69results about How to "Improve gene transfection efficiency" patented technology

The invention provides a preparation method of a chitosan grafted polyethyleneimine non-viral transgene vector. The preparation method comprises the following steps: obtaining thiolated polyethyleneimine and thiolated chitosan; taking oxidation reaction to thiolated polyethyleneimine and thiolated chitosan to form a disulfide bond, and obtaining the chitosan grafted polyethyleneimine non-viral transgene vector. The invention further provides an application of the preparation method of the chitosan grafted polyethyleneimine non-viral transgene vector in gene transfection. The chitosan grafted polyethyleneimine non-viral transgene vector comprises the reduction sensitive disulfide bond, can quickly degrade and release DNA (deoxyribonucleic acid) in the reduction environment due to higher content of glutathione in a cell, and express excellent biocompatibility and high transfection efficiency, so that the chitosan grafted polyethyleneimine non-viral transgene vector is a low-toxicity and efficient non-viral transgene vector, and has a wide application prospect.

The invention provides an application of a fluorine-containing aliphatic chain-modified cationic polymer in enhancement of gene transfection efficiency. The invention provides the fluorine-containing aliphatic chain-modified cationic polymer and the application of the fluorine-containing aliphatic chain-modified cationic polymer as a non-virus gene carrier. The fluorine-containing aliphatic chain is covalently linked with the cationic polymer surface; the cationic polymer comprises linear polyethyleneimine, branched polyethyleneimine, linear polylysine, polylysine dendrimer, polypropyleneimine dendrimer, polyamide-amine dendrimer and its derivative; the genes comprise DNA, siRNA, shRNA, microRNA and modified nucleic acid. The toxicity of the fluorine-containing aliphatic chain-modified cationic polymer is little, and can realize high efficiency gene transfection under low nucleic acid dosage and material amount condition, and the gene transfection efficiency in a plurality of cells is obviously better than that of the commercial transfection reagents such as Lipofectamine2000.

The invention discloses a poly(methyl)acrylamide cationic polymer modified by natural arginine on a side chain, a preparation method and an application. The (methyl)acrylamide polymer with tert-butyloxycarbonyl (Boc) protected amino group on the side chain is synthesized by reversible addition-fragmentation chain transfer (RAFT) polymerization; arginine containing a protection group is linked to a poly(methyl)acrylamide molecule by using the amino group with the protection group on the side chain removed; and the cationic functional polymer is obtained after the protection group is removed. The preparation method is simple and mild in conditions. The poly(methyl)acrylamide cationic polymer modified by natural arginine on the side chain has low cytotoxicity and high biocompatibility, can combine genes efficiently, has high gene transfection efficiency, is an effective non-viral gene vector, and is used for in-vitro gene transfection reagent.

The invention discloses a novel cationic polymer used as a non-viral gene carrier as well as a preparation method and application thereof. The cationic polymer provided by the invention has a structure shown as the following formula I. The cationic polymer has a 1,2,3-triazole group structure and a disulfide bond structure and is generated by an alkynylation monomer and an azide monomer (an azide-diethylene glycol monomer and an azide monomer containing a disulfide bond) through cycloaddition and polymerization of alkynyl-azide catalyzed by single-charge copper ions. The polymer provided by the invention has a structure in which triazole is adjacent to amide, and the structure has specific binding ability with nucleic acid, thus, the stability of genes in the transmission process can be improved; and the disulfide bond contained in the structure also has reduction responsiveness and can be degraded in a cell to further increase the transfection efficiency and lower the toxicity, therefore, the non-viral gene carrier prepared by using the polymer has the characteristics of high biocompatibility, low toxicity, high transfection efficiency and the like.

The invention discloses a histamine-modified agmatine-based linear-polymer transgenic carrier and a preparation method and applications thereof. The transgenic carrier is prepared through reacting open loops of epoxy groups of glycidyl methacrylate with amino end groups of agmatine and histamine, chaining the agmatine and the histamine to the glycidyl methacrylate through chemical bonds, initiating a modified glycidyl methacrylate monomer to carry out free-radical atactic polymerization, and finally chaining the electropositive agmatine and the histamine with a proton buffering function to macromolecule chains. The agmatine carrier has good biocompatibility and promotes the transmembrane capacity of composites. The modification of the histamine increases the endosome escape capability of composites on the premise of not affecting the cell toxicity of the carrier, thereby effectively improving the efficiency and properties of the agmatine as a transgenic carrier; and the carrier can be used as an efficient non-viral gene carrier for gene therapy, realizes the improvement on the gene transfection efficiency of the agmatine carrier, and extends the role of the in-vivo circulation time.

The invention provides a TA polypeptide, a TA polypeptide-modified drug delivery system, a preparation method of the TA polypeptide-modified drug delivery system and application of the TA polypeptideand TA polypeptide-modified drug delivery system. The polypeptide contains an amino acid sequence RKKRRQRRR and an amino acid sequence ATWLPPR, and has the ability of penetration of biological barriers, and the proliferation, migration and other activity of new vessels can be inhibited through target binding to VEGFR-2 and NRP-1 receptors. The polypeptide can be applied to targeted therapy and diagnosis of tumor angiogenesis, after the gene drug delivery system is modified by the TA polypeptide, therapeutic genes can be carried, and penetrate a blood-brain barrier BBB and a blood-tumor barrierBBTB, and uptake and expression of gene drugs at sites of tumors and angiogenesis, so that targeted therapy for in-situ glioma is achieved effectively.

The invention provides arginine modified polyethyleneimine. The arginine modified polyethyleneimine is obtained by replacing primary amine hydrogen of primary amine groups in polyethyleneimine with arginine. The molecular weight of the polyethyleneimine is less than 10000. As a gene vector, the arginine modified polyethyleneimine prepared by the invention has good plasmid DNA loading capacity, very low cytotoxicity and very high gene transfection efficiency, the transfection efficiency is higher than that of the existing product in the presence or absence of serum, and the transfection efficiency of low-molecular-weight polyethyleneimine is remarkably improved. The arginine modified polyethyleneimine provided by the invention can be used as an excellent gene vector.

The invention discloses a nano composite gene carrier and a preparation method thereof. The gene carrier comprises a magnetic nano core, a shell 1 and a shell 2, the shell 1 and the shell 2 coat the magnetic nano core which is closely matched with the shell 1, the shell 1 and the shell 2 are closely matched, the magnetic nano core is made of Fe3O4, the shell 1 is made of, and the shell 2 is made of. The gene carrier has magnetic response characteristics, guidability of gene transfection is enhanced, gene transfection efficiency is improved, and the gene carrier has high biocompatibility and high gene transfection efficiency, is recyclable and can lower cost of gene transfection.