117 results about "Dithiothreitol" patented technology

The invention belongs to the technical field of biology, and particularly relates to a reagent combination and a kit for extracting nucleic acid through a paramagnetic particle method and application of the reagent combination and the kit. The reagent combination or the kit does not adopt beta-mercaptoethanol with pungent smell or dithiothreitol needing to be stored at low temperature as an antioxidant, but adopts tris (2-formylethyl) phosphine hydrochloride and / or metabisulfite as an antioxidant, belongs to common salt chemical reagent powder, can be stored at normal temperature, and can be used for preparing a reagent for the first time. Manual addition by experimenters before an experiment is not needed, so that nucleic acid (RNA) released by splitting decomposition can be effectively prevented from being oxidized and denatured, and the integrity of extracted nucleic acid (total RNA) fragments is ensured; especially, the metabisulfite is commonly used in food additives, does not cause harm to the body, and is non-toxic and non-volatile.

The invention discloses a blood genome DNA extraction kit and an extraction method, and belongs to the technical field of nucleic acid extraction. The DNA extraction kit comprises a lysis solution, a first rinsing solution, a second rinsing solution and an eluent, wherein the lysate is prepared from the following components: 5.5 to 6 M of guanidine hydrochloride, 0.2 to 0.3 M of NaCl, 0.01 to 0.015 M of EDTA (Ethylene Diamine Tetraacetic Acid), 0.01 to 0.015 M of glucan, Triton X-100 with the volume concentration of 1.5 to 2 percent, 0.06 to 0.1 M of dithiothreitol, Tween-20 with the volume concentration of 5 to 10 percent and 10 to 50 mM of trehalose. The components of the lysate in the kit are optimized, through the synergistic effect of the components, the cell lysis efficiency is remarkably improved, meanwhile, DNA molecules higher in purity, more complete in structure and higher in extraction yield can be obtained, and therefore the kit has good application prospects.

The invention provides an additive composition containing a bioactive enzyme and a preparation method of the additive composition, and belongs to the technical field of biological enzymes. The preparation method comprises the following steps: fixing phytic acid and cyclodextrin on hydroxyapatite, modifying with tannic acid, reacting with dithiothreitol modified lysozyme to prepare an immobilized compound, adding 2, 2-dimethoxy-2-phenylacetophenone and methyl methacrylate, and carrying out irradiation reaction with an ultraviolet lamp to prepare the additive composition containing the bioactive enzyme. The broad-spectrum antibacterial property and the antiviral property of the lysozyme are greatly improved, the sterilization effect on gram negative bacteria is obviously improved, meanwhile, the stability of enzyme is greatly improved, the enzyme is not prone to inactivation, the preservation time of the enzyme is prolonged, the application effect of the enzyme is widened, meanwhile, the lysozyme has good killing capacity on oral bacteria and viruses, the addition of preservatives is reduced, and the cost is reduced. The cleaning effect and stability of the product are improved, tooth demineralization can be prevented, decayed teeth can be prevented, and wide application prospects are achieved.

The invention discloses self-repairing waterborne polyurethane based on double dynamic bond synergy and a preparation method thereof.The method comprises the following steps that 1, in the nitrogen atmosphere, after isophorone diisocyanate, polytetrahydrofuran diol and dimethylolpropionic acid react for a period of time, a catalyst is added for continuous reaction, and a prepolymer is synthesized; (2) adding N, N-di-tert-butyl ethylenediamine into the prepolymer, and carrying out chain extension reaction; (3) adding dithiothreitol into the solution after the reaction in the step (2) to carry out cross-linking reaction; and (4) adding triethylamine into the solution obtained after the reaction in the step (3), and carrying out a salt forming reaction to obtain the self-repairing waterborne polyurethane emulsion based on double dynamic bond synergy. High self-healing efficiency and mechanical performance are achieved by introducing dynamic covalent bonds with double thermal responses, and reprocessing and recycling are achieved at the same time.

The invention relates to a preparation method and application of a bismuth oxysulfide-hydrogel-melamine photo-thermal evaporator imitating a'sun cloth structure ', dithiothreitol and bismuth nitrate are dissolved in an organic solvent, a surfactant ligand is added, then a sodium hydroxide aqueous solution is added, after the reaction is finished, centrifugation, washing and drying are performed, and crystalline two-dimensional bismuth oxysulfide nanosheets are obtained; the preparation method comprises the following steps: adding bismuth oxysulfide nanosheets into a polyvinyl alcohol aqueous solution and glutaraldehyde, uniformly stirring, continuously adding a hydrochloric acid solution, continuously uniformly stirring to obtain a mixed liquid, pouring the mixed liquid onto a melamine foam skeleton, gelatinizing, freezing, drying, washing, and finally freeze-drying to obtain the 3D bismuth oxysulfide-hydrogel-melamine evaporator. The method has the advantages that the process is simple, the cost is low, by combining the photo-thermal conversion performance of bismuth oxysulfide and the unique sun-imitating cloth structural design, the sunlight capturing and conversion efficiency is improved, and efficient and stable solar photo-thermal seawater evaporation can be achieved.

The invention belongs to the technical field of biomedical materials and regenerative medicine, and relates to collagen-based injectable fiber hydrogel as well as a preparation method and application thereof. According to the injectable fiber hydrogel, methacrylated collagen and dithiothreitol are subjected to a thiol-ene click reaction rapidly under the action of a photoinitiator through illumination, a primary cross-linked network is formed, and the injection and in-situ gel forming requirements are met; then under the conditions that the pH is 6.5-8.0 and the temperature is 30-39 DEG C, collagen molecules are self-assembled into a nanofiber structure, and a bionic network similar to a natural extracellular matrix is obtained. The hydrogel disclosed by the invention has the advantages of rapid gelation, structural biomimetic property and biological activity; residual sulfydryl endows the hydrogel with active oxygen scavenging capacity, so that oxidative stress can be relieved, and immune response can be regulated; the fibrotic structure promotes cell adhesion, migration and tissue regeneration.

The invention provides a composite extraction agent and a method for separating gold in electroplating wastewater by using the composite extraction agent, and belongs to the field of wastewater purification, the composite extraction agent comprises an extraction main agent and an extraction main agent stabilizer, the extraction main agent is a diallyl sulfide compound, and the extraction main agent stabilizer is dithiothreitol. The extraction main agent can form a stable complex with gold ions to enter an organic phase, and a nonlinear space structure of the extraction main agent can realize selective coordination with the gold ions, so that coordination reaction with other impurity metal ions is avoided; the sulfydryl in the dithiothreitol molecular structure has reducibility, so that the residual oxidant or dissolved oxygen in the solution can be prevented from oxidizing the extraction main agent, and the nonlinear polysulfide structure of the extraction main agent is kept. According to the method, the heterogeneous interface-coordination reaction of the activation sites in the molecular structure of the extracting agent and the gold ions in the inorganic phase is ensured by regulating and controlling the multi-component components of the composite extracting agent, efficient selective chelation of target metal is achieved, and the purpose of separating and enriching the gold ions in the gold-containing electroplating waste liquid is achieved.

The invention relates to a preparation method of an oil-proofing agent based on polymerization of acrylic acid and organic silicon, and belongs to the technical field of polymer synthesis. The preparation method comprises the following steps: adding methyl acrylate, hydroxyethyl acrylate, dithiothreitol, m-trifluoromethylcinnamyl aldehyde and triethylamine into a reaction kettle, and stirring and heating to react; adding an initiator, and continuously reacting, so that the acrylic monomer is subjected to polymerization reaction to form a polymer with good stability and mobility; alpha, omega-dihydroxy polydimethylsiloxane is continuously added, the reaction is continued, and the organosilicon linear body and the polymer are subjected to a polymerization reaction; adding an emulsifier, stirring, mixing and reacting to obtain an oil-proofing agent; the oil-proof agent is added into the lunch box paper pulp and is uniformly stirred, so that the polymer is uniformly distributed on the surface of the lunch box paper pulp to form a compact oil-proof film, and the attachment of oil stains is effectively prevented; the oil-proof agent prepared by the invention has good oil-proof performance, can effectively prevent oil stain adhesion, and keeps food packages and tableware clean.

The invention relates to the technical field of microbial fermentation, and particularly discloses a culture medium for increasing the number of bradyrhizobium japonicum, application of the culture medium and a method for efficiently and stably culturing bradyrhizobium japonicum. The culture medium comprises the following components: 16-18g / L of glucose; 3-5g / L of yeast extract powder; 0.2 to 0.4 g / L of calcium chloride; 0.3 to 0.5 g / L of magnesium sulfate heptahydrate; 0.5 to 1g / L of monopotassium phosphate; 0.5 to 1 g / L of dipotassium phosphate; 0.1 to 0.2 g / L of sodium chloride; 5 to 7 ml / L of Rh trace element liquid; 0.0008 to 0.001 g / L of ferrous sulfate; the concentration of dithiothreitol is 0.5 to 1 g / L; and 5-10% of bovine serum. According to the application, DTT and bovine serum are added on the basis of optimizing a nitrogen carbon source and a nitrogen carbon source ratio, so that the bacterial count of bradyrhizobium japonicum is increased. Meanwhile, the invention further improves the culture method of the bradyrhizobium japonicum, so that the bacterial count of the bradyrhizobium japonicum is further increased.

The invention relates to a tubular incision enzyme premixed solution and application thereof, and belongs to the technical field of biology. The invention provides a tubular endonuclease premixed solution. The tubular endonuclease premixed solution is prepared from a solvent, restriction endonuclease, potassium acetate, magnesium acetate, NaCL, KCL, Triton X-100, bovine serum albumin, dithiothreitol, glycerol and trehalose. The tubular endonuclease premixed solution has the functions of buffering and enzyme digestion, and when the tubular endonuclease premixed solution is used for enzyme digestion reaction, the tubular endonuclease premixed solution is mixed with a DNA substrate and then incubated, so that an enzyme digestion product can be recycled, and additional calculation and component addition are not needed. Moreover, when the tubular endonuclease premix liquid is used for enzyme digestion reaction, the tubular endonuclease premix liquid containing different restriction endonuclease can simultaneously perform enzyme digestion on the same enzyme digestion object, the compatibility is strong, and normal enzyme digestion can be performed on the enzyme digestion objects with different volumes and different masses.

The invention relates to a DNA (deoxyribonucleic acid) ligation buffer solution and application thereof, the DNA ligation buffer solution comprises 5-15 mM of divalent metal ions, 0.5-5 mM of DTT (dithiothreitol), 10-15% of polyethylene glycol, 0.5-5 mM of ATP (adenosine triphosphate) and a Tris-HCl buffer solution, and the pH (potential of hydrogen) value of the Tris-HCl buffer solution is 7-9. The DNA ligation buffer solution can significantly improve the ligation reaction efficiency, and increase ligation products in the ligation reaction and the number of molecules capable of being sequenced during library construction.

The invention relates to a method for extracting genome DNA of plants rich in secondary metabolites and a buffer solution, and belongs to the technical field of molecular biology and botany. The method solves the technical problems of low DNA extraction efficiency, poor purity, easy degradation and the like when a traditional DNA extraction method is used for treating plant tissues rich in secondary metabolites such as alkaloid, polyphenol and the like. Comprising the following steps: adding a complexing agent such as polyethylene glycol or polyvinylpyrrolidone when grinding plant tissues in a liquid nitrogen environment; splitting by using a cell wall splitting buffer solution containing dithiothreitol and a nonionic surfactant; carrying out DNA release and extraction at 60-70 DEG C by adopting a CTAB (Cetyltrimethyl Ammonium Bromide) extraction buffer solution containing polyethylene glycol and papain; and then purifying and precipitating to obtain high-purity genome DNA (Deoxyribose Nucleic Acid). The method can effectively remove alkaloid, protein and other impurities, significantly improves the DNA yield and purity, and is suitable for genome sequencing, genetic resource protection, medicinal plant molecular identification and the like of plants with high secondary metabolites such as Stephania kwangsiensis and the like.

The invention belongs to the technical field of agricultural biology, and particularly relates to application of an endoplasmic reticulum protein antioxidant (reducing agent) in prevention and treatment of bombyx mori nuclear polyhedrosis virus. A screening test finds that the related endoplasmic reticulum protein antioxidants beta-mercaptoethanol (BME), dithiothreitol (DTT) and / or tris (2-carboxyethyl) phosphine (TCEP) have the effect of inhibiting the bombyx mori nuclear polyhedrosis virus (BmNPV), and the antioxidants interfere the replication and proliferation of the virus by destroying disulfide bonds in key proteins of the BmNPV, so that the bombyx mori nuclear polyhedrosis virus can be inhibited. The stability and activity of virions are directly influenced, so that the infection of the viruses on the silkworms is inhibited, a brand new thought is provided for the development of antiviral drugs of the silkworms, and the application value is good.

The invention discloses a bovine methane emission reduction method for intragastric delivery of targeted edition methanosarcina, and belongs to the technical field of biology. The method comprises the following steps: S1, preparing a conversion mixed solution: 50 mM of a PIPES buffer solution, 0.35 M of sucrose, 0.6 M of sodium chloride, 1 mM of magnesium chloride, 0.00001% of resazurin, 0.05% of cysteine hydrochloride, 1 mM of dithiothreitol, 40% of PEG4000 and 6 ml of PLL-PEG-DNA nanoparticles; s2, delivering the converted mixed solution into a ruminant rumen environment through intragastric administration; under the action of a conversion mixed solution taking polyethylene glycol 4000 as a main component, the gene editing system is delivered into methanosarcina, so that methanosarcina is modified, the number of methanosarcina in a bovine rumen is reduced, and the emission of bovine methane gas is further reduced.

The application discloses a marine-derived cholesterol oxidase and a preparation method and application thereof, and relates to the technical field of biology. The amino acid sequence of the marine-derived cholesterol oxidase (SkChOx) is shown in SEQ ID NO. 1 or 3, the specific enzyme activity of the marine-derived cholesterol oxidase can reach 31.9 U / mg, the marine-derived cholesterol oxidase has excellent anti-reverse performance, maintains high stability in the pH range of 5.0-10.0, has good temperature tolerance, organic solvent tolerance and metal ion tolerance, and exhibits unique salt activation effect and salt tolerance. The enzyme is compounded with dithiothreitol (DTT) and nonylphenol polyoxyethylene ether (NP-40) to form a liquid enzyme preparation, and after incubation at 37 DEG C for 7 days under accelerated conditions, the catalytic activity of the liquid enzyme preparation still remains about 87%, the liquid enzyme preparation has excellent long-acting storage stability, and has wide application prospects in the fields of clinical diagnosis, food physical and chemical inspection, biosensor development and industrial preparation of steroid drugs.

A test strip for detecting human chorionic gonadotropin in saliva and a preparation method therefor. Calculated based on 100 mL, a sample pad treatment liquid comprises the following ingredients: 1.0-1.5 g of Tris, 0.3-0.8 g of casein, 50-100 μL of Tween-20, 0.5-1.5 g of NaCl, 0.15-0.2 g of dodecyltrimethylammonium bromide, 0.8-1.2 g of 4-nonylphenyl-polyethylene glycol, 3.5-4.0 g of borax, 0.5-1 g of polyvinylpyrrolidone, 3-5 g of dithiothreitol and 0.8-2 g of L-cysteine. The sample pad treatment liquid is used to treat a sample pad, so as to reduce the interference of other impurity ingredients in saliva, thereby achieving the effect of completely eliminating non-specific reactions. The test strip has high sensitivity and good stability, can be stored for a long time at room temperature, and has the advantages of being cleaner and more convenient, allowing testing to take place at any time, being unaffected by sample collection time and place, etc.

The invention discloses a rolling circle amplification (RCA) molecular beacon based on DNA synthesized silver nanoclusters (AgNCs / DNA) and application of the rolling circle amplification (RCA) molecular beacon in DNA and RNA virus detection. According to the invention, a padlock template probe PlP with a specific secondary structure is used for carrying out two-enzyme one-step method RCA to generate single-stranded DNA containing a G-rich sequence tandem repeat element. Then H2O2 is added to eliminate the influence of residual dithiothreitol DTT in the RCA reaction, and then AgNCs / DT-GSP-t4 is used as a signal probe to generate a specific fluorescence enhancement signal for a to-be-detected target under the action of a G-rich proximity fluorescence enhancement effect. The RCA reaction does not need primer mediation, so that PlP design and RCA operation steps are simplified; meanwhile, the single-PlP or double-PlP probe is combined with the fluorescent molecular beacon, so that single-base mismatch at a PlP connection point can be recognized, and the probe has the advantage of high specificity.

The invention relates to a kit for constructing a sequencing library, and the kit comprises a repair treatment reagent which comprises a first enzyme with a repair function, NAD < + >, ATP, dNTPs and a first buffer solution; the connection treatment reagent comprises a second enzyme with a connection function, a joint and a second buffer solution; the digestion treatment reagent comprises a third enzyme with a digestion function; the first buffer solution comprises 10 to 50 mM of a Tris buffer solution, 5 to 120 mM of monovalent cations and 0.1 to 10 mM of divalent cations; and the second buffer solution comprises 20 to 100 mM of a Tris buffer solution, 5 to 20 mM of divalent cations and 1 to 10 mM of dithiothreitol. The kit provided by the embodiment of the invention is simple in composition, convenient to use and high in library yield, the library building cost is remarkably reduced, and wide application of three-generation sequencing can be powerfully promoted.

The present application discloses a method for increasing the oil accumulation in plants, aiming to solve the problem that there is a lack of new effective technical approaches for improving oil accumulation in current plants. The present application has found through research that endoplasmic reticulum stress induced by regulating chemical substances (tunicamycin, dithiothreitol, thapsigargin) or gene ( lew1 gene or its homologous gene) mutation can increase the oil content in plant tissues and seeds; increasing the oil accumulation in plants can effectively increase the oil content of oil crops or other plants, effectively increase the oil production of plants, and is of great significance to the production of vegetable oil.

The invention discloses algin lyase Alg0392, DNA, recombinant plasmid, recombinant bacteria, application and an algin cracking preparation, and relates to the technical field of microorganisms, the amino acid sequence of the algin lyase Alg0392 is shown as SEQ ID No.1, the algin lyase Alg0392 has endonuclease activity and exonuclease activity, can degrade sodium alginate into monosaccharide, disaccharide and trisaccharide, and the algin lyase Alg0392 can be used for preparing the algin lyase Alg0392. Meanwhile, the method has substrate specificity on polymannuronic acid, and sodium alginate can be well and thoroughly degraded. In addition, dithiothreitol and beta-mercaptoethanol have a promoting effect on the enzyme activity of alginate lyase Alg0392, and can be prepared into an alginate lysing preparation to improve the degradation efficiency of an alginate substrate.

The invention relates to the technical field of nucleic acid detection, in particular to a lysis buffer solution, a kit and an extraction method for extracting free DNA of peripheral blood. The lysis buffer solution for extracting the free DNA of the peripheral blood comprises a first lysis solution and a second lysis solution, the first lysis solution takes guanidine hydrochloride as a main chaotropic agent and at least one of ammonium thiocyanate and guanidine isothiocyanate as an auxiliary chaotropic agent, and is compounded with a metal ion chelating agent, trehalose, dithiothreitol, digestive enzyme, sodium dodecyl sarcosinate, borate and ascorbic acid; the second lysis solution takes guanidine hydrochloride as a main chaotropic agent and urea as an auxiliary chaotropic agent, and is compounded with a metal ion chelating agent, trehalose, dithiothreitol, digestive enzyme, sodium dodecyl sarcosinate, borate, ascorbic acid and polyethylene glycol. The buffer solution of the lysate does not contain SDS (sodium dodecyl sulfate), so that the residue of SDS in an extracted product can be avoided, and the amount of extracted free DNA (deoxyribonucleic acid) is more.

The invention provides a method for improving the purity of collagen in the fermentation process of engineering bacteria and application of the method, and relates to the technical field of fermentation. Dithiothreitol (DTT) is used as an exogenous additive for the first time to be applied to the process of producing collagen through strain fermentation, and it is found that DTT can relieve intracellular stress of yeast cells and effectively relieve the collagen degradation condition in the fermentation process, and a fermentation product with higher purity is obtained. The invention provides a novel method for producing collagen through fermentation of engineering bacteria, and the method is simple and easy to operate, can effectively improve the purity of a fermentation product, and has a wide application prospect.

The invention provides a preparation method of dithiothreitol, which comprises the following steps: step S1, carrying out epoxidation reaction on 1, 4-dibromo-2-butene and peroxy acid to generate 1, 4-dibromo-2-epoxidized butene; s2, carrying out a substitution reaction on the 1, 4-dibromo-2-epoxidized butylene and thioacetate, so as to generate 1, 4-diacetyl thio-2-epoxidized butylene, and carrying out a reaction on the 1, 4-dibromo-2-epoxidized butylene and thioacetate so as to generate 1, 4-diacetyl thio-2-epoxidized butylene; and S3, carrying out a hydrolysis reaction on the 1, 4-diacetyl thio-2-epoxidized butylene, so as to generate the dithiothreitol. According to the preparation method disclosed by the embodiment of the invention, 1, 4-dibromo-2-butene is used as a starting raw material, the epoxidation reaction is firstly carried out, then thioacetate is used for replacing bromine at the tail end, and finally the hydrolysis reaction is carried out to obtain the target product dithiothreitol, so that the whole synthesis route is short, the raw material is safe and non-toxic, impurities are easy to remove, and the preparation method is suitable for industrial production.

The invention discloses an enzyme activity detection reagent for plant alpha-ketoglutaric acid / Fe (II) dependent dioxygenase, a kit and application, and belongs to the technical field of biology. The enzyme activity detection reagent comprises a reagent I and a reagent II, wherein the reagent I comprises the following components: 1-5 mM of dithiothreitol, 0.1-1 mM of oxoglutaric acid, 0.1-1 mM of sodium ascorbate and 0.01-0.1 mg / mL of catalase, and sterilized distilled water is used as a solvent; the reagent II is prepared from 2 to 3 mg of FeSO4. 7H2O solid. Reagents for enzyme catalytic reaction are mixed according to a specific proportion to prepare the reagent I and the reagent II, the reagent I and the reagent II are directly subjected to one-time mixed reaction with a sample to be detected and a substrate during use, the operation is simple, convenient and rapid, the problems of errors, omission and the like caused by mixing reaction components for multiple times are avoided, and the detection accuracy is improved. And the method can also be used for detecting the enzyme activity of alpha-ketoglutaric acid / Fe (II) dependent dioxygenase of various plants, and has universality.

The present invention relates to a homocysteine ​​detection kit, comprising reagent R1, reagent R2, reagent R3 and reagent R4, wherein the reagent R1 comprises magnetic particles coated with S-adenosyl-L-homocysteine ​​antibodies and a basic buffer solution one; the reagent R2 comprises recombinant S-adenosyl-L-homocysteine ​​hydrolase and a basic buffer solution two; the reagent R3 comprises S-adenosyl-L-cysteine ​​conjugates and a basic buffer solution three labeled with a detectable marker; the reagent R4 comprises dithiothreitol and a basic buffer solution four; and further comprises a calibration product, the calibration product comprising an HCY antigen and a calibration product diluent, the calibration product diluent comprising a pH regulator, an inorganic salt ion, a surfactant and a stabilizer, and the stabilizer comprises bovine serum albumin. The homocysteine ​​detection kit has good stability, is easy to use and store, and can improve the accuracy of the test result.

The present invention relates to a method for treating keratin fibers, in particular human hair, comprising the following steps: - Application of a pretreatment agent (V) to the keratin fibers, wherein the pretreatment agent contains (V-1) at least one reducing agent selected from the group consisting of dithioerythritol, dithiothreitol, acetylcysteine, dimercaptosuccinic acid, thioglycerol, thiolactic acid, sodium dithionite, zinc dithionite, potassium dithionite, formamidine sulfinic acid, 2-hydroxy-2-sulfinoacetic acid and salts thereof, and - Application of a post-treatment agent (N) to the keratin fibers, wherein the post-treatment agent (N) contains (N-1) at least one organic silicon compound from the group of silanes with one, two or three silicon atoms.

The invention provides a mycobacterium tuberculosis rapid detection system based on digital CRISPR-Cas polydispersion liquid drops, the rapid detection system does not comprise a PCR amplification detection device, the system comprises a nucleic acid extraction subsystem, the nucleic acid extraction subsystem is used for heating a mycobacterium tuberculosis sample to be detected by using a PBS buffer solution containing dithiothreitol, and the nucleic acid extraction subsystem is used for extracting nucleic acid from the mycobacterium tuberculosis sample to be detected. Extracting mycobacterium tuberculosis DNA in a sample to be detected; a polydispersion liquid drop generation subsystem and a polydispersion liquid drop detection subsystem. The rapid detection system disclosed by the invention realizes on-site amplification-free detection of tubercle bacillus by combining rapid extraction of tubercle bacillus nucleic acid and a digital CRISPR technology.

The invention belongs to the technical field of ultrasonic imaging agents, and particularly relates to an ultrasonic contrast agent with low side effects, a preparation method and application. The ultrasonic contrast agent with low side effect provided by the invention is prepared from perfluorooctane, phospholipid, cholesterol, 0 cocamidopropyl amine oxide and dithiothreitol. Experimental data show that after being injected with the ultrasonic contrast agent, rats do not die and basically do not have toxic or side effect symptoms, after anatomy, visceral organs do not have obvious pathological changes, and the acute toxicity of the ultrasonic contrast agent is low.

The invention relates to a nucleic acid amplification kit and a nucleic acid detection method, the nucleic acid amplification kit comprises a nucleic acid extraction reagent, and the nucleic acid extraction reagent comprises the following components: Tris-HCl, NaCl, triethylenetetramine, dithiothreitol and a surfactant; wherein the working concentration of the Tris-HCl is 0.05 mol / L to 0.2 mol / L; the working concentration of the NaCl is 120 to 140 mM; the working concentration of the triethylene tetramine is 80 to 110 mM; the working concentration of the dithiothreitol is 3 to 6 mM; and the volume fraction of the surfactant is 0.1%-0.5%. According to the nucleic acid amplification kit disclosed by the invention, cells in a biological sample can be quickly cracked and high-concentration nucleic acid can be released, the released nucleic acid can keep certain stability, and the concentration meets the requirement of a subsequent direct expansion step; meanwhile, triethylenetetramine can be rapidly combined with protein impurities in cells, so that the triethylenetetramine cannot inhibit the activity of DNA polymerase.

This invention belongs to the field of rust-preventive coating material preparation technology, specifically relating to a water-based self-healing rust-preventive coating and its preparation method. First, an unsaturated ester, a fluorinated unsaturated ester, and 1,4-dithiothreitol are prepared into a fluorinated hydrophilic polymer under the conditions of an initiator, a chain extender, and water as a solvent. Then, the obtained fluorinated hydrophilic polymer is reacted in an aqueous phase to prepare a water-based fluorinated acrylic copolymer. Finally, the water-based fluorinated acrylic copolymer is compounded with modified CeO2 nanoparticles, iron oxide, talc, and antioxidant 168 to obtain a water-based self-healing coating material. This invention achieves self-healing of the coating material by introducing a D-A reaction, and uses water as a diluent, is non-toxic, odorless, harmless to humans, and does not pollute the environment. By introducing cerium groups, this coating improves the corrosion resistance of metals, greatly extending the service life of the material and possessing high application value.