28 results about "Endotoxin removal" patented technology

The invention discloses humanized III-type collagen as well as a preparation method and application thereof, and belongs to the technical field of bioengineering. According to the method, firstly, on the basis of an original humanized III-type collagen gene, cell adhesion activity is taken as an evaluation index, a better cell adhesion sequence is screened out and spliced and integrated with the original collagen gene, and brand-new humanized III-type collagen is obtained. And constructing a recombinant expression vector of the humanized III type collagen containing the adhesion sequence by taking the probiotic EcN as a host cell, and introducing the recombinant expression vector into the EcN to obtain a strain of functional recombinant probiotic. Compared with a traditional escherichia coli engineering bacterium BL21 (DE3), the recombinant probiotics have good cell adhesion activity while efficiently expressing the humanized type III collagen, the bacterial endotoxin content of the recombinant humanized type III collagen obtained through purification meets the industrial standard, and the recombinant probiotics have good application prospects. The purification cost caused by industrial removal of endotoxin can be avoided, so that the production cost is reduced, and the method has a good application prospect.

The invention discloses a high-stability endotoxin-free PHA nano-emulsion and a preparation method thereof, and belongs to the technical field of biodegradable high polymer material compositions and processing thereof. The nano-emulsion is characterized in that the endotoxin content is not higher than 0.10 EU / g, the median particle size d50 is 100-200 nm, and the PDI is not higher than 0.15, and the nano-emulsion is stable in long-term storage. The preparation method is a continuous solvent-free process and comprises the steps of melt extrusion, high-pressure thermal emulsification and deep endotoxin removal. By adopting the specific pH-insensitive cationic polymer emulsifier and the crystallization inhibitor, the chemical contradiction that an efficient alkaline purification process is incompatible with a nano-emulsion stable system is solved, physical aging is inhibited, and an unexpected technical effect is obtained. The invention also discloses an O / W type cream containing the nano emulsion.

The invention relates to the technical field of biomacromolecule separation and purification engineering, and discloses a chromatographic separation method for removing endotoxin in a vaccine preparation, which comprises the following steps: preparing an equilibrium buffer solution containing citrate with specific concentration and L-arginine hydrochloride; providing a mixed mode chromatography medium with hydrophobic and ion exchange complex ligands and balancing with a buffer; according to the method, through the synergistic effect of 8.0-12.0 mmol / L of citrate and 150-250 mmol / L of L-arginine hydrochloride, the endotoxin micelle structure is destroyed and is induced to be dissociated into monomers, and meanwhile, L-arginine is used for inhibiting monomer aggregation, so that the monomers are diffused into inner holes of the medium in a small size to be adsorbed, and the endotoxin micelle structure is separated into the medium. Therefore, the problem of separation caused by size overlapping of endotoxin micelles and antigens is solved, and double breakthrough of deep removal of endotoxin and high recovery rate of antigens is realized.

The invention belongs to the technical field of biology, and provides a pseudomonas aeruginosa endotoxin specific binding polypeptide and application thereof. The amino acid sequence of the polypeptide is shown as SEQ ID No. 1, SEQ ID No. 3 or SEQ ID No. 4 in a sequence table. Experiments prove that the polypeptide has excellent affinity with pseudomonas aeruginosa endotoxin, and compared with an existing anti-endotoxin clinical drug polymyxin B, the polypeptide has obviously better pseudomonas aeruginosa endotoxin detoxification capability. On the basis, the invention further provides application of the polypeptide in removal or separation or analysis of the endotoxin of the pseudomonas aeruginosa and application of the polypeptide in preparation of a detoxification medicine for the endotoxin of the pseudomonas aeruginosa. The polypeptide can be widely applied to the biomedical fields of biological separation, biological detection, disease diagnosis and treatment and the like.

The invention relates to the technical field of hemodialysis, in particular to a preparation method and system for a low-endotoxin hemodialysis concentrated solution, and the method comprises the steps: obtaining a preparation data set, extracting a temperature sequence, a pH value sequence and an endotoxin content index value, and calculating a membrane flux distribution sequence and an adsorbent activity distribution sequence. Performing primary dialysis path optimization to generate a first completely optimized network; identifying a target path node pair according to the target endotoxin content value, and performing secondary path extension to generate a second completely optimized network; and finally identifying a temperature and pH value regulation and control sequence corresponding to the target path node to complete preparation. By optimizing the network, the test workload is remarkably reduced, the endotoxin removal efficiency and the process parameter control precision are improved, and the problems that in the prior art, the endotoxin removal efficiency is low, and the product batch stability is poor are solved.

The present application relates to a method for removing endotoxin from alginate oligosaccharide and alginate oligosaccharide with endotoxin removed, aiming to provide a method for efficiently removing endotoxin from alginate oligosaccharide with simple operation and easy industrialization. The technical points are: insoluble particles are removed by centrifugation, mixed Lewis acid is added for synergistic treatment, the treated solution is acidified to form a precipitate, the precipitate is washed with deionized water, an alkaline solution is added to dissolve the precipitate and filter, the filtrate is adsorbed by an adsorption medium, then alginate oligosaccharide is eluted with an organic solvent, and the alginate oligosaccharide with endotoxin removed is obtained after drying. The present application removes endotoxin from alginate oligosaccharide by using mixed Lewis acid synergistic treatment and adsorption by an adsorbent, no impurities are introduced during the preparation process, the endotoxin content in the obtained alginate oligosaccharide is low, the operation is simple, and the preparation process is suitable for industrial production.

This invention discloses a highly stable, endotoxin-free PHA nanoemulsion and its preparation method, belonging to the field of biodegradable polymer material compositions and their processing technology. This nanoemulsion has an endotoxin content of no more than 0.10 EU / g and a median particle size of d... 50 Characterized by a nanoparticle size of 100-200 nm and a PDI not exceeding 0.15, it exhibits long-term storage stability. Its preparation method is a continuous solvent-free process, including melt extrusion, high-pressure thermal emulsification, and deep endotoxin removal steps. This invention resolves the chemical incompatibility between efficient alkaline purification processes and the stable nanoemulsion system by employing specific pH-insensitive cationic polymer emulsifiers and crystallization inhibitors, and also inhibits physical aging, achieving unexpected technical effects. This invention also discloses an O / W type cream containing this nanoemulsion.

The invention discloses a salmonella bacteriophage Y1 with a wide lysis spectrum and a preparation method of a low-endotoxin preparation of the salmonella bacteriophage Y1. The preservation number of the salmonella bacteriophage Y1 is CCTCC M 20242911. The method comprises the following steps: adding a chitosan solution into a bacteriophage suspension, uniformly mixing, and precipitating overnight at room temperature. The salmonella phage Y1 disclosed by the invention is high in cracking capacity and can be applied to preparation of drugs for preventing and treating salmonella. The method disclosed by the invention is low in cost, simple in used equipment, simple and convenient in operation procedure, stable in effect, easy for large-scale industrial production, low in endotoxin preparation 3, good in endotoxin removal effect and small in influence on the activity of the bacteriophage.

The invention discloses a method for removing endotoxin in chicken infectious bursal disease virus VP2 protein. The method comprises the following steps: firstly, crushing a VP2 protein expression strain; adding calcium chloride into the treated VP2 protein, and standing; returning the temperature, adding sodium carbonate into the VP2 protein subjected to temperature returning, and standing; and returning the temperature of the VP2 protein added with the sodium carbonate, taking supernate, adding calcium chloride into the supernate, and standing. By setting the adding concentration of calcium chloride, the adding concentration of sodium carbonate and the treatment sequence and times of calcium chloride and sodium carbonate, the endotoxin in the VP2 protein is efficiently and rapidly removed by using calcium chloride and sodium carbonate. By adopting the method disclosed by the invention, the endotoxin removal rate reaches 99.91%, the agar diffusion titer is improved compared with that before treatment, and the animal vaccine preparation standard is met. The method disclosed by the invention is short in treatment period, large in treatment capacity, low in removal cost and suitable for industrial mass production.

The utility model discloses an endotoxin removing device. The endotoxin removing device comprises a tank body and an endotoxin removing assembly, the endotoxin removal assembly is mounted in the tank body and is used for removing endotoxin in pure steam formed by heating and evaporating raw water; the endotoxin removing assembly comprises a first shell, a second shell and a filter screen; the corresponding end parts of the first shell and the second shell are connected to form a frame structure; the filter screens are installed on the two sides of the frame structure, and the filter screens and the frame structure form a hollow frame structure. The frame structure is filled with a silk screen. According to the device, endotoxin in pure steam can be removed, and the purity of the pure steam is improved.

The invention relates to the technical field of biology, in particular to a method for removing bacteriophage endotoxin, which comprises the following steps: step 1, selecting ion exchange resin as an adsorption material; step 2, removal pretreatment: putting ion exchange resin into a chromatographic column, and washing and soaking the ion exchange resin in the chromatographic column with a 0.5-1M sodium hydroxide standard solution; and step three, removing endotoxin from the bacteriophage: adjusting the pH value of the ion exchange resin to 7.2-7.4, adding the bacteriophage of which the endotoxin is to be removed into the chromatographic column, and standing for 10-15 minutes. According to the method, the ion exchange resin is used as an adsorption material and is loaded into the chromatographic column to remove the phage endotoxin, other equipment is not needed, and the operation is simple; the ion exchange resin is high in durability and stability and can be repeatedly used and stably stored, so that the cost is reduced; meanwhile, the removal process is efficient and rapid.

The present invention discloses a nanomagnetic bead for removing endotoxins from protein samples, as well as a preparation method and application thereof. The nanomagnetic bead comprises an inner core, an intermediate layer, and an outer layer; the inner core is a magnetic core, the intermediate layer is a metal oxide layer, and the outer layer is a boronic acid ligand layer. The metal oxide layer coordinates with the phosphate group in the endotoxin, and the boronic acid ligand layer combines with the cis-diphenol structure in the endotoxin. The nanomagnetic beads of the present invention achieve an endotoxin-clearing effect through a dual mechanism. The nanomagnetic beads for removing endotoxins from protein samples of the present invention can reduce the endotoxin content in the protein to below 0.5 EU / mL, meet the raw material requirements in the pharmaceutical field, and the protein will not be denatured. It has the advantages of simple and rapid operation, low cost, high endotoxin removal rate, and high protein recovery rate.

The invention relates to a method for early-stage removal of endotoxin in plasmid DNA preparation. The method comprises the following steps: (1) carrying out microfiltration on a lysis neutralization solution to obtain a filtrate; (2) concentrating the filtrate to obtain a concentrated solution, exchanging the obtained concentrated solution with purified water or a 10 * TE buffer solution, and adjusting the pH value to 4.4-5.6 with acetic acid to obtain an acidic solution; (3) adding zinc sulfate with the final concentration of 0.5-1M into the acidic solution, and incubating at 10-20 DEG C for 20-60 minutes to obtain an incubation solution; and (4) carrying out microfiltration on the incubation liquid, and carrying out ultrafiltration replacement on the obtained filtrate to remove the precipitate. The early clearing method for endotoxin in plasmid DNA preparation is efficient, economical and safe, endotoxin pollution can be controlled from the source, the proportion and yield of superhelix plasmids are considered, and the quality of plasmid DNA is improved. The early clearing method for endotoxin in plasmid DNA preparation can simplify the downstream purification process, and is especially suitable for large-scale industrial production of high-quality plasmid DNA.

The present invention discloses a PES membrane modification method, a PES membrane, and its application in endotoxin removal. The modification method, based on membrane surface treatment and chemical modification, significantly increases the number of amino groups on the PES membrane surface through a Schiff base / Michael addition reaction, thereby increasing the positive surface charge of the PES membrane. The method offers advantages such as high efficiency and energy saving, ease of operation, easy process control, and ease of scale-up and integration. The modified PES membrane positively modifies the original PES membrane surface, significantly increasing its positive surface charge, enabling electrostatic adsorption to remove endotoxins present in intravenous medications. Furthermore, the modified membrane introduces a large number of amino or hydroxyl groups, which readily bind to lipopolysaccharide molecules, onto the surface. These groups can be used to immobilize endotoxins on the membrane surface through molecular forces for removal, thereby ensuring that the modified membrane can remove endotoxins over a wider pH range.

A method for depletion or removal of endotoxins from a known or suspected endotoxin-containing source by virtue of a solid phase extraction material in an essentially aqueous system comprising the steps of—providing a known or suspected endotoxin-containing source, —contacting the known or suspected endotoxin-containing source with a positively charged solid phase material having a surface on which ferric iron is immobilised, wherein the solid phase extraction material has immobilised the ferric iron by (2-aminoethyl)amine (TREN) ligand—incubating the known or suspected endotoxin-containing source for a period of time sufficient to bind endotoxin to the porous solid phase material, —separating the solid phase material from the essentially aqueous system, —optionally isolating the essentially aqueous system freed or depleted from endotoxin.

The present invention relates to the field of protein purification. In particular, the invention concerns methods for increasing the filtration capacity of virus filters, by combined use of endotoxin removal and cation-exchange media in the prefiltration process.

The application discloses a method for removing endotoxin in pullulan and application thereof, and mainly comprises the following steps: crude pullulan extract is precipitated and washed by an organic solvent to obtain pullulan; after being dissolved, a surfactant is added into the solution to make endotoxin aggregates depolymerize into monomolecular form; then, the solution is filtered through an ultrafiltration membrane to remove endotoxin and residual small molecular impurities and inorganic salts; finally, the polysaccharide solution is precipitated by ethanol, dried and crushed to obtain refined pullulan; the endotoxin removal method adopted by the prepared pullulan has little influence on the molecular weight of the pullulan, the endotoxin content of the obtained pullulan is not higher than 0.05 EU / mg, the prepared pullulan meets the medical standard, has high biological safety, the operation steps are simple, the pullulan is easy to realize large-scale production, and the pullulan has the advantages of rapidness, simplicity, low cost and industrialization; and the technical scheme of the application is favorable to promoting the application of the pullulan in the field of tissue engineering.

The invention relates to the technical field of aquaculture, in particular to a preparation method of a phage compound preparation of Chinese softshell turtles. The method comprises the following steps: S1, respectively separating bacillus cereus, vibrio parahaemolyticus and aeromonas hydrophila from soft-shelled turtle bodies suffering from head shaking disease, nail rot disease and hemorrhagic disease, and mixing to prepare a multi-host bacterial suspension, mixing the multi-host bacterium suspension with an environmental bacteriophage sample, performing enrichment induction, screening out a target bacteriophage, and performing purification culture to obtain a bacteriophage proliferation solution; s2, purifying the bacteriophage proliferation liquid to remove endotoxin to obtain a high-purity bacteriophage solution; and S3, preparing the high-purity bacteriophage liquid and the embedding material into the micro-capsule oral preparation through an electrostatic spraying device. The preparation method comprises the following steps: directionally screening high-cracking bacteriophages aiming at main pathogenic bacteria of soft-shelled turtles, constructing a bacteriophage combination, preparing a targeted microcapsule preparation by combining an electrostatic spraying technology through a constructed composite embedding structure, and cooperating with a bacteriophage synergist, so that spectral antibiosis can be realized, and the stability of the preparation is improved.

The application provides a skull flap endotoxin removal device and method, which comprises a vacuum heating device and a moisture-proof device connected with the vacuum heating device. The vacuum heating device comprises a tank body, a tank cover, a locking assembly and a heating assembly arranged in the tank body. The tank cover is connected with a vacuum device through a pipeline. The tank body and the cover are detachably connected through the locking assembly. The heating assembly is arranged in the tank body and located at a middle position. The heating assembly comprises a support column and a plurality of heating discs arranged on the support column in sequence from top to bottom. Heating wires are arranged in the support column and the heating discs. The moisture-proof device is communicated with the tank body and used for removing residual steam in the tank body after vacuum drying. The application is mainly used for physically removing endotoxin in the skull flap and has the advantages of convenient use and convenient endotoxin removal. Meanwhile, the application can avoid the situation of cooling and moisture return.

The present invention relates to a process for purifying nucleic acids, particularly plasmid DNA, from a liquid sample, which contains endotoxins in addition to nucleic acids. The invention involves a process for purifying nucleic acids from a biological sample containing nucleic acids, preferably plasmid DNA, comprising the following steps: a) providing a liquid sample comprising nucleic acids and endotoxins; b) precipitating the nucleic acids and the endotoxins or binding the nucleic acids and the endotoxins on a solid carrier and thereby separating them from the remaining components of the liquid sample; c) optionally washing the precipitate or solid carrier from step b) at least once to further remove remaining components; d) treating the nucleic acids and endotoxins separated in step b), optionally after washing in step c), using a purifying buffer for at least partial removal of the endotoxin; e) optionally washing the precipitate or the solid carrier in step d) at least once with at least one washing composition, and f) optionally collecting the nucleic acids, optionally by eluting from the solid carrier or dissolving the precipitated nucleic acid; wherein the purifying buffer in step d) comprises an amino compound selected from the group consisting of triethylamine, triethanolamine, 2-[Bis(2-hydroxyethyl)amino]-2-(hydroxymethyl)propane-1,3-diol, 1,3-bis[tris(hydroxymethyl)methvlamino]propane, 2-amino-2-(hydroxymethyl)-propane-1,3-diol, and individual salts thereof, said amino compound having a total concentration in the range of 1.1 to 5.0 mol / L, an alcohol capable of dissolving the amino compound in a total amount of 30 to 70 % by weight based on the total weight of the purifying buffer, and water, wherein the purifying buffer has a pH in the range from 3.0 to 8.0.

A method for purifying a sodium alginate powder from endotoxins and endogenous pyrogens is provided. The sodium alginate powder is thermally treated at a temperature selected based on the viscosity of the sodium alginate powder. A suspension is prepared by adding an organic solvent to the sodium alginate powder, whereafter the suspension is mechanically stirred until homogeneous. The organic solvent comprises a mixture of hexane and isopropyl alcohol in a ratio of 0.5:1-2:1. When particles of the sodium alginate powder are sedimented, a liquid dispersed medium is removed from the suspension. The particles of the sodium alginate powder are dried, and a sodium alginate solution is prepared by dissolving the dried particles in pure water. A silver-impregnated activated carbon powder containing 0.01-0.4 wt % silver is added to the sodium alginate solution. The sodium alginate solution is purified by using ultrafiltration first and then lyophilization or spray drying.

The invention belongs to the technical field of biology, and provides a salmonella typhimurium endotoxin specific binding polypeptide and application thereof. The amino acid sequence of the polypeptide is selected from any one of SEQ ID No.1 to SEQ ID No.5 in a sequence list. Experiments prove that the polypeptide can be specifically bound with the salmonella typhimurium endotoxin, and compared with an existing anti-endotoxin clinical drug polymyxin B, the polypeptide has obviously higher specific binding capacity with the salmonella typhimurium endotoxin and also has obviously better salmonella typhimurium endotoxin detoxification capacity. On the basis, the invention also provides application of the polypeptide in removal, separation or analysis of salmonella typhimurium endotoxin and preparation of salmonella typhimurium endotoxin detoxification drugs. The polypeptide can be applied to the biomedical fields of biological separation, biological detection, disease diagnosis and treatment and the like.

The invention discloses a multifunctional flea salivary protein FS58, a preparation method and application thereof in preparation of drugs for treating psoriasis, and belongs to the technical field of biological medicines. The invention provides a multifunctional protein FS58. The amino acid sequence of the multifunctional protein FS58 is as shown in SEQ ID NO. 2. The invention also provides a preparation method, which comprises the following steps: 1, gene synthesis; 2, plasmid construction and amplification; 3, recombinant expression; carrying out 4Ni < + > column affinity chromatography purification; 5, carrying out enzyme digestion and separation on the FS58 fusion protein; 6, carrying out Superdex 75 gel purification; and 7, removing endotoxin. The invention further provides application of the protein FS58 in preparation of drugs for treating psoriasis. The preparation method provided by the invention provides a way and means for efficiently and massively producing FS58. Meanwhile, the FS58 protein disclosed by the invention has the functions of inhibiting angiogenesis, resisting inflammation and regulating immunity in vivo and in vitro, and a new way and means are provided for treating psoriasis.

The invention provides a purification method for efficiently extracting plasmid DNA and removing endotoxin based on color indication. According to the method for extracting the transfection-level plasmid from the gram-negative bacteria, the transfection-level plasmid can be extracted from the gram-negative bacteria by using the first reagent to the fifth reagent, the plasmid extraction quality and yield are high, and endotoxin can be effectively removed; in addition, the extraction reagent provided by the invention further comprises an acid-base indicator, the accuracy of plasmid extraction can be determined by observing color change with naked eyes, and the extraction reagent has a color guidance function.

The present invention relates to a process for purifying nucleic acids, particularly plasmid DNA, from a liquid sample, which contains endotoxins in addition to nucleic acids. The invention involves a process for purifying nucleic acids from a biological sample containing nucleic acids, preferably plasmid DNA, comprising the following steps: a) providing a liquid sample comprising nucleic acids and endotoxins; b) precipitating the nucleic acids and the endotoxins or binding the nucleic acids and the endotoxins on a solid carrier and thereby separating them from the remaining components of the liquid sample; c) washing the precipitate or solid carrier from step b) at least once with a washing buffer comprising an alcohol to further remove remaining components; d) treating the nucleic acids and endotoxins separated in step b), and washed in step c), using a purifying buffer for at least partial removal of the endotoxin; e) optionally washing the precipitate or the solid carrier in step d) at least once with at least one washing composition, and f) optionally collecting the nucleic acids, optionally by eluting from the solid carrier or dissolving the precipitated nucleic acid; wherein the purifying buffer in step d) comprises an amino compound selected from the group consisting of triethylamine, triethanolamine, 2-[Bis(2-hydroxyethyl)amino]-2-(hydroxymethyl)propane-1,3-diol, 1,3-bis[tris(hydroxymethyl)methvlamino]propane, 2-amino-2-(hydroxymethyl)-propane-1,3-diol, and individual salts thereof, an alcohol capable of dissolving the amino compound in a total amount of 30 to 70 % by weight based on the total weight of the purifying buffer, and water, wherein the purifying buffer has a pH in the range from 3.0 to 8.0.

The invention relates to the field of biology, and discloses an apple pollen transgenic method mediated by a ferroferric oxide nano magnetic transformation system. According to the method, plasmids with endotoxin removed form a compound (MNPs-DNA) under the action of ferroferric oxide nano magnetic particles, the DNA is transferred into apple pollen through MNPs under the action of an external magnetic field of 0.1-0.5 T, transgenic seeds are obtained through artificial pollination, and transgenic fruits are obtained. The method has the advantages that a tissue culture process is not needed, the period from transgenosis to germplasm material obtaining is shortened, receptor materials are not limited by genotypes, the source is wide, operation is convenient and fast, large-scale field operation is facilitated, and the method is expected to become a platform technology to be widely applied to transgenosis cultivation of other flowering plants.

The invention discloses a preparation method of a hypoallergenic acellular matrix implant, and belongs to the technical field of biomedical materials. The preparation method comprises the following steps: swelling animal soft tissues in an alkaline solution for a short time, quickly freezing and crushing; placing the crushed sample in a hypertonic-hypotonic solution system, and performing efficient and mild decellularization treatment through circulating oscillation; then, endotoxin and other sensitizers are specifically removed by adopting a chromatography technology in sequence, denatured protein is washed by utilizing a salt solution, and finally, purification is performed through ultrafiltration or dialysis. According to the method, cell debris, nucleic acid and endotoxin can be deeply removed through multi-step synergy and combination of hypertonic-hypotonic circulating decellularization and chromatographic purification, the immunogenicity of an implant is remarkably reduced, and the natural three-dimensional structure and biological activity of an extracellular matrix are reserved to the maximum extent. The implant prepared by the method has the characteristics of low DNA residual quantity, extremely low endotoxin content and excellent biocompatibility, and is suitable for soft tissue repair and regeneration.

The invention relates to a method for removing toxin in matrigel, and belongs to the technical field of biological medicine. The method for removing toxins in matrigel comprises the following steps: S1, dissolving matrigel in a urea solution; oscillating and mixing at room temperature; s2, under the condition of room temperature, mixing the matrigel in the step S1 with an endotoxin-removing affinity filler, oscillating and mixing to enable the filler to specifically adsorb endotoxin; s3, filtering the mixture in the step S2 at room temperature, and collecting filtrate; and S4, dialyzing the filtrate in the step S3 by using a cell culture medium at 0-4 DEG C, and removing urea to obtain the matrigel. The invention finds that the matrigel is dissolved in the urea solution to enhance the solubility of the matrigel, so that the matrigel can be always kept in a liquid state in a room temperature environment, the effective contact between the matrigel and the endotoxin removal affinity filler is improved, and the matrigel is always kept in the liquid state in the subsequent treatment process to improve the endotoxin removal efficiency.