15 results about "Salting out" patented technology

The invention discloses a high-strength microneedle with directional holes for biological analysis sampling and a preparation method of the high-strength microneedle, and belongs to the technical field of microneedles, the method comprises the following steps: filling a silk fibroin solution into a microneedle mold to form a microneedle preform, the microneedle preform comprising a needle body part and a backing part; performing directional freezing on the microneedle preform to enable ice crystals to directionally grow in the direction from the backing part to the needle body part, and demolding to obtain a frozen blank; the frozen blank is placed in an organic solution of a cross-linking agent, soaked at the low temperature lower than 0 DEG C for ice template low-temperature solvent exchange-cross-linking treatment, taken out and cleaned, then soaked in a salt solution for salting-out treatment strengthening, taken out and cleaned and freeze-dried, and the high-strength microneedle with the directional holes is obtained. The microneedle prepared through the method has high strength and excellent puncture performance, and the skin interstitial fluid collection speed and efficiency are greatly improved.

The invention provides a preparation method of a terminal-peptide-free bovine type I collagen product. The preparation method comprises the following steps: obtaining a crushed bovine tissue raw material without impurities; the preparation method comprises the following steps: soaking a cattle tissue raw material in acid, and homogenizing to obtain cattle tissue homogenate; protease is added into the bovine tissue homogenate in batches for enzymolysis, the enzymolysis temperature is controlled to be 2-6 DEG C, after salting-out precipitation, pH value adjustment and redissolution are carried out on the bovine type I collagen extracting solution obtained in the middle batch, protease is added again for enzymolysis, salting-out precipitation, pH value adjustment and redissolution are carried out again, and the bovine type I collagen extracting solution is obtained. Repeating for multiple times to obtain a terminal-peptide-free bovine type I collagen solution; adjusting the pH value of the terminal-peptide-free bovine type I collagen solution, salting out, precipitating, centrifuging and washing to obtain terminal-peptide-free bovine type I collagen precipitate; and purifying the terminal-peptide-free bovine type I collagen precipitate to obtain the terminal-peptide-free bovine type I collagen product. According to the telopeptide-free bovine type I collagen product provided by the invention, no residual telopeptide is detected, and the purity is high.

This invention discloses a method for salting out salmon PDRN. The method includes: adding a soluble salt and an organic solvent to a salmon ooze enzymatic hydrolysate, mixing thoroughly, allowing the mixture to stand and separate into three phases, forming a three-phase salting-out extraction system consisting of an upper phase, an intermediate phase, and a lower phase; collecting the intermediate phase when the organic solvent is hydrophilic, and collecting the lower phase when the organic solvent is hydrophobic; purifying and drying the collected intermediate or lower phase to obtain PDRN powder. This invention uses salmon ooze enzymatic hydrolysate as raw material and extracts salmon PDRN product in one step through salting-out extraction. The PDRN product yield is greater than 5.0%, A260 / A280 is 1.8–2.0, A260 / A230 is ≥2.0, endotoxin content is <0.03 EU / mg, protein content is ≤0.5%, and molecular weight is 200–4000 bp. The method of this invention has the advantages of simple process, low cost, high yield, and high product purity, making it suitable for large-scale industrial production.

The invention relates to the field of bioengineering, in particular to a perch collagen peptide as well as a preparation method and application thereof. The invention provides a preparation method of perch collagen, which comprises the following steps: carrying out acid extraction on pretreated perch scales, hydrolyzing with a first enzyme, filtering, salting out filtrate, centrifuging, collecting precipitate, redissolving, purifying, hydrolyzing with a second enzyme, and heating to obtain the perch collagen, enzymes adopted by the first enzyme hydrolysis and the second enzyme hydrolysis can be the same or different; the enzyme comprises one or more of alkaline protease, papain, subtilisin and pepsin. The collagen peptide extracted from sea bass scales and processed into the sea bass scales is systematically researched and developed, and the collagen peptide has an excellent anti-photoaging effect and high replicability. The collagen peptide is low in molecular weight, high in oxidation resistance and wide in application range, and can be applied to the fields of cosmetics, oral collagen supplements and the like.

The present invention relates to the technical field of medical dressing materials, and more specifically to jellyfish collagen sponges and methods for producing the same. Step S1: Adjust the concentration of a jellyfish collagen raw material with a molecular weight of 80 kDa or more with pure water to obtain a collagen solution with a mass concentration of 0.2 to 0.5%. Step S2: Add ethanol to the jellyfish collagen solution, stir, and let stand. Step S3: Obtain a precipitate by centrifugation or obtain a filter cake by suction filtration. Step S4: Freeze-dry under vacuum to obtain a collagen sponge. 60 The present invention includes step S5, which involves radiation sterilization, packaging, and storage. The collagen sponge produced by this invention has a dense structure, the collagen does not denature, it has strong liquid absorption capacity, and it is resistant to deformation and collapse even when exposed to water. The manufacturing method of this invention avoids technical problems such as the inclusion of impurities due to salting out, low pH precipitation efficiency, or low mechanical strength of the collagen sponge.

This invention provides a method for preparing androstane-3,6,17-trione (E,Z)-3-[O-(2-aminoethyl)]oxime hydrochloride, comprising the following steps: benzophenone oxime reacts with 2-chloroethylamine hydrochloride in dimethyl sulfoxide, followed by acid-base adjustment, toluene extraction, hydrolysis with concentrated hydrochloric acid to remove the protecting group, and crystallization to obtain high-purity 2-aminoethylamine hydrochloride; androstane-3,6,17-triol is used as a raw material and oxidized under the catalysis of sodium bromate and ruthenium oxide (IV), quenched, separated, washed with water, and crystallized by solvent replacement with isopropanol to obtain androstane-3,6,17-trione; the 2-aminoethylamine hydrochloride solution is mixed and reacted with the trione in tetrahydrofuran solution at low temperature, followed by salting out, filtration, separation, washing with saturated brine and drying with magnesium sulfate, and purification by solvent replacement, water dissolution and concentration, and cooling crystallization to obtain the high-purity target product. This invention significantly improves the yield of the target product by optimizing reaction conditions, while achieving readily available raw materials, low cost, and industrialized production through traditional chemical reaction pathways.

The invention relates to the technical field of bioengineering, in particular to a preparation method of stable natural creatine kinase. Comprising the following steps: removing fascia fat from a pig heart, adding a DK1 buffer solution, and crushing by a meat grinder to obtain an enzyme extracting solution A; adding ammonium sulfate into the crude enzyme extract A for multiple times, adjusting the pH value by using DK2, centrifuging, and taking supernatant to obtain an enzyme extract B; adding solid ammonium sulfate into the enzyme extracting solution B to carry out salting-out precipitation, centrifuging to take precipitate, and dialyzing with DK2 to obtain an enzyme extracting solution C; purifying through an ion exchange column, and sequentially eluting through a DK3 buffer solution to obtain a creatine kinase solution; carrying out concentration dialysis liquid change treatment on creatine kinase by using DK4 to obtain an enzyme extracting solution D; adding a liquid protective agent into the enzyme extracting solution, and carrying out stabilizer research; through the mode, high-activity and high-stability creatine kinase can be obtained, the process repeatability is high, the cost is low, and large-scale production of the process is facilitated.

This invention relates to the field of biomaterials technology, and more particularly to a protein-based tubular hydrogel, its preparation method, and its applications. The hydrogel is prepared from the following raw materials: a skin layer solution and a core layer solution; the skin layer solution comprises a 5-20 wt% aqueous protein solution; and the core layer solution comprises a 20-30 wt% aqueous hydrophilic salt solution. The hydrogel preparation steps include: mixing the skin layer solution and the core layer solution in a receiving bath via coaxial extrusion, followed by solidification to form the hydrogel. This method uses a high-concentration salt solution to induce protein salting out, constructing a tubular hydrogel structure. The addition of polysaccharides or shaping agents enhances the gel's plasticity and stability, preventing deformation and collapse. The resulting tubular material exhibits excellent biocompatibility and mechanical properties, making it suitable for biomedical scaffolds and other applications. Furthermore, the preparation process is simple and inexpensive, indicating broad prospects for industrialization.

This invention relates to the field of oil and gas drilling engineering technology, specifically to a solids-free kill fluid and its preparation method, comprising the following raw materials by weight: 80-100 parts base fluid, 25-35 parts composite additives, 8-12 parts soluble thickener, 6-10 parts liquid phase anti-collapse agent, and 3-5 parts lubricant. In this invention, a high-density system is constructed through additive A of the composite additives, breaking through the specific gravity limit of traditional salt-based weighting agents. Combined with the solubilizing and stabilizing effect of triethanolamine, high-concentration components are prevented from salting out, effectively solving the problem of limited specific gravity increase in traditional solids-free kill fluids. Simultaneously, additive B constructs a liquid-phase cross-linked colloidal network, increasing the system viscosity and forming a liquid plug, effectively blocking the exchange and dilution between the kill fluid and residual wastewater in the wellbore, preventing performance degradation of the kill fluid due to dilution, and reducing material waste caused by replenishing the kill fluid.

This invention belongs to the field of biotechnology. Specifically, it discloses a method for preparing recombinant protein using rice seeds. The method involves dehulling rice seeds to obtain rice flour, which is then enzymatically hydrolyzed using cellulase and neutral protease in a buffer solution. This process efficiently hydrolyzes the cellulose in the rice cell wall and some impurities. The buffer solution reduces protein salting out and increases the dissolution rate of recombinant human lactoferrin. Activated carbon is used to initially adsorb and remove impurities such as natural pigments and phenolic substances from the rice seeds. The mixture is then subjected to chromatography using CM Sepharose FF, SP Sepharose XL, and CM Sepharose FF columns, effectively improving the purity and recovery rate of the recombinant human lactoferrin. Simultaneously, the enzymatic hydrolysis and fractionation chromatography effectively reduce the iron saturation in the recombinant human lactoferrin.

The application discloses a method for preparing porous silica microspheres by salting-out, and belongs to the field of preparation of silica microspheres. The method comprises the following steps: preparing water glass, inorganic salt, organic solvent, emulsifier and an emulsifying machine, and preparing porous silica microspheres through an emulsification process, a salting-out process, standing separation, ripening and washing and drying. The method for preparing porous silica microspheres by salting-out greatly simplifies the process and process conditions, and makes the pore volume and pore size of the porous silica microspheres controllable.

This invention provides a method for preparing a medical-grade high-transparency collagen solution, comprising the following steps: S1. Fresh animal tissue is taken, and after removing hair, fascia, fat, and flesh, it is sliced, washed to remove blood, washed with water, and freeze-pulverized; S2. The pulverized material is soaked in a mixed defatting agent for defatting; the mixed defatting agent includes a cationic surfactant and a lipase, wherein the cationic surfactant includes at least one of a bio-based surfactant and a quaternary ammonium salt surfactant; the bio-based surfactant includes at least one of rhamnolipid, sophorolipid, and trehalose; S3. The defatted material is frozen, irradiated, then soaked in purified water, filtered, and the swollen material is collected; S4. The swollen material is enzymatically hydrolyzed; S5. The filtrate after enzymatic hydrolysis is collected, salted out, filtered, and the residue is collected, then washed in a salt solution to obtain the salted-out material; S6. The salted-out material is dissolved in pure water, and the collagen protein mass fraction is controlled at 0.01-6.5%, then ultrafiltration is performed, the filtrate is collected, and stored at low temperature to obtain a collagen solution. The collagen prepared by this method has high transparency, and its structure remains intact during the preparation process, meaning the final collagen solution retains its complete triple helix structure. Furthermore, the entire extraction process does not involve the addition of heavy metals or toxic reagents, thus eliminating the risk of heavy metal or toxic reagent residues and broadening its application range.

This invention relates to a non-targeted identification method for mycotoxin metabolites in wine based on mass spectrometry coupled with chromatography, specifically for the detection and identification of ochratoxin A and its metabolites in wine. Through sample pretreatment, chromatographic separation, mass spectrometry detection, data screening, and fragment ion confirmation of wine samples, non-targeted detection of ochratoxin A and its metabolites can be achieved without relying on standards. In the sample pretreatment stage, the target analyte is extracted using acidified acetonitrile solution, and impurities are removed by salting out and centrifugation. Separation of ochratoxin A and its metabolites is achieved by coupling high-performance liquid chromatography with time-of-flight mass spectrometry using a reversed-phase C18 column for gradient elution. The mass spectrometry analysis uses full-scan mode and alternates between positive and negative ion modes to ensure high resolution and high sensitivity, making it suitable for the detection of mycotoxins in wine and other foods, meeting food safety regulatory requirements.