substantially improve the expression level of beta-glucosidase.

The invention discloses a high-bile salt resistance strain and bile salt hydrolase genes. The preservation number of the strain is CGMCCNo.8198. The strain has high acid resistance, high bile salt resistance, high nitrate reducing capability and the like. Three types of bile salt hydrolase genes of the strain are amplified, and are cloned, sequenced and heterogeneously expressed, so that generated bile salt hydrolases have high activity. The strain and the bile salt hydrolases can be used in the fields of food, medicine, agriculture and the like as food and feed leavening agents, microecological preparations, medicament expression carriers, feed additives and the like; the bile salt hydrolases can be developed into recombinant protein products, and can also be used for the molecular modification of lactic acid bacteria strains as selection markers of lactic acid bacteria gene engineering expression systems.

The invention discloses a preparation and an application method of magnetic nanoparticles modified by polylactic acid dendritic molecules in the technical field of biological engineering. The preparation method is that a coprecipitation method is adopted to prepare the magnetic nanoparticles; amino silane modifies the magnetic nanoparticles; generation 0.5 of polyamide dendritic molecules grows on the surfaces of the magnetic nanoparticles; the first generation to the tenth generation of the dendritic modules grow on the surfaces of the magnetic particles; the obtained magnetic nanoparticles modified by the dendritic molecules are dissolved in trichloromethane and the polylactic acid is added in the ratio of 2 to 1, constantly stirred and reacting, and then reduced pressure distillation is carried out to remove the trichloromethane and obtain thick liquid, thus obtaining the magnetic nanoparticles coated with the polyamide dendritic molecules and connected with the polylactic acid. The magnetic nanoparticles modified by the polylactic acid dendritic molecules and prepared by the invention have the advantages of the dendritic molecules and the magnetic nanoparticles, and the slow-release characteristics of the polylactic acid, thereby having the application value in gene or drug delivery.

The invention relates to a preparation method of a floor, and particularly relates to an environment-friendly wear-resisting waterproof polyvinyl chloride floor and a preparation method thereof. The environment-friendly wear-resisting waterproof polyvinyl chloride floor is made from polyvinyl chloride resin, chlorinated polyethylene, acrylonitrile-butadiene-styrene copolymer, bamboo-wood powder, calcium carbonate, a lubricant, a heat stabilizer, a foaming agent, a foaming regulator, a plasticizer, a plasticization modifying agent and an anti-aging inhibitor; raw materials are mixed, and then an obtained mixture is made into a polyvinyl chloride floor basal plate through extrusion molding; the polyvinyl chloride floor basal plate is adhered to a PVC (Polyvinyl Chloride) surface layer; an obtained product is divided and cut into a small plate, and then edge male and female grooves of the small plate are milled, so as to make the environment-friendly wear-resisting waterproof polyvinyl chloride floor. According to the environment-friendly wear-resisting waterproof polyvinyl chloride floor, the polyvinyl chloride resin, the calcium carbonate, the acrylonitrile-butadiene-styrene copolymer and the bamboo-wood powder are used as main raw materials, and are processed and made into a composite floor material through high molecular modification and by using blending and high-temperature extruding devices; the floor made of the material does not mildew, is anti-aging, acid-resistant and alkali-resistant, and moreover has quite good wear-resisting performance.

The invention relates to a preparation method of a DNA-directed gold nanocrystal. The preparation method comprises the following steps of firstly, modifying the surface of a gold nanorod with DNA molecules to prepare a gold nanorod / DNA compound, and then enabling tetrachloroauric acid and a reducing agent to generate in-situ reduction reaction in a solution system under the direction action of thegold nanorod / DNA compound to produce the gold nanocrystal. The invention also relates to the DNA-directed gold nanocrystal prepared by the preparation method. The position of a surface plasma resonance maximum absorption peak of the DNA-directed gold nanocrystal ranges between a 780nm visible light region and a 1100nm second infrared region. The invention also relates to application of the DNA-directed gold nanocrystal in malignant tumor photothermal therapy. Compared with the prior art, the preparation method of the DNA-directed gold nanocrystal has the advantages of easiness in realization,low preparation cost and capability of regulating the morphology and the performance of the gold nanocrystal.

The invention discloses a surface-modified silica / oxidized graphene nanocomposite and a preparation method thereof. The nanocomposite is prepared as follows: amide bonds are formed between silica nanometer particles with amino groups and a two-dimension oxidized graphene sheet by reaction between amino groups as well as carboxyl groups and epoxy functional groups which are at double sides of the two-dimension oxidized graphene sheet, in order to obtain the silica / oxidized graphene nanocomposite with covalent binding. The preparation method has the advantages of simple and easy technology and short reaction time; the nanocomposite has the advantages of regular structure, clear morphology, high yield, high purity, good stability and good organic dissolvability; the nanocomposite can be applied to high-molecular modification preparation of thermosetting resin, thermoplastic resin, rubber and other high-performance nanocomposites; the preparation method has the advantages of compact process, low cost, short reaction time and good identity of product structure, and the method can be applied to large scale industrial production.

The present invention provides a colorimetric method for detecting a polynucleotide strand binding molecule using one type of metal particles modified with a single type of interacting molecules. The interacting molecule is capable of specifically binding to nucleic and of protecting the metal particle from aggregation. Furthermore, the metal particles are capable of aggregation upon salt aggregation and / or cleavage of the interacting molecule, and colorimetric change changes upon aggregation.