8 results about "Peptide modification" patented technology

This invention discloses an arginine-glycine-aspartic acid (RGD) peptide-modified chiral atomically precise metal nanoclusters, their preparation, and applications. The RGD peptide-modified chiral atomically precise metal nanoclusters consist of an atomically precise metal core, a chiral RGD peptide ligand layer, and linking molecules connecting the metal core and ligand layer. The chiral regulation and targeting functions of the RGD peptide-modified chiral atomically precise metal nanoclusters synergistically enhance their targeting and penetration at the tissue and cellular levels, thereby improving their uptake efficiency. After optimization with α... v The binding constant of β3 integrin is 1.4 × 10⁻⁶. ‑6 M ‑1 RGD peptides modify the ultrasmall metal cores of chiral atomically precise metal nanoclusters, endowing them with highly efficient and rapid renal clearance properties. This invention provides a solution suitable for various α-cell tumors, arthritis, liver fibrosis, and other conditions. v RGD peptides modified with chiral atomic precision metal nanoclusters, used to treat diseases with high expression of β3 integrin, can achieve efficient enrichment at target sites for imaging.

This invention relates to the field of biomedical materials and pharmaceutical formulations, disclosing an FH peptide-polydopamine-coated graphene oxide drug delivery system and its preparation and application. The system includes an RGD peptide-modified graphene oxide carrier, a polydopamine shell, and a drug loaded within the system. The polydopamine shell is surface-modified with an FH peptide. The drugs include docetaxel and losartan, with docetaxel loaded on the RGD peptide-modified graphene oxide carrier and losartan loaded in the FH peptide-modified polydopamine shell. This FH peptide-polydopamine-coated graphene oxide drug delivery system, through surface modification of graphene oxide with an RGD peptide and coating with a polydopamine shell, effectively shields against the potential cytotoxicity and blood incompatibility risks of unmodified graphene oxide. Compared to unmodified graphene oxide carriers, this system shows significantly improved compatibility at both normal and tumor cell levels, maintaining extremely high cell viability across a wide concentration range.

This specification describes a method for the late modification of peptides and functionalized peptides. The method is specific and robust and allows for the precise construction of C2-sulfenylated tryptophan using sulfenyl reagents such as thiosulfonic acid ester (ArSO2SR) reagents. This simple C2-sulfenylation process allows for the easy introduction of a variety of functional groups, such as SCF3, SCF2H, SCF2Br, SCHFCl, SCF2-alkyl groups, SCHF-alkyl groups, S-alkyl groups, and S-aryl groups, into peptides, particularly tryptophan residues of natural peptides. Generally, a late peptide modification method comprises (i) the step of maintaining a reaction mixture at a sufficient temperature for a sufficient time to produce a product. The reaction mixture comprises a peptide to be modified containing one or more tryptophan residues, a sulfenyl reagent, and a solvent. The product produced in step (i) comprises a sulfenylated peptide, wherein the sulfenylation has occurred in at least one of the one or more tryptophan residues of the peptide.

Disclosed are a cartilage endplate-targeting composite hydrogel, a preparation method therefor, and use thereof. The cartilage endplate-targeting composite hydrogel comprises drug-loaded exosomes modified with a cartilage-targeting peptide, calcium carbonate, chitosan, and water; the drug-loaded exosomes modified with the cartilage-targeting peptide comprise exosomes, a cartilage-targeting peptide, and salvianolic acid A. The cartilage endplate-targeting composite hydrogel is prepared by encapsulating salvianolic acid A in human mesenchymal stem cell-derived exosomes, modifying the human mesenchymal stem cell-derived exosomes with a cartilage-targeting peptide to obtain drug-loaded exosomes modified with the cartilage-targeting peptide, and then mixing the drug-loaded exosomes modified with the cartilage-targeting peptide with calcium carbonate, chitosan, and water.

The present application relates to a kind of agglutinin joint targeting peptide modified nanosphere and its preparation method and application, belong to the biomedicine technical field.To solve the problem that the existing drug delivery system is difficult to have the integration of nasal brain barrier breakthrough, nasal long-term retention, brain lesion targeting, broad-spectrum drug loading and high biological stability, the present application provides a kind of agglutinin joint targeting peptide modified nanosphere, including polymer matrix core, biomimetic cell membrane shell and double-ligand functionalization surface crown layer in turn from inside to outside.The nanosphere of the present application can prolong the nasal retention time and efficiently penetrate the nasal mucosa barrier by relying on the synergistic effect of core-shell-crown three-layer structure, realize transnasal brain and lesion precise targeting, improve drug delivery efficiency and efficacy, and reduce toxic side effects.The nanosphere of the present application has a wide range of drug loading spectrum, suitable for the drug demand of various central nervous system diseases, and has excellent clinical transformation value and application prospect.

The application provides an engineered DNAzyme molecular machine and its application, including one or two groups of chain group one and chain group two, chain group one: i-motif chain modified DNAzyme and its substrate chain, the chain group one is modified on the surface of cancer cells and T cells, the acid microenvironment of tumor cells is used to make the modified i-motif chain contract, and the distance between the cancer cells and the tumor cells is shortened; chain group two: mitochondria-targeting peptide modified DNAzyme and its substrate chain, intracellular mitochondrial aggregation is used to induce apoptosis. The tumor microenvironment responsive control of cell behavior outside and inside cells based on DNAzyme includes cell recognition, intercellular proximity, separation after treatment and mitochondrial aggregation, which not only provides a useful way for regulating intercellular interaction, but also provides a powerful targeted cancer treatment method without killing normal cells.

This invention discloses a tumor microenvironment-responsive enzyme prodrug conversion nanocomposite and its preparation method, belonging to the field of nanomedicine delivery technology. The nanocomposite comprises a core layer containing a β-glucuronidase H560N mutant, a targeting layer coupled with an anti-HER2 scFv, and a PEG protective layer modified with an MMP-2 sensitive peptide. The H560N mutation inhibits enzyme activity at neutral pH and restores it at acidic pH. After the nanocomposite is cleaved by MMP-2 to expose the targeting ligand, it is internalized by tumor cells. The acidic lysosomal environment activates the enzyme activity to convert the prodrug. The preparation method includes enzyme mutant expression and purification, maleimide-thiol coupling with scFv, and aqueous self-assembly to form the nanocomposite. This invention achieves precise enzyme prodrug therapy with dual spatiotemporal responses.

The application relates to the technical field of the cross of microfluidic technology, chemical synthesis and biomedicine, and discloses a method for preparing EGFR CAR-NK cells based on polypeptide gel droplet confined transfection technology and application, which comprises the following steps: (1) preparing collagen-mimic-peptide-modified alginate; (2) constructing a confined transfection system: adopting a droplet microfluidic chip, wrapping NK cells and slow virus carrying an EGFR CAR gene in the collagen-mimic-peptide-modified alginate droplet prepared in the step (1), and obtaining a gel droplet after gelation of the droplet; and (3) confined transfection and cell culture. The method can significantly reduce the dosage of slow virus and cell toxicity, greatly improve the transfection success rate of the CAR gene, the survival rate and functional activity of the NK cells, and finally obtain EGFR CAR-NK cell products with higher purity and stronger target killing capacity.