12results about How to "Avoid cytotoxicity" patented technology

The invention belongs to the technical field of medical materials, and particularly relates to a degradable wound dressing and a preparation method thereof. Compared with the prior art, the degradable wound dressing prepared by the preparation method disclosed by the invention is a completely biodegradable Janus composite film, and a hydrophobic inner layer and a hydrophilic outer layer are obtained by selecting different materials; the material PGA with excellent biological performance is utilized, the problem that electrostatic spinning cannot be carried out through pure PGA is solved, PGA and gelatin are creatively mixed, the advantages of PGA and gelatin are combined, and the PGA / Gel electrostatic spinning film which is high in toughness, high in tensile strength, good in biocompatibility and high in medicine carrying efficiency is obtained; meanwhile, the functions of resisting bacteria, resisting inflammation, discharging seepage and promoting angiogenesis are achieved, and the wound healing rate is effectively guaranteed.

The invention relates to the technical field of biological material manufacturing, in particular to vanadium-doped mesoporous bioactive glass powder for treating diabetic wounds and a preparation method of the vanadium-doped mesoporous bioactive glass powder. Adding an ammonia solution into the template agent solution to obtain a mixed solution; adding a silicon source, a phosphorus source, a calcium source and a vanadium source into the mixed solution in batches according to a preset interval time under a continuous stirring condition, continuously stirring and reacting for 5.5-24 hours, and centrifuging and collecting a precipitation product; and washing, roasting and grinding the obtained precipitation product to obtain the vanadium-doped mesoporous bioactive glass powder for treating diabetic wounds.

The invention relates to the technical field of cell transfection experiment methods, and aims at effectively solving the cell liposome transfection tolerance phenomenon by increasing circulating cell hydrostatic pressure treatment in a cell liposome transfection experiment to improve the liposome transfection efficiency. In a cell liposome transfection experiment, the liposome transfection efficiency is improved by adding cell hydrostatic pressure treatment of a circulating mode; the circulation mode is that the hydrostatic pressure of the cells is maintained to be periodically changed in a set pressure interval value under a set frequency. The cell lipidosome transfection tolerance phenomenon is improved, and especially the transfection efficiency of lipidosome transfection tolerance cells such as primary culture cells and suspension culture cells is improved.

The invention relates to the technical field of medical instruments, in particular to an ERCP novel bile duct stent and a preparation method thereof.The bile duct stent prepared through the preparation method has certain antibacterial ability by using an AMP-Chol12 peptide chain with the antibacterial ability, the bacterial membrane structure is destroyed through the electric charge effect, bacterial death is caused, and the bile duct stent has a certain antibacterial ability. Therefore, the bacterial infection risk is reduced. The physical antibacterial mechanism does not depend on chemical release, so that the antibacterial property is lasting, silver ions and antibiotics are not contained, bacterial drug resistance is not caused, meanwhile, good biocompatibility is achieved, the lubricating property can be improved, friction and damage are reduced, and bile sludge deposition is reduced.

This invention relates to the field of biomedical materials, specifically to an antibacterial hydrogel, its preparation method, and its applications. The method involves first preparing thiolated tannic acid and copper-doped Prussian blue nanozyme (CuPB). Methacrylated gelatin is mixed with the thiolated tannic acid, followed by the sequential addition of CuPB, ε-polylysine, trehalose, horseradish peroxidase, and a photoinitiator. The mixture is stirred until homogeneous to obtain a photosensitive prepolymer solution, which is then photocured under visible light to obtain the antibacterial hydrogel. The antibacterial hydrogel prepared by this invention responds to changes in H2O2 concentration at the wound site: during infection, CuPB and HRP cascade catalyze the generation of reactive oxygen species, synergistically with ε-polylysine and copper ions to achieve multi-mechanism, highly efficient antibacterial action; simultaneously, it triggers oxidative crosslinking of the thiolated tannic acid, enhancing its mechanical properties and accompanied by color changes, thus aiding in monitoring the infection status; possessing excellent biocompatibility, antibacterial properties, and mechanical properties, it can be used in wound dressings, biosensors, and other fields.

The invention provides a preparation method and application of a rhodiola rosea extracellular vesicle targeted drug delivery system with an anti-melanoma effect. The rhodiola rosea extracellular vesicle targeted drug delivery system is DP-pYEEIE-RELNs-DOX, the rhodiola rosea extracellular vesicle RELNs is used as a carrier, a drug doxorubicin DOX is loaded, and DP-pYEEIE with a targeting effect is modified on the rhodiola rosea extracellular vesicle RELNs, so that the rhodiola rosea extracellular vesicle targeted drug delivery system DP-pYEEIE-RELNs-DOX is constructed; wherein the DP-pYEEIE is a Caffeic acid-pYEEIE modified DSPE-PEG (Distearoyl Phosphate Polyethylene-Polyethylene Glycol) (Distearoyl Phosphate Polyethylene Glycol). And the DP-pYEEIE-RELNs-DOX can be used for remarkably inhibiting the proliferation of the A375 cells. The compound has better cell uptake and cell division prevention capabilities.

This invention relates to the field of biomedical technology, providing a microsphere composition and its preparation method, as well as its application in the preparation of contrast agents and drugs. The microsphere composition includes a microsphere dispersant and microsphere particles; the microsphere particles include a shell and a core; the shell comprises a lipid mixture consisting of charged lipids and auxiliary lipids; the core comprises an optional therapeutic gas, and one or both of an inert gas or inert liquid; the molar amount of charged lipids is ≤60% based on the total molar amount of the lipid mixture; the pH value of the microsphere dispersant is 5-6.9. The microsphere particles of this invention can efficiently load therapeutic gases and conventional drugs, precisely target their application, exhibit excellent stability, and have high biocompatibility.

The invention provides a supported cationic polymer as well as a preparation method and application thereof, and belongs to the technical field of material science. The supported cationic polymer takes an acrylamide aqueous solution, a polysaccharide aqueous solution and a cationic polymer aqueous solution as main raw materials. The preparation method comprises the following steps: fully mixing acrylamide, a cross-linking agent accounting for 0.1-1% of the mass of acrylamide and an initiator accounting for 0.1-0.5% of the mass of acrylamide in proportion, stirring at a low speed to uniformly dissolve the cross-linking agent and the initiator, then adding a catalyst accounting for 0.5-1% of the total mass of the system, fully stirring until a viscous solution is obtained, finally injecting the viscous solution into a porous mold, and carrying out vacuum drying, so as to obtain the water-soluble acrylamide. And then transferring into a drying oven at 60-80 DEG C, and reacting for 3-6 hours to obtain the polysaccharide-based antibacterial hydrogel dressing. The method has the advantages of high biological safety, low cost and the like.

The present invention relates to the field of RNA interference technology, and in particular to an RNA interference viral vector, wherein the RNA interference viral vector expresses shRNA carried by a miR-AB framework based on human miR-30pri-miRNA mir to interfere with the expression of target genes; the miR‑AB sequence is regulated by a variety of eukaryotic promoters; the RNA interference virus vector traces cells that have RNA interference through fluorescent protein reporters, or screens cells that have RNA interference through antibiotics. Among them, the miR‑AB sequence in the RNA interference virus vector is regulated by a variety of eukaryotic promoters, which is conducive to its application in a variety of eukaryotic cells, and the viral vector can rely on its Puromycin resistance to screen cells that have RNA interference through antibiotics, and can also rely on its fluorescent protein reporter molecules to trace cells that have RNA interference. Therefore, it can simultaneously perform single-gene interference and multi-gene arbitrary combination interference on multiple target genes in eukaryotic cells through a variety of viral co-infection methods, thereby simultaneously analyzing the functions of multiple target genes in eukaryotic cells.

The present invention provides a cryopreservation solution, a preparation method and a use method for kidney organoids, and relates to the field of cell and tissue engineering technology. The cryopreservation solution includes the following components by weight: 4.7 to 5.3 parts of cell cryopreservation solution; 3.5 to 4.5 parts of KOSR serum substitute; 0.8 to 1.2 parts of improved culture medium; wherein the improved culture medium includes RPMI 1640 culture medium and L-alanyl-L-glutamine, and the weight of RPMI 1640 culture medium is 3.5 to 4.5 times that of L-alanyl-L-glutamine. KOSR serum substitute and improved culture medium are added to CS10 cell cryopreservation solution to dilute the concentration of dimethyl sulfoxide, so that the dimethyl sulfoxide in the cryopreservation solution reaches the required minimum concentration, which not only reduces the formation of ice crystals, but also avoids the cytotoxicity caused by the excessively high concentration of dimethyl sulfoxide, thereby reducing the damage of kidney organoids.

The embodiment of the invention provides an implantable piezoelectric / conductive double-layer composite membrane, a stent, a preparation method and application thereof, and belongs to the field of tissue engineering and biological materials. The implantable piezoelectric / conductive double-layer composite film is composed of a composite conductive biological material layer and a piezoelectric layer, the piezoelectric layer is attached to and covers the composite conductive biological material layer, the composite conductive biological material layer is composed of chitosan and chitosan grafted reduced graphene oxide, and the piezoelectric layer is composed of piezoelectric fibers. The piezoelectric / conductive double-layer composite film provided by the invention not only provides enough mechanical structure support, but also provides good conductivity and electric signal output capability, has remarkable antibacterial performance, and has a better promotion effect on regeneration and repair of peripheral nerves.

The invention discloses anti-infection wound repair promoting hydrogel, a preparation method and application, firstly, polydopamine microspheres are prepared according to a dopamine oxidation auto-polymerization principle, then antibacterial peptide is embedded into the polydopamine microspheres, and antibacterial peptide-coated polydopamine microspheres are obtained; and then the antibacterial peptide coated polydopamine microspheres are introduced into pullulan and gelatin composite hydrogel, so that the anti-infection hydrogel capable of promoting wound repair is prepared. Experimental results show that the anti-infection hydrogel capable of promoting wound repair has no stimulation effect on wounds, is safe and free of toxic and side effects, can be attached to the wounds, has long-acting and stable antibacterial, anti-inflammatory, pain-relieving and repair-promoting effects, effectively promotes wound healing and repair, protects wounds from infection, and has excellent biocompatibility and biodegradability. In addition, the preparation method is simple to operate and convenient for large-scale popularization and application.