33results about How to "Simplified purification steps" patented technology

The invention provides a synthesis method of tilpotide. The synthesis method comprises the following steps: carrying out a reaction on Fmoc-Linker-OH, HBTU and a swelling AM Resin to prepare Fmoc-Linker-AM Resin, and carrying out a reaction on the Fmoc-Linker-OH and the HBTU and the swelling AM Resin to prepare the tilpotide. Adding Fmoc-Ser (tBu)-OH and HOBT into a reaction system of the resin and the PIP / DMF, and completely reacting; sequentially completing coupling from the C end to the N end to obtain full-protection peptide resin; adding a cracking reagent into the full-protection peptide resin, reacting, collecting filtrate, cooling, precipitating, and drying to obtain crude peptide; the problem that in the prior art, a linker on MBHA Resin is broken to generate new impurities is solved. The defect of using heavy metal palladium or genotoxic substance hydrazine hydrate is avoided; the problem that [-(Pro-Pro)] deletion impurities are generated by step-by-step coupling of C-terminal Pro36, Pro37 and Pro38 is solved; finished products are saved, and industrial production is facilitated.

The invention belongs to the technical field of environmental pollutant analysis and detection. The invention discloses a Fenton reaction-based efficient separation and extraction method for soil micro-plastics. The method comprises the following steps: preparing a micro-plastic soil sample; carrying out digestion and purification treatment on the micro-plastic; then separating the micro-plastics through a density flotation method; and finally, carrying out microscopic observation on the dried filter membrane by using a stereoscope so as to calculate the abundance of the micro-plastic and analyze the morphological characteristics of the micro-plastic. According to the method, the salt solution with lower cost and the organic matter digestion method with small influence on the micro-plastic particles are used, efficient removal of organic matter in the complex soil matrix and efficient extraction of the micro-plastic are achieved, the micro-plastic separation and extraction time is shortened, the micro-plastic recovery rate is increased, and the method is easy and convenient to operate, economical and practical.

The present invention provides a plant expression method of type III human collagen, an intron-containing coding gene and its application. The method comprises: step A: adding intron fragments to 16 gene fragments of collagen to construct the collagen COL3A1 gene; step B: connecting and synthesizing, and at the same time, achieving type III human collagen targeting to the apoplast by adding a signal peptide to achieve extracellular expression of type III human collagen; step C: transgenic expression of collagen; step D: culturing and purifying the best expressing plant seeds in step C. The present invention expresses type III human collagen in the apoplast, simplifies the purification steps, reduces costs, and the optimization of adding introns significantly enhances the stability of collagen expression.

The present invention discloses a recombinant Escherichia coli producing α-amino acid ester acyltransferase, a construction method and an application thereof, and belongs to the field of biotechnology. The recombinant Escherichia coli is deposited in the General Microbiological Center of the China Microbiological Culture Collection Administration Committee, with a deposit address of No. 3, Yard No. 1, Beichen West Road, Chaoyang District, Beijing, a deposit date of March 22, 2024, and a deposit number of CGMCC No. 30105. The recombinant Escherichia coli constructed by the present invention can produce α-amino acid ester acyltransferase, and the enzyme is used to catalyze the synthesis of glutathione, with a conversion rate of up to 82.59%, which is of great significance to the industrial development of biosynthesis of glutathione.

The invention provides a method for synthesizing carboxymethyl cellulose by a slurry method based on a novel etherifying agent and an application, the method comprises the following steps: adding crushed cellulose into a reaction container filled with an organic solvent, stirring, continuously introducing nitrogen into the reaction container, and when the temperature of the reaction container reaches 25-35 DEG C, stirring for 2-3 hours; slowly dropwise adding a sodium hydroxide aqueous solution into the reaction container, keeping the temperature for a period of time, rapidly raising the temperature of the reaction container to 55 DEG C, slowly adding a novel etherifying agent into the reaction container, controlling the temperature of the reaction container to be kept at 55-75 DEG C, placing the reaction container at 65 DEG C after dropwise adding, and keeping the temperature for a period of time; wherein the novel etherifying agent is low-carbon alcohol chloroacetate or chloroacetamide, an acidic material is added into a reaction container to adjust the pH value of a reaction system to 6.5-7.5, washing liquid is used for multiple times to obtain carboxymethyl cellulose, and the novel etherifying agent is adopted to solve the problems of a traditional etherifying agent. And the high-quality and high-substitution-degree carboxymethyl cellulose is prepared.

The present invention discloses a recombinant Escherichia coli producing nicotinamide ribokinase and a construction method and application thereof, belonging to the field of biotechnology. The present invention constructs a nicotinamide ribokinase, and its amino acid sequence is shown in SEQ ID NO.7. The present invention utilizes genetic engineering technology to construct a recombinant Escherichia coli NMN-HS01 expressing the above-mentioned nicotinamide ribokinase, and the nicotinamide ribokinase expressed by the recombinant bacteria or the whole cell of the recombinant bacteria is used for catalytic reaction, which can realize the efficient production of β-nicotinamide mononucleotide. The present invention also provides a method for producing β-nicotinamide mononucleotide, the catalytic reaction is carried out at normal temperature and pressure, and is environmentally friendly; no toxic and harmful organic solvents are used, which reduces environmental pollution; the entire catalytic process is a one-step reaction, which has the advantages of high conversion rate, concise purification steps and simple process, can better save production costs, and has broad application prospects.

The invention provides a synthesis method of saflufenacil, and belongs to the field of chemical synthesis. The preparation method comprises the following steps: reacting N-(2-chloro-4-fluoro-5-aminobenzoyl)-N '-isopropyl-N'-methyl sulfonamide serving as a raw material with chloroformate in a strong polar solvent, then directly adding alkali and ethyl 3-amino-4, 4, 4-trifluoro-2-butenoate into the reaction material, and carrying out cyclization reaction, so as to obtain the N-(2-chloro-4-fluoro-5-aminobenzoyl)-N '-isopropyl-N'-methyl sulfonamide. And carrying out methylation reaction on the cyclization reaction material and a methylation reagent to obtain saflufenacil. The selected reaction solvent is relatively single and easy to recover, so that the reaction operation is simple, the product yield is improved, and the method is suitable for industrial large-scale production and has a wide application prospect.

The invention provides a centrifugal collecting device. The centrifugal collecting device comprises a driving part and a driving part, the rotor assembly is connected with the driving piece; the liquid storage part is arranged on the rotor assembly, and the liquid storage part is provided with a liquid storage cavity; the flow guide assembly comprises a flexible flow guide pipe, and one end of the flexible flow guide pipe is connected with the liquid storage part and communicates with the liquid storage cavity; the flow adjusting part is connected with the rotor assembly, a slit is formed in the flow adjusting part, and under the condition that the flexible flow guide pipe is embedded into the slit, the flexible flow guide pipe deforms; the collection assembly comprises a treatment container, a filter part and a collection container, the filter part is arranged in the treatment container and divides the treatment container into a treatment chamber and a confluence chamber, the treatment chamber is communicated with the other end of the flexible flow guide pipe, and the confluence chamber is communicated with the collection container, that is, the effective stripping of the adsorbed secretions is realized; the dosage of a buffer solution is remarkably reduced, and the concentration of effective components in a collected solution is greatly improved, so that a detection result is closer to the content of real secretions in soil.

The application discloses lignin carbon quantum dot fluorescent bamboo fiber, a preparation method and application thereof, and relates to the technical field of bamboo fiber, in particular to a lignin carbon quantum dot fluorescent bamboo fiber, a preparation method and application thereof. The preparation method of the lignin carbon quantum dot fluorescent bamboo fiber comprises the following steps: selecting a rough planed bamboo strip sample, drying the bamboo strip sample at 80-90 DEG C until the moisture content is less than 30%, and sequentially cleaning the surface of the bamboo strip sample by using anhydrous ethanol and acetone, and then preparing the bamboo strip sample; mixing choline chloride, oxalic acid and deionized water and stirring uniformly to prepare a delignification aqueous solution; and the like. The lignin carbon quantum dot fluorescent bamboo fiber, the preparation method and the application thereof separate and treat bamboo cells, obtain bamboo fibers with high strength, use alkali lignin as a carbon source, hydrogen peroxide as an oxidant, and a small amount of p-phenylenediamine as a nucleating agent, successfully prepare lignin carbon quantum dots with yellow-green fluorescent emission by using a hydrothermal method, and combine the lignin carbon quantum dots with the bamboo fibers to prepare carbon quantum dot fluorescent bamboo fibers with fluorescent properties, and the carbon quantum dot fluorescent bamboo fibers have certain application prospects in the fields of anti-fake marks and intelligent textiles.

This invention belongs to the field of biomedical technology, specifically relating to a human stem cell factor encoding gene, a recombinant expression vector, an engineered strain, and a preparation method thereof. The nucleotide sequence of the encoding gene is shown in SEQ ID NO:1. The recombinant expression vector includes an expression vector and the encoding gene shown in SEQ ID NO:1. The engineered strain is obtained by transforming the recombinant expression vector containing the encoding gene into a host strain and screening. This invention also provides a method for preparing human stem cell factors, comprising: (1) culturing the engineered strain in a culture medium until the OD reaches a suitable range; (2) obtaining a fermentation broth through induced culture; and (3) purifying and separating the fermentation broth to obtain recombinant human stem cell factors. This invention optimizes the protein expression system and purification process while ensuring the acquisition of high-purity human stem cell factors, making it more suitable for industrial-scale production and providing a reference for achieving large-scale and efficient preparation.

The invention discloses a method for separating a mixture of benzene, cyclohexane and cyclohexene. The method includes separating a mixture containing benzene, cyclohexane and / or cyclohexene by adsorption with an adsorbent, wherein the adsorbent comprises a metal organic framework material, wherein the metal organic framework material comprises a metal ion and an organic ligand, and the organic ligand comprises 2,5-dihydroxy-1,4-benzoquinone. The method of the present invention can effectively separate a benzene-cyclohexane-cyclohexene mixture, with high separation efficiency and low energy consumption, and the organic ligands and metal salts used for preparing the metal organic framework material used in the present invention are cheap and easy to obtain, have good stability, are easy to prepare on a large scale, have high selectivity for adsorption separation, and have good industrial application prospects.

The invention discloses a near-infrared iron ion fluorescent probe as well as preparation and application thereof, and belongs to the technical field of analytical chemistry and biology. The excitation wavelength and the emission wavelength of the fluorescent probe disclosed by the invention are both located in a near-infrared region, the fluorescent probe has excellent selection performance on ferrous ions, can realize rapid detection on endogenous and exogenous ferrous ions of cells, can effectively avoid interference of autofluorescence of a sample, and improves the signal-to-noise ratio; the probe can be positioned in mitochondria, is crucial to research on the dynamic state and function of ferrous ions in the mitochondria, can rapidly image endogenous and exogenous ferrous ions in tumor cells in real time, shows a good biological fluorescence imaging application prospect, provides a powerful tool for tumor research, is beneficial to revealing the effect of the ferrous ions in tumors, and has a wide application prospect. The targeted treatment effect is evaluated, and the treatment scheme is optimized. The kit has potential clinical value in the aspects of tumor diagnosis, treatment monitoring, prognosis evaluation and the like, and has important technical effects and wide application prospects in biomedical research and clinical diagnosis.

The application discloses a preparation method and application of IgY based on a Brucella multiepitope fusion protein, the fusion protein containing 11 cell epitopes of VirB1-VirB11 and being connected in series through a flexible connecting peptide, and the amino acid sequence of the fusion protein is shown as SEQ ID NO:1; the method is to screen and connect key antigen epitopes of Brucella, construct a high-efficiency expression vector, and obtain high-affinity IgY after immunizing poultry. The IgY can significantly improve the sensitivity and specificity of Brucella detection, has a potential for passive immunotherapy, and is suitable for the fields of diagnostic reagents, drug development and livestock prevention and control.

This invention provides a method and application for transient expression of collagen in plants. The collagen fragment C3S1, C3S2, C3S3, C3S4, and C3S5 are linked together with the amino acid sequences shown in SEQ1, SEQ2, SEQ3, SEQ4, and SEQ5, respectively. This collagen fragment can be expressed using tobacco as a bioreactor. By designing expression vectors, its expression effect in tobacco can be compared, and a transient expression system in tobacco can be established to achieve efficient expression of the collagen fragment in tobacco. This preparation method can express recombinant collagen fragments in tobacco with high expression levels. Compared to full-length intron-modified collagen or expression using type I collagen, this method achieves efficient expression of type III collagen fragments in tobacco bioreactors. It has a short cycle time, requires no maintenance of cell lines and bioreactors, significantly reduces production costs, and has a high safety index.

This invention discloses a method for the direct oxidative carbonylation of methane to prepare acetic acid. Specifically, this invention provides a catalytic method for the preparation of acetic acid from methane, comprising the following steps: under solvent conditions, in the presence of light, an iron catalyst, chloride ions, and an oxidant, methane and carbon monoxide undergo a methane oxidative carbonylation reaction to obtain acetic acid. This method utilizes readily available methane, carbon monoxide, and air (or oxygen), employs an iron catalyst, and achieves direct, efficient, and highly selective acetic acid production via a one-step photocatalytic reaction, demonstrating promising application prospects. The substrate scope of this invention is broad, applicable to a range of chain and cyclic alkanes.

The invention belongs to the field of catalyst preparation, and particularly relates to a catalyst for preparing benzoquinone through aniline oxidation and a preparation method of the catalyst. In order to overcome the defects in the prior art, the invention provides a catalyst for preparing benzoquinone through aniline oxidation and a preparation method of the catalyst. According to the catalyst, manganese oxide and vanadium oxide are loaded on aluminum oxide, and metal cerium ions are introduced to improve the performance of the catalyst. Under the negative pressure environment of-1 to-1.5 kPa, the reaction temperature of 65 DEG C, the reaction time of 6 hours, the conversion rate of 100% and the selectivity of 93%, compared with the prior art, the catalyst has remarkable advantages in the process of preparing benzoquinone through aniline oxidation, the reaction rate and the product selectivity can be remarkably improved, the reaction can be performed under the condition of relatively low temperature, and the production cost and the energy consumption are reduced.

The application discloses givinostat and a synthesis method thereof, wherein compound 1 is used for synthesizing compound 2 in step 01; compound 3 is used for synthesizing compound 4 in step 02; compound 4 is used for synthesizing compound 5 in step 03; compound 5 is used for synthesizing compound 6 in step 04; and compound 6 and compound 2 are used for synthesizing givinostat in step 05. After optimization, the yield of compound 1 to compound 2 reaches more than 80 %, raw materials and reagents used in the reaction are cheap and easy to obtain, and the preparation cost is very low; only four steps are needed from compound 3 to the target product, the route is short, and the operation is simple; and after optimization, the total yield of compound 3 to the target product reaches more than 40 %, the yield is high, and the preparation cost is significantly reduced.

The invention discloses a near-infrared copper ion fluorescent probe with tumor targeting property as well as a preparation method and application of the near-infrared copper ion fluorescent probe in biological imaging, and belongs to the technical field of analytical chemistry and biology. The near-infrared copper ion fluorescent probe disclosed by the invention can efficiently detect copper ions and specifically target CXCR4 high-expression tumor cells, the near-infrared emission characteristic of the probe avoids biological autofluorescence interference, the imaging definition and sensitivity are improved, and the high selectivity and sensitivity of the probe ensure that the copper ions are accurately detected in a complex biological environment. The kit is suitable for early tumor diagnosis and research; the preparation method is simple, low in cost and suitable for large-scale production. The probe disclosed by the invention not only can monitor the change of copper ions in tumors in real time and reveal a tumor mechanism, but also has wide clinical application prospects including tumor staging, treatment monitoring and the like. The invention provides important technical support for biomedical research and clinical diagnosis.

The present invention relates to a starch branching enzyme mutant with improved extracellular secretion ability and enzyme activity. The present invention performs site-directed mutation on starch branching enzyme derived from Geobacillus thermoglucosidans, wherein the mutation sites are lysine at positions 159, 374, 393, 426 and 432, and after detecting the crude enzyme activities of the mutants, it is found that the extracellular expression of mutants K159A and K159H in Bacillus subtilis is significantly improved compared with the wild type. The crude enzyme solution is further purified using a hydrophobic column and an anion column, and the pure enzyme specific enzyme activities of mutants K159A and K159H reach 1745.18U / mg and 1873.78U / mg, respectively. The starch branching enzyme mutant provided by the present invention has improved extracellular expression ability and specific enzyme activity on the basis of the wild type, and can be applied to the modification of potato amylopectin, which is beneficial to the industrial application of starch branching enzyme.

The invention provides a method for preparing ultra-pure nano copper powder through organic copper salt reduction, and relates to the technical field of ultra-pure nano copper preparation. According to the method, supercritical carbon dioxide is used as a solvent, high-purity organic copper salt is used as a precursor, a morphology control agent without other metal ions is added, meanwhile, a water removal agent is added, and the ultra-pure nano copper powder with the diameter smaller than 100 nm can be prepared through gas reduction. The obtained ultra-pure nano copper powder is high in purity, the metal matrix purity can reach 99.997% or above, the sphericity degree is good, and the size is uniform; the method is green and environment-friendly, and the solvent is clean without residues.

The present invention provides a multispecific antigen binding protein comprising at least: (a) a first binding domain that specifically binds to a natural killer cell activated receptor (NKp46); and (b) a second binding domain that specifically binds to mesothelin (MSLN). The multispecific antigen binding protein provided by the invention can be bound with NKp46 and MSLN with high affinity, so that immune cells expressing the NKp46 are mediated to kill MSLN positive cells; and the multispecific antigen binding protein can have a full-length IgG configuration, so that the multispecific antigen binding protein has the advantages of a natural antibody in application. The invention also provides application of the multispecific antigen binding protein in tumor treatment.

The invention discloses a nucleic acid in-situ detection system based on CRISPR / dCas fusion protein and TSA signal amplification and application of the nucleic acid in-situ detection system based on CRISPR / dCas fusion protein and TSA signal amplification, and the nucleic acid in-situ detection system based on CRISPR / dCas fusion protein and TSA signal amplification comprises fusion protein based on a CRISPR / dCas system and a tyramine solution modified by a fluorophore, the fusion protein based on the CRISPR / dCas system is at least one of the following components: dCas9-HRP or biotinylated dCas9-Avi Tag, dCas9-HRP, dCas9-Avi Tag, dCas9-HRP and dCas9-Avi Wherein the dCas9-HRP has a sequence as shown in SEQ ID NO: 1 or a functional variant of the sequence as shown in SEQ ID NO: 1; the biotinylated dCas9-Avi Tag has a sequence as shown in SEQ ID NO: 2 or a functional variant of the biotinylated dCas9-Avi Tag.

The application discloses a method for preparing gamma-cyclodextrin by precipitation technology and enzyme method, and comprises the following steps: taking gamma-cyclodextrin mother liquor prepared by a solvent method and enzyme method as a sample solution; under high-temperature conditions, first, a complex formed by the gamma-cyclodextrin and a reaction aid is dissociated; then, a precipitation separation technology is used; and finally, an inorganic salt precipitant is added to effectively separate a reaction agent, so that the purification of a target product is realized, and a high-efficiency and simple gamma-cyclodextrin separation and purification method is established. By using the method, the total conversion rate of the gamma-cyclodextrin can reach about 53.89%, the recovery rate of the gamma-cyclodextrin after separation can reach 82.76% to 90.84%, the purity is 92.56% to 95.63%, and the residual amount of the reaction aid is 0.02%.

The application provides a viscosity-responsive luminescent probe, a preparation method and application. The luminescent probe has an ultra-sensitive viscosity response performance, and the viscosity response range thereof covers the viscosity change range of edible oil. After the luminescent probe is added into the edible oil, the fluorescence intensity has a high correlation with the content of the polar component in the edible oil. The change of the polar component of the edible oil is obtained by using the response of the luminescent probe to the viscosity change of the edible oil, so that the rapid and sensitive detection of the polarity of the frying oil is realized.

The application discloses a kind of metal organic framework materials and preparation method and application thereof.The metal organic framework material provided by the application includes metal ions and organic ligand, and the organic ligand is selected from the compound shown in formula I or formula II.The metal organic framework material of the application has excellent adsorption separation selectivity to p-xylene.The raw material for synthesizing the material is cheap and easy to obtain, the material preparation process is simple and low in cost, and the material has good regeneration and repetition performance, and can maintain the original adsorption effect after vacuum or heating regeneration, and has wide industrial application prospect.

The invention relates to a starch branching enzyme mutant with improved extracellular secretion ability and enzymatic activity. Site-directed mutagenesis is carried out on starch branching enzyme derived from Geobacillus thermoglucosidans, mutation sites are lysine at the 159th site, the 374th site, the 393th site, the 426th site and the 432nd site, and after the crude enzyme activity of the mutants is detected respectively, the extracellular expression quantity of the mutants K159A and K159H in bacillus subtilis is found to be obviously improved compared with that of a wild type. A hydrophobic column and an anion column are further utilized to purify the crude enzyme liquid, and the specific enzyme activities of pure enzymes of the mutants K159A and K159H respectively reach 1745.18 U / mg and 1873.78 U / mg. The extracellular expression ability and specific enzyme activity of the starch branching enzyme mutant provided by the invention are improved on the basis of a wild type, and the starch branching enzyme mutant can be applied to modification of potato amylopectin and is beneficial to industrial application of the starch branching enzyme.

The invention relates to the technical field of isatoic anhydride compounds, and discloses an isatoic anhydride compound and a preparation method thereof, and the isatoic anhydride compound comprises the following materials: 1g-2g of isatin, 1g-2g of phthalic anhydride, 0.1 g-0.5 g of a zinc chloride catalyst and 10ml-20ml of a dichloromethane solvent. According to the isatoic anhydride compound and the preparation method thereof, 1-2 g of isatin, 1-2 g of phthalic anhydride, 0.1-0.5 g of a zinc chloride catalyst and 10-20 ml of a dichloromethane solvent are weighed through a high-precision balance, it is ensured that all the raw materials are high in purity, and a reaction flask is pre-cleaned. The method has the advantages of simple operation process, low operation difficulty and safety risk, suitableness for large-scale production, selection of the catalyst and the solvent which are safer to the environment and operators, reduction of the generation of byproducts, improvement of the product purity, and reduction of environmental pollution and operation risk through selection of the solvent with low toxicity and low volatility.

The invention relates to the technical field of veterinary products, in particular to an artificially synthesized bovine rotavirus VP7-M protein mutant, a vaccine and application. According to the designed bovine rotavirus VP7-M mutant, disulfide bonds and hydrophobic hole filling mutation are introduced, five amino acid mutations are designed in an original protein amino acid sequence, and then a CHO cell line capable of stably expressing the bovine rotavirus VP7 protein mutant is constructed; the cell line can efficiently secrete and express VP7-M mutant protein, the conformation of the VP7-M mutant protein is similar to that of natural protein, the secreted and expressed VP7-M mutant protein is subjected to one-step affinity chromatography purification and prepared into the subunit vaccine, the immunogenicity of the VP7-M mutant protein is evaluated by immunizing a mouse, and animal experiment results show that the VP7-M subunit vaccine is good in safety and has good application prospects. The bovine rotavirus subunit vaccine has good immunogenicity and has a protection effect similar to or even better than that of a traditional inactivated vaccine, so that a foundation is laid for further preparation of the bovine rotavirus subunit vaccine.

The invention discloses a slow virus rapid packaging method conforming to IIT clinical quality inspection standards and application, and belongs to the technical field of biological medicine. Comprising the following steps: 1) laying 293T cells into a cell culture dish for incubation to prepare a 293T cell culture dish; 2) preparing a target plasmid and a packaging helper plasmid according to a ratio, adding the target plasmid and the packaging helper plasmid into a transfection reagent to prepare a plasmid and transfection reagent compound, adding the plasmid and transfection reagent compound into a 293T cell culture dish for culture, replacing a serum-free culture medium for continuous culture, and collecting lentivirus supernatant; and (3) centrifuging and filtering the lentivirus supernatant, adding all-purpose nuclease for incubation, then adding a PEG8000 solution, uniformly mixing, standing overnight, centrifuging, collecting lentivirus precipitate, dissolving the lentivirus precipitate by adopting a resuspension, standing, blowing away the precipitate, centrifuging, and collecting the supernatant to obtain the target lentivirus. According to the packaging method, expensive instruments or consumables are not needed, the steps are simple, operation is convenient, and a large number of slow viruses meeting the IIT level can be obtained within a short time.