18results about How to "Avoid toxicity" patented technology

The invention provides an X-ray composite radiation shielding material and a preparation method and application thereof, and belongs to the technical field of radiation protection. The photoelectric effect and the scattering effect of X-rays in the material are remarkably enhanced by using high atomic number elements contained in the metal oxide, so that the transmittance of the X-rays is effectively reduced. Meanwhile, the oxide material has good chemical stability and environmental friendliness, and the toxicity and aging problems caused by a traditional lead-based shielding material can be avoided. The prepared composite radiation shielding material has the advantages of being low in cost, light in weight, easy to process, good in flexibility, non-toxic, environmentally friendly and the like, the shielding efficiency of an X-ray shielding coating reaches up to 70% or above when the X-ray photon energy is 70 kV or below, and the generated secondary reflectance can be reduced by 35-80% compared with lead.

This invention relates to the field of artificial bear bile powder technology, specifically to a highly efficient cloning and temperature-inducible expression vector for the 7αβ-hydroxysteroid dehydrogenase gene and its construction method. The expression vector is formed by integrating the hydroxysteroid dehydrogenase gene into the pBV220 plasmid; the hydroxysteroid dehydrogenase gene is either the 7α-hydroxysteroid dehydrogenase gene or the 7β-hydroxysteroid dehydrogenase gene. The construction of this expression vector makes it possible to obtain the protease through induced fermentation using a temperature-inducible expression system, avoiding the introduction of toxic inducers and simplifying the process. During vector construction, the target gene and the linear plasmid ligate spontaneously within the engineered bacteria, independent of endonucleases and ligases, further reducing costs and process complexity. This technical solution can solve the technical problem of toxic residues in the engineered bacterial expression products of hydroxysteroid dehydrogenase in existing technologies, and has ideal prospects for widespread application.

This invention belongs to the field of new energy and hydrogen energy, and specifically relates to an integrated energy vessel, the "Dongfang Heping," for direct seawater hydrogen production, storage, and conversion. The integrated energy vessel of this invention includes a powered platform, on which are installed a wave energy system, a photovoltaic system, a wind power system, a seawater desalination direct electrolysis hydrogen production system, a green methanol synthesis system, a green ammonia synthesis system, and a power system. The wave energy system, photovoltaic system, and wind power system are used to extract energy from the ocean and convert it into electrical energy to provide power to the powered platform, the seawater desalination direct electrolysis hydrogen production system, the green methanol synthesis system, and the green ammonia synthesis system. The power system drives the powered platform, and the seawater desalination direct electrolysis hydrogen production system, the green methanol synthesis system, and the green ammonia synthesis system are electrically connected to the power system. This invention provides a comprehensive energy ship system that integrates multiple renewable energy sources such as photovoltaic, wind power, and wave energy. It constructs a power platform at sea that integrates the production, storage, transportation, and utilization of "oceanic green hydrogen," forming an integrated energy production and conversion model of "green electricity-green hydrogen-green ammonia and alcohol." This not only meets the shipping industry's demand for green fuels but also effectively solves the problem of renewable energy consumption, promoting the deep integration of transportation and energy.

The invention relates to a mitochondrial delivery system and a preparation method and application thereof. According to the mitochondrial delivery system, safe and efficient cell entry of active mitochondria can be achieved, the mitochondrial delivery system has appropriate particle size and surface potential, toxicity to cells is avoided while the entrapment rate of the mitochondria is effectively improved and the electrochemical stability and biological activity of a mitochondrial membrane are guaranteed, and the mitochondrial cell entry efficiency is remarkably improved. The mitochondrial delivery system not only can transplant active mitochondria into common cells to repair cell damage, but also can transplant the active mitochondria into egg cells to play a role across a zona pellucida and a plasma membrane barrier. The mitochondrial delivery system can be used for treating mitochondrial diseases related to mitochondrial dysfunction, especially infertility caused by mitochondrial dysfunction of egg cells.

The invention relates to the technical field of gene engineering, and particularly provides a regulation and control system for degrading uric acid to reduce the uric acid level and application thereof.The system comprises a first functional gene, a second functional gene and a third functional gene, and the first functional gene encodes a first functional protein capable of degrading the uric acid; the first functional protein comprises one or more sequences as shown in SEQ ID NO: 1-10 or having at least 85% identity with the first functional protein; a second functional gene encoding a second functional protein capable of transporting uric acid, the second functional protein comprising one or more sequences as shown in SEQ ID NO: 11-15 or having at least 85% identity therewith; the first promoter is used for regulating and controlling the expression of the first functional gene and / or the second functional gene; the first terminator is used for terminating the expression of the first functional gene and / or the second functional gene. The regulation and control system for degrading the uric acid to reduce the uric acid level, provided by the embodiment of the invention, shows an efficient uric acid degradation function.

The application discloses an exosome preparation for treating hypofunction of ovary and a preparation method and application thereof, and belongs to the technical field of biological medicine, and particularly relates to a preparation method of an exosome preparation for treating hypofunction of ovary, which comprises the following steps: taking perinatal stem cells, subculturing, obtaining domesticated perinatal stem cells, digesting, expanding and culturing to a density of 80%-85%, adding a culture medium for culturing, collecting supernatant, collecting supernatant for 3 times, combining, filtering through a 0.45 mu m PES filter membrane first, and then concentrating to obtain a concentrated solution; centrifuging, resuspending a precipitate, purifying through a density gradient, obtaining an exosome precipitate, and suspending the exosome precipitate in a cryopreservation protective solution to obtain the exosome preparation. The application provides the exosome preparation for treating hypofunction of ovary and the preparation method and application thereof, a safe, sufficient, high-purity and stable exosome preparation is prepared, and the stem cell exosome for treating hypofunction of ovary is provided.

The invention belongs to the technical field of 3D printing, and particularly relates to a preparation method of non-isocyanate type light-cured resin.The preparation method comprises the steps that cyclic carbonate and aliphatic primary amine react in nitrogen, and a polyurethane prepolymer is obtained through vacuum drying; the preparation method comprises the following steps: reacting a polyurethane prepolymer with a chain extender in the presence of dibutyltin dilaurate and nitrogen, and carrying out vacuum drying to obtain an intermediate product A; the preparation method comprises the following steps: reacting a methacrylate monomer with a curing agent in the presence of a catalyst a and nitrogen until an amine titration end point to obtain an intermediate product B; reacting A with B to obtain non-isocyanate type polyurethane acrylate C; and uniformly stirring the non-isocyanate type urethane acrylate C, a photoinitiator and a polymerization inhibitor to obtain liquid non-isocyanate type light-cured resin D. The preparation method comprises the following steps: uniformly stirring the non-isocyanate type urethane acrylate C, the photoinitiator and the polymerization inhibitor; a non-isocyanate synthesis system is adopted, toxicity and volatility of traditional isocyanate are avoided, and the production process is safer and more environmentally friendly; and multiple production requirements on mechanical reliability, curing efficiency and safety of the material in a 3D printing use scene are met.

The application discloses a preparation method and application of a peptide self-assembled photo-induced thermoelectric composite functional film, and belongs to the field of new biological materials. The method comprises the following steps: adding a peptide and tyrosinase into a reaction system to obtain a reaction solution, the peptide comprises at least one tyrosine residue, and simultaneously comprises at least one positive electric amino acid residue and at least one negative electric amino acid residue; the tyrosinase catalyzes the reaction of the tyrosine residue in the peptide to generate a melanin-like structure, so as to self-assemble to form a photo-induced thermoelectric composite functional film at a gas-liquid interface. In the assembling process, the catalytic oxidation of the tyrosinase is simultaneously completed to prepare the film, the film is only composed of the peptide, does not need a substrate, can independently exist and can be processed into a specific shape; the melanin-like structure in the film simultaneously has photo-thermal and photo-electric dual functions, is used for tumor photo-thermal treatment and photo-electric nerve stimulation, and overcomes the problems of limited form, single function and insufficient biocompatibility of the existing peptide materials.

This invention relates to the field of rare earth allicin complex technology, and particularly to a rare earth allicin complex, its preparation method, and its application. The method includes the following steps: dissolving a rare earth nitrate in a mixed solvent of water and acetonitrile to obtain a rare earth nitrate solution; dissolving allicin in ethanol to obtain an allicin solution; adjusting the pH of the rare earth nitrate solution; adding a surfactant and auxiliary ligand to the rare earth nitrate solution to obtain a first reaction solution; slowly adding the allicin solution dropwise to the first reaction solution; heating and stirring; collecting the precipitate by vacuum distillation to obtain a crude product; washing the crude product; and purifying it by column chromatography to obtain the rare earth allicin complex. This invention, using the above-mentioned rare earth allicin complex, its preparation method, and its application, significantly increases the thermal decomposition temperature of allicin. The redox bactericidal effect of rare earth ions synergistically combines with the broad-spectrum antibacterial activity of allicin, resulting in the rare earth allicin complex exhibiting excellent antibacterial effects.

The present invention provides a chimeric cytokine receptor (CCR) comprising: (i) an exodomain which binds to a ligand selected from a tumour secreted factor, a chemokine and a cell-surface antigen; and (ii) a cytokine receptor endodomain.

The application discloses a self-hydrogen-supplying chalcone photoinitiator and application thereof in preparation of white photosensitive ink, wherein the structural general formula of the self-hydrogen-supplying chalcone photoinitiator is shown in the following formula: The self-hydrogen-supplying chalcone photoinitiator has strong absorption in the ultraviolet to visible light region, and has the characteristics of photobleaching and self-hydrogen supply. When the self-hydrogen-supplying chalcone photoinitiator is applied to preparation of the white photosensitive ink, a thick film with high reflectivity, no yellowing and excellent curing effect can be obtained. The photoinitiator has high initiation efficiency, small dosage, simple synthesis and is suitable for industrial production. The product can be used in LED and miniLED backlight structures with high reflectivity requirements.

The invention provides conductive hydrogel based on Schiff base crosslinking and tannic acid green rGO as well as a preparation method and application of the conductive hydrogel, and belongs to the technical field of biomedical materials. The preparation method of the conductive hydrogel comprises the following steps: reducing graphene oxide by using tannic acid to prepare TA-rGO; uniformly dispersing the TA-rGO in water, so as to obtain a TA-rGO dispersion liquid; adding carboxymethyl chitosan into the TA-rGO dispersion liquid to obtain a mixed liquid; and adding an oxidized hyaluronic acid aqueous solution into the mixed solution under a stirring condition, uniformly mixing, and standing to obtain the conductive hydrogel. An integrated three-dimensional network structure is cooperatively constructed through dynamic covalent Schiff base crosslinking and multiple non-covalent interaction, the material is endowed with high conductive stability, excellent mechanical toughness, self-repairing capacity, antibacterial / antioxidant activity and good biocompatibility, and it is achieved that the material is combined with electrical stimulation to accelerate healing of diabetic wounds.

The application discloses a self-derived protein anticoagulant coating and a preparation method and application thereof. The coating utilizes the oxidation of hydrogen peroxide generated by the reaction of an oxidizing agent or a reducing agent with oxygen in the air, is based on the endogenous active center (such as hematin) removal mechanism of self-extracted proteins (such as hemoglobin), induces the oxidative self-assembly of the proteins, and loads an anticoagulant in the assembly process to form a protein-anticoagulant composite nanofilm. The application utilizes the self-proteins to avoid the transmission risk of pathogens such as HIV, PERVs and prions from the source; the preparation method is simple and rapid, and the obtained coating has excellent adhesion stability, good biocompatibility and anti-biofouling capacity on the surface of various substrates. In-vitro and in-vivo experiments prove that the coating has superior anticoagulant performance, reduces the risk of bleeding and liver and kidney toxicity, and can be used for the surface modification of blood-contacting medical devices such as a heart stent, an artificial blood vessel, a central venous catheter and an extracorporeal oxygenator.

This invention provides a reactive oxygen species (ROS)-activated nitrogen mustard prodrug, its preparation method, and its application. This invention belongs to the field of medicinal chemistry. By introducing ROS-sensitive groups into nitrogen mustard compounds, it maintains an inactive state in normal tissues, only becoming activated in the tumor microenvironment due to elevated ROS levels, releasing cytotoxic nitrogen mustard components. This ROS-activated nitrogen mustard prodrug not only overcomes the shortcomings of traditional nitrogen mustard drugs but also provides new directions and ideas for the development of antitumor drugs. Furthermore, this nitrogen mustard prodrug enriches the structural types of nitrogen mustard prodrugs, improves drug selectivity in tumor cells, and reduces toxic side effects.

The utility model relates to waste heat power generation water treatment technical field, and disclose a kind of waste heat power generation circulating cooling water treatment system, electric pulse scale inhibition system is equipped with two groups and is respectively installed on processing pipe A and processing pipe B, adopts the technology that electromagnetic pulse and ultrasonic wave are combined, the attachment of scale formation in pipeline is prevented by generating electromagnetic pulse and ultrasonic wave vibration;Filtering mechanism is equipped with two groups and is respectively installed in the back of each electric pulse scale inhibition system and is used to filter and remove scale impurities in water body;Ultraviolet sterilization tank is equipped with two groups, one group of ultraviolet sterilization tank is installed between the filtering mechanism of front side and processing pipe B, another group of ultraviolet sterilization tank is installed in the back of the filtering mechanism of back side. Adopt pure physical processing mode, by electric pulse scale inhibition, filtration and ultraviolet sterilization multistage processing, without chemical reagent, can efficiently scale inhibition sterilization, reduce equipment corrosion, reduce pollution discharge, and degree of automation is high, maintenance cost is low, avoid secondary pollution.

This invention relates to Furin / hydroxyl radical dual-responsive size-changing nanoparticles, their preparation, and applications. The Furin / hydroxyl radical dual-responsive size-changing nanoparticles use an AIE photosensitizer as the core and DSPE-PEG as the substrate. 2K MAL nanoparticles serve as carriers, with functional peptides coupled to their surfaces via Michael addition reactions. The core functional building block is a self-designed and custom-synthesized R1 peptide, which possesses a triple function: high specificity recognition by Furin protease, OH-responsive tyrosine oxidation cross-linking, and coupling with DSPE-PEG nanoparticles. Its simple sequence significantly enhances tumor selectivity. The peptide is covalently modified with natural peptides using a nanoprecipitation method, avoiding complex chemical modifications and exogenous orthogonal biological groups, thus mitigating the toxicity and synthesis costs of traditional systems. Under the dual conditions of Furin protease overexpression and the presence of OH, size transformation is triggered, enabling deep tumor penetration with small sizes and long-term intratumoral retention through in-situ large-size assembly, demonstrating clinical translational potential.

The invention relates to the technical field of biomedical materials, discloses a preparation method of a bone repair mineralized biological membrane capable of inducing gene expression and a product, and aims at solving the problems that an existing bone repair material HAP crystal is difficult to regulate and control, the mechanical activity and the biological activity are not matched, bone induction is weak, the process is complex and the like. The preparation method comprises the following steps: S1, preparing a decellularized small intestinal submucosa (SIS) membrane and sterilizing; s2, constructing a pDA-PAM (at) SIS composite membrane; s3, inducing directional growth of HAP through ion permeation biomimetic mineralization; and S4, cleaning and drying to obtain the HAP / SIS collagen mineralized biological membrane. The product contains an SIS collagen matrix and low-crystallinity nano HAP (the width is 4-20nm, the length is 31-105nm, and the product is oriented along a c axis), the tensile strength is greater than or equal to 13MPa, the elastic modulus is greater than or equal to 75MPa, the specific surface area is greater than or equal to 60m < 2 > / g, and osteogenic genes such as ALP, Runx2 and the like can be up-regulated by more than or equal to 2 times. The method is mild in process, easy to operate, good in biocompatibility, high in bone conduction and inductivity, suitable for large-scale production and capable of meeting the clinical bone defect repair requirement.

The present application relates to the technical field of contact lens disinfectant, and discloses a hard corneal contact lens care solution and a preparation process thereof. The hard corneal contact lens care solution comprises a multiple antibacterial system. The multiple antibacterial system comprises antibacterial peptides, beta-cyclodextrin-PHMB inclusion compound, zinc-doped mesoporous silica loaded with silver and HEMA-dopamine liposomes. In the zinc-doped mesoporous silica loaded with silver, mesoporous silica is used as a skeleton material, zinc is doped in the mesoporous silica skeleton material in the form of lattice doping, and silver is loaded in the mesoporous channel. The present application is prepared by using a multiple antibacterial system. Through the synergistic effect of the components of the prepared raw materials, the antibacterial performance is improved as a whole, the cytotoxicity is inhibited, good lubrication durability and active ingredient stability are achieved, and the stability and efficiency of the sterilization and disinfection effect are improved by combining a specific sterilization process.