36results about How to "Avoid Biosecurity Concerns" patented technology

The invention discloses a preparation method of novel renewable hydrogel with low bacterial adhesion and sterilization and regenerable functions and belongs to the technical field of hydrogel preparation. The preparation method specifically comprises steps as follows: 1) a UV polymerization reaction; 2) an esterification reaction; 3) an ATRP reaction; 4) a sliver-supporting reaction. The preparation method is simple and feasible, a polymerization method guarantees the effectiveness and controllability of the length of a functional polymer brush, and the long-time antibacterial effect is realized through slow release of silver ions. The product has a remarkable inhibition effect on escherichia coli and staphylococcus aureus; compared with an antibacterial product containing single components in the prior art, the product has greatly improved antibacterial efficiency. Besides, through the environmental responsibility of the functional polymer brush, shrinkage and extension of the polymerbrush due to the outside environment are changed, desorption of dead bacteria is further driven, and the regenerable antibacterial property of the hydrogel is realized.

The invention provides a nano-silver antibacterial fabric and a preparation method thereof. The nano-silver antibacterial fabric has the characteristics that a zinc oxide nano line grows on the fabric; and silver nano particles are deposited on the zinc oxide nano line. The zinc oxide nano line is synthesized by a solution chemical method; and the silver nano particles are deposited on the zinc oxide nano line by a simple 'immersion-illumination' method. The nano-silver antibacterial fabric prepared by the method has extremely obvious long-time antibacterial performance; the silver nano particles are small in size and cannot be accumulated; a synthesis process is environment-friendly; and the nano-silver antibacterial fabric can be recycled and reused. The nano-silver antibacterial fabric can be used for single-point water treatment to reduce microorganism content in water and can be suitable for medical surgical dressing and medical fabrics; and the nano-silver antibacterial fabric can be used as an antibacterial air filtration device for preventing bio-aerosol from being gathered on a ventilating, heating and air conditioning system.

The invention discloses a biodegradable Mg-Ca-Mn-Sn magnesium alloy material and a preparation method and application thereof. The biodegradable Mg-Ca-Mn-Sn magnesium alloy material is prepared from the following components, by mass percentage, 0.5-3% of Ca, 0.1-2% of Mn, 1-5% of Sn and the balance Mg and inevitable impurity elements brought in by raw materials. The specific preparation method includes smelting of the raw materials, casting molding, uniform annealing treatment and hot extrusion processing. The biodegradable Mg-Ca-Mn-Sn magnesium alloy has no any toxicity on human bodies and is good in mechanical performance, the preparation method is simple and low in cost, plate-shaped and rod-shaped materials in different size and cross section requirements can be prepared as required, and the biodegradable Mg-Ca-Mn-Sn magnesium alloy material can be used for preparation of bone lamellae, bone nails and other orthopedic implants, cardiovascular stents and other medical materials.

The invention discloses a biodegradable Zn-Mg-Zr alloy material. The biodegradable Zn-Mg-Zr alloy material is characterized in that the Zn-Mg-Zr alloy material comprises, by mass, 0.0001-10% of Mg, 0.0001-5% of Zr and the balance Zn. The alloy material is low in cost, nontoxic, excellent in mechanical property, low in degradation rate and excellent in biocompatibility. The invention further discloses a preparation method of the biodegradable Zn-Mg-Zr alloy material. The method is easy to implement and low in cost, plate-shaped and rod-shaped materials with different size and cross section requirements can be prepared as required, and the method can be used for preparation of bone lamellas, bone nails and other bone implantation materials as well as cardiovascular stents and other medical materials.

The invention provides a microbial sample scribing system and method and solves the problems that in the prior art the microbial sample scribing treatment is low in biosecurity, incapable of standardizing the operation, highly random in manual operation, high in human cost and low in efficiency. The microbial sample scribing system comprises a communication unit, a mechanical unit and a circuit, wherein the communication unit is in signal connection with the mechanical unit; the communication unit and the mechanical unit are respectively and electrically connected with the externally connected circuit. The microbial sample scribing system and method disclosed by the invention enable the biosecurity problem to be solved, protect the experimental environment and the operating personnel, are standardized in the operation, reduce the human cost, improve the working efficiency, standardize and mechanize the operation procedures, and increase the repeatability of the experimental result.

The invention discloses a biodegradable Mg-Ca-Mn-Sn magnesium alloy material and a preparation method and application thereof. The biodegradable Mg-Ca-Mn-Sn magnesium alloy material is prepared from the following components, by mass percentage, 0.5-3% of Ca, 0.1-2% of Mn, 1-5% of Sn and the balance Mg and inevitable impurity elements brought in by raw materials. The specific preparation method includes smelting of the raw materials, casting molding, uniform annealing treatment and hot extrusion processing. The biodegradable Mg-Ca-Mn-Sn magnesium alloy has no any toxicity on human bodies and is good in mechanical performance, the preparation method is simple and low in cost, plate-shaped and rod-shaped materials in different size and cross section requirements can be prepared as required, and the biodegradable Mg-Ca-Mn-Sn magnesium alloy material can be used for preparation of bone lamellae, bone nails and other orthopedic implants, cardiovascular stents and other medical materials.

The invention discloses a preparation method of a high-corrosion-resistance biodegradable magnesium alloy and belongs to the technical field of materials. The preparation method comprises the following steps: (1) preparing metallic magnesium, metallic zinc, metallic silver and metallic calcium as raw materials; (2) heating metallic magnesium to 760+ / -5 DEG C under the protection of N2 and SF6 mixed gas, melting, then sequentially adding metallic silver, metallic calcium and metallic zinc, stirring and uniformly mixing; (3) cooling to 740+ / -5 DEG C, introducing argon, and preserving heat and standing at 740+ / -5 DEG C for 10-20 minutes; (4) cooling to 720+ / -5 DEG C and casting; (5) heating to 300-320 DEG C and preserving the heat for 2-4 hours under the coverage of graphite powder, increasing the temperature to 350-450 DEG C, preserving heat for 8-12 hours, and cooling by water; (6) preserving the heat at 250-350 DEG C for 25-35 minutes, and then carrying out high-temperature plastic deformation; and (7) deforming at normal temperature and intermediately annealing for a plurality of times, and finally cooling by air to normal temperature. According to the method, by virtue of the single-phase fine-grain treatment, the magnesium alloy has high corrosion resistance and good mechanical property; the magnesium alloy can be used for manufacturing different implantable devices.

The invention discloses a serum-free culture medium for CHO cells. The main components include amino acids, inorganic salt components, vitamins, trace elements, yeast hydrolyzate, albumin and the like. The CHO cell serum-free medium of the present invention does not contain any serum components and animal-derived components, and its affinity is increased compared with other serum-free mediums. Cells can be directly inoculated into this serum-free medium from serum medium or other serum-free medium, and grow normally, eliminating the tedious domestication process. The invention improves the growth density and viability of CHO cells, increases the tolerance of cells in them, prolongs the maintenance time of the growth platform, and most importantly improves the ability of CHO engineered cells to express foreign proteins in them, greatly improving Product yield.

The invention relates to an antibacterial modification method of polymer materials. The antibacterial modification method comprises following steps: preparing diazomethane with a thioether group; using diazomethane to carry out chemical modification on the surface of a polymer material; and carrying out Ag-S coordination reactions between a nano silver particle solution and the chemically modifiedpolymer material. After antibacterial modification, Ag is bonded with the polymer material through chemical bonds, so during the using process, silver leakage is prevented, and the biological safetyis guaranteed.

The invention discloses a method for preparing cows with precise BLG-gene knockout by using a third-generation base editor. The method for preparing the cows with gene knockout includes the followingsteps: mutating the 277th base from the 5' end of a BLG gene in a starting cow genome into T from C, wherein the BLG gene is a DNA molecule shown in SEQ ID No. 1. A large-animal point mutation technology is established, precise single-base mutation is performed, termination codons are through exquisite design of C-T mutation so as to terminate protein translation in advance, so that the purpose ofgene knockout is achieved. Natural mutant animals are simulated, genomic double-strand break is not caused by the BE3-based point mutation technology when the method is compared with a traditional gene editing technology, and thus random mutation and even damage to the genome are avoided greatly, so that the method is safer. Important technical support is provided for researches of precise gene editing and gene knockout of cows.

The invention provides a first small molecule peptide with oxygen carrying potential, a second small molecule peptide capable of generating active oxygen, and a preparation method of the first and second small molecule peptides. The sequence of the first small molecule peptide with oxygen carrying potential of the present invention is C17H31-CONH-VRGDS-COOH. The unsaturated double bond functionalgroup in the structure can be oxidized by lipoxygenase to form a conjugated double bond and the side groups generate hydroperoxide. The method of constructing the second small molecule peptide by thefirst small molecule peptide is an enzymatic method, and the structure of the second small molecule peptide is C17H31O2-CONH-VRGDS-COOH. The method that the second small-molecule peptide generates active oxygen is a Fenton-like reaction. C17H31O2-CONH-VRGDS-COOH produces cytotoxic active oxygen under the catalysis of Fe<2+>.

The invention discloses a method for preparing CD163 gene edited pigs by using a single base editor SpRY-BE4. The invention provides gene editing for the CD163 gene of the porcine isolated fibroblast genome, so that the 228th base of the E3 exon of the biallelic CD163 is mutated from C to T, and TGA is formed after the mutation The terminator terminates the expression of the E3 exon in advance to obtain CD163 biallelic mutant cells; the nucleotide sequence of the E3 exon is sequence 2. The CD163 double-allelic knockout pig obtained by the present invention has the ability to resist PRRSV virus, indicating that the method for preparing the CD163 double-allelic knockout pig of the present invention can obtain pigs resistant to PRRSV virus.

The invention relates to a method for preparing a subcutaneous filling, in particular to a method for preparing a hyaluronic acid gel for subcutaneous filling, and belongs to the technical field of biological material preparation. In the preparation method of the present invention, the method of introducing aldehyde groups and hydrazide groups into the polymer chain is adopted to realize the effect of fine needle injection and rapid in-situ molding, and avoid the explosion caused by the high viscosity of the preformed hydrogel and the difficulty of fine needle injection. Needle issues and biosafety issues caused by small molecule crosslinker residues. Moreover, in the preparation method of the present invention, the process of modifying aldehyde sodium hyaluronate with maleoyl groups after freeze-drying is used to realize the grafting of maleoyl groups with a high degree of substitution on the molecular chain of hyaluronic acid, so that hyaluronic acid can be used in subsequent raw materials. In the process of in-situ molding, further polymerization can occur under the irradiation of ultraviolet light, which greatly improves the adhesive strength of the gel to the tissue at the injection site, and completely overcomes the problem of the gel filler moving and shifting under external force extrusion.

The invention relates to the field of biotechnology, in particular to a recombinant natrigovibrio and application thereof. The invention provides a recombinant sodium-demanding Vibrio, which expresses glycerol dehydratase, glycerol dehydratase activator and alcohol dehydrogenase, and the recombinant sodium-demanding Vibrio is comparable to wild-type sodium-demanding Vibrio have reduced expression and / or enzymatic activity of transcriptional regulators, said transcriptional regulators being arcA and / or glpR. The present invention transforms Natovibrio so that it can efficiently utilize glycerol to ferment and produce 1,3-propanediol, the yield of 1,3-Propanediol is high, the by-products are few, and the extraction and separation process is simple; The potential biosafety problems of traditional 1,3-propanediol production strains and the low tolerance of strains to salt in crude glycerol have important industrial application value.

The invention relates to a method for isolating and expanding stem cells after umbilical cord tissue resuscitation and a special culture medium thereof, including the steps of umbilical cord tissue resuscitation, tissue block acquisition, isolation of primary stem cells, and expansion and passage of stem cells. Type II Collagenase, TrypLE TM Sodium chloride injection of express and prolinephthalein amino acids, the medium used is sodium selenate, bovine transferrin, ornithine, 5-7mg / ml lectin, α-tocopheryl succinate monoester , IL‑6, LIF and HGF in DMEM / F12 medium. The isolation and culture method provided by the present invention has short crawling time of human umbilical cord mesenchymal stem cells, short culture period of primary stem cells, high purity of stem cells and good activity, and can be passed down for many times. Potential for high differentiation.

The invention discloses a biodegradable Zn-Mg-Zr alloy material. The biodegradable Zn-Mg-Zr alloy material is characterized in that the Zn-Mg-Zr alloy material comprises, by mass, 0.0001-10% of Mg, 0.0001-5% of Zr and the balance Zn. The alloy material is low in cost, nontoxic, excellent in mechanical property, low in degradation rate and excellent in biocompatibility. The invention further discloses a preparation method of the biodegradable Zn-Mg-Zr alloy material. The method is easy to implement and low in cost, plate-shaped and rod-shaped materials with different size and cross section requirements can be prepared as required, and the method can be used for preparation of bone lamellas, bone nails and other bone implantation materials as well as cardiovascular stents and other medical materials.