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

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 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 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 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.