Preparation method and application of a tumor-targeting biomimetic nanodrug

Abstract

The application relates to the fields of biological medicine and nanomedicine technology, and discloses a preparation method and application of a tumor-targeting bionic nanodrug, which comprises the following steps: constructing a three-dimensional nanostructure core through DNA origami, performing site-specific modification on the surface of the three-dimensional nanostructure core, precisely loading a chemotherapeutic drug, an immunoadjuvant or an enzyme catalyst in the three-dimensional nanostructure core, and integrating a dynamic element responding to a tumor microenvironment to realize intelligent drug release. Through the fusion of the DNA self-assembly principle of structural biology, the algorithm modeling of computer science and the precise coupling technology of synthetic chemistry, a bionic nanorobot with programmable structure, accurate drug loading site, high targeting efficiency and intelligent response is constructed, the controllability of the structure of the nanodrug, the targeting efficiency and the on-demand release performance of the nanodrug are significantly improved, the technical bottlenecks of traditional nanocarriers in the aspects of structure control, drug loading precision and targeting efficiency are solved, and the bionic nanorobot is suitable for precise treatment of various solid tumors.

Description

Technical Field

[0001] This invention belongs to the field of biomedicine and nanomedicine technology, specifically a method for preparing and applying a targeted tumor biomimetic nanomedicine. Background Technology

[0002] Biomimetic nanomedicine delivery systems, by mimicking the structure and function of natural cell membranes, endow nanocarriers with excellent biocompatibility, immune escape capabilities, and targeted recognition properties, showing broad application prospects in the field of tumor treatment. Current technologies often employ erythrocyte membranes, cancer cell membranes, macrophage membranes, etc., to coat the surface of the nanocore to achieve functions such as long circulation, homologous targeting, or inflammatory chemotaxis.

[0003] Patent CN119405835A discloses a GSH-responsive cell membrane biomimetic nanomedicine, which uses an immune cell membrane overexpressing an azide compound as a carrier. A bioconjugate containing a -SH group is linked to a small molecule inhibitor via click chemistry using disulfide bonds. This design utilizes the high concentration of GSH in the tumor microenvironment to trigger drug release, improving the selective release efficiency of the drug at the lesion site. However, this approach relies on genetically engineering the cell membrane to overexpress an azide group. The preparation process involves complex cell culture and membrane modification steps, requiring high purity and functional integrity of the extracted cell membrane, which may affect the stability and reproducibility of large-scale production. Furthermore, the drug is only covalently linked to the membrane surface via disulfide bonds, limiting the drug loading capacity and failing to fully integrate the synergistic mechanisms of passive targeting (such as the EPR effect) and active targeting (such as receptor-ligand recognition).

[0004] Patent CN118416017A discloses a biomimetic metal-organic framework (MOF) nanomedicine encapsulating chlordamine in tumor cell membranes. The method employs a one-pot synthesis of the MOF drug-loaded core, followed by physical extrusion to coat the tumor cell membrane onto its surface. This approach utilizes the high porosity of MOF materials to effectively encapsulate the hydrophobic drug chlordamine and enhances tumor accumulation through the homologous targeting of the tumor cell membrane. However, in this technology, the drug is merely physically embedded within the MOF channels, lacking precise control over its release behavior, potentially leading to premature drug leakage during blood circulation. Furthermore, the extraction and encapsulation process of the tumor cell membrane does not introduce additional functional modifications, making it difficult to achieve precise intervention on specific tumor subtypes or the immune microenvironment, thus limiting its universality and therapeutic depth in complex tumor models.

[0005] In summary, existing biomimetic nanomedicines still have room for improvement in terms of high drug loading efficiency, structural controllability, multi-target synergy, and microenvironment-responsive release. There is an urgent need to develop a novel targeted tumor biomimetic nanomedicine system with simple preparation process, well-defined drug loading sites, diverse targeting mechanisms, and precisely regulated release behavior. Summary of the Invention

[0006] This invention provides a method for preparing and applying targeted tumor biomimetic nanomedicines. It aims to construct biomimetic nanorobots with precise three-dimensional structures, programmable drug loading sites, and intelligent response release functions through DNA origami programming. Tumor cell-specific aptamers are modified on the surface of the nanorobots to achieve active targeted recognition, and chemotherapy drugs, immune adjuvants, or enzyme catalysts are precisely loaded inside. This solves the technical problems of poor structural controllability, inaccurate drug loading sites, and low efficiency of targeted molecule modification in traditional nanocarriers.

[0007] This invention provides a method for preparing targeted tumor biomimetic nanomedicines, comprising the following steps: S10: Based on the sequence information of the target tumor cell surface markers, design and synthesize a single-stranded circular DNA scaffold strand (M13mp18 phage genome or its engineered variant) with a length of 7000-8500 nucleotides. According to the preset three-dimensional geometric configuration, use computer-aided structural modeling software (such as caDNAno, DAEDALUS or Tiamat) to generate the corresponding DNA origami structure blueprint and determine the sequence, number and spatial arrangement of the required short-strand staples. S20: The scaffold chain and the chemically modified staple chain are mixed at a molar ratio of 1:100 to 1:200 in an annealing buffer system containing 10-20 mmol / L Tris-HCl buffer, 1-5 mmol / L ethylenediaminetetraacetic acid, and 10-20 mmol / L magnesium chloride. The mixture is then placed in a thermal cycler for programmed annealing. The annealing program is as follows: hold at 95°C for 5 min, and then cool down to 20-25°C at a rate of 1-2°C per hour, finally forming a DNA origami nanocarrier with a preset three-dimensional structure. S30: Functionalized ends containing -SH, -NH2, or -N3 are introduced into the staple chain, so that the functional groups of some staple chains are exposed at specific positions on the surface of the nanocarrier after the origami structure is assembled; then, tumor cell-specific aptamers (such as AS1411, Sgc8, EpDT3, etc.) are covalently coupled to the functionalized ends through bifunctional crosslinking agents (such as SMCC, DBCO-NHS, Sulfo-LC-SPDP), so as to achieve site-specific and directional modification of the aptamers on the surface of the nanocarrier, and the molar ratio of aptamers to staple chains is 1:1 to 1:5; S40: Several cavity or channel regions are designed inside the DNA origami structure. Base sequences that can interact non-covalently with drug molecules are introduced on the staple chains corresponding to these regions (e.g., GC-rich regions are used for embedding doxorubicin, or AT-rich regions are used for embedding paclitaxel). Alternatively, reactive groups that can be covalently linked with drugs are introduced at the ends of the staple chains (e.g., maleimide groups are used to link the thiol-containing immune adjuvant CpGODN, or DBCO groups are used to click-link the azide-containing enzyme catalyst). Chemotherapy drugs, immune adjuvants, or enzyme catalysts are added to the surface-modified DNA origami nanocarrier solution in a predetermined ratio and incubated at 4-25°C for 12-48 hours to allow drug molecules to be precisely loaded onto preset sites through intercalation, electrostatic adsorption, or covalent bonding. S50: Introduce dynamic structural elements sensitive to tumor microenvironment-specific stimuli (such as low pH, high concentration of glutathione, specific proteases) into the DNA origami structure. These dynamic structural elements are composed of cleavable staple chains containing acid-sensitive acetal bonds, reducing environment-sensitive disulfide bonds, or matrix metalloproteinase (MMP-2 / 9)-sensitive polypeptide sequences (such as PLGLAG). When the nanocarrier enters the tumor microenvironment, the dynamic structural elements are specifically triggered to break, causing a conformational change in the DNA origami structure, exposing the internal drug-loading region, and realizing intelligent response release of the drug. S60: Optionally, the drug-loaded DNA origami nanorobot is coated with a natural cell membrane (such as a red blood cell membrane, a cancer cell membrane, or a macrophage membrane) by extrusion or ultrasonic fusion to form a composite nanomedicine with a biomimetic shell, wherein the mass ratio of the cell membrane to the DNA origami core is 1:1 to 3:1, and the extrusion process uses a polycarbonate membrane with a pore size of 100-200 nm, and the extrusion is repeated 10-20 times.

[0008] This invention utilizes DNA origami programming to construct nanocarriers whose three-dimensional structure is precisely controlled by hundreds of staple chains. Each drug-loading site and target molecule modification site is determined through computer modeling during the design phase, avoiding the structural uncontrollability issues caused by the randomness of self-assembly in traditional liposomes, polymer micelles, or inorganic nanoparticles. Aptamers are chemically coupled and site-specifically modified at predetermined locations, significantly improving the spatial orientation and binding efficiency of target molecules. Drug loading achieves site specificity through base sequence programming or covalent linkage, avoiding drug load fluctuations and premature leakage caused by physical embedding. The introduction of dynamic structural elements enables conformational changes in the nanocarrier within the tumor microenvironment, achieving on-demand release rather than relying on passive diffusion.

[0009] In step S10, the three-dimensional geometric configuration is selected from cubes, octahedrons, tubular, cage-like or virus-like capsid structures, with a size range of 50-200 nm.

[0010] In step S20, the magnesium chloride concentration in the annealing buffer system is 12-18 mmol / L, and the annealing cooling rate is 1.5°C per hour.

[0011] In step S30, the functionalized staple chain accounts for 5%-15% of the total number of staple chains, and its modification position is located at the vertex, edge or center of a specific surface of the nanocarrier to optimize the spatial accessibility of the aptamer.

[0012] In step S30, when the bifunctional crosslinking agent is SMCC, the reaction conditions are phosphate buffer solution at pH 7.2-7.6, and the reaction is carried out at room temperature in the dark for 2-4 hours.

[0013] In step S40, the chemotherapy drug is selected from doxorubicin, cisplatin, paclitaxel or their derivatives; the immune adjuvant is selected from CpG oligodeoxynucleotide (ODN), Poly(I:C) or R848; and the enzyme catalyst is selected from glucose oxidase, catalase or lysozyme.

[0014] In step S40, the covalent connection is carried out by a copper-catalyzed azido-alkyne cycloaddition reaction or a copper-strain-free azido-alkyne cycloaddition reaction, and the reaction is carried out at 4°C for 24 hours.

[0015] In step S50, the acetal bond sensitive to low pH is achieved by introducing a 1,3-dioxolane-modified deoxyuridine into the staple chain; the disulfide bond sensitive to reducing environment is formed by introducing thiol groups at the ends of two adjacent staple chains and then oxidizing them with air; the polypeptide sequence sensitive to MMP-2 / 9 is embedded in the middle of the staple chain by solid-phase synthesis.

[0016] In step S50, the number of dynamic structural elements is 1-5, distributed in the gating area of ​​the drug-loading chamber to ensure a balance between structural stability and response sensitivity.

[0017] In step S60, the cell membrane is extracted from human erythrocytes and purified by hypotonic lysis, differential centrifugation and ultracentrifugation. The integrity of the membrane proteins is verified by SDS-PAGE.

[0018] In step S60, the parameters of the ultrasonic fusion method are: power 100-150 watts, pulse mode (on for 2 seconds, off for 3 seconds), total duration 5-10 minutes, performed under ice bath conditions.

[0019] This invention provides a targeted tumor biomimetic nanomedicine, which is prepared by the preparation method described in any embodiment of the first aspect. The nanomedicine includes a three-dimensional nanostructure core constructed by DNA origami. The surface of the core is modified with tumor cell-specific aptamers at predetermined sites. One or more combinations of chemotherapeutic drugs, immune adjuvants, or enzyme catalysts are precisely loaded at predetermined sites inside the core. The core contains dynamic structural elements that are sensitive to specific stimuli of the tumor microenvironment and can undergo conformational changes and release the loaded drugs upon stimulation.

[0020] According to the present invention, the nanomedicine has a structural precision at the nanoscale, with a drug loading site error of less than 5 nm, an aptamer modification density of 10-100 molecules per particle, and uniform spatial distribution. Under physiological conditions (pH 7.4, GSH concentration 2-10 μmol / L), the drug leakage rate is less than 5%; in a simulated tumor microenvironment (pH 6.5, GSH concentration 2-10 mmol / L, MMP-9 concentration 100 ng / mL), more than 80% of the drug is released within 6-12 hours. This nanomedicine can simultaneously achieve EPR-mediated passive targeting, aptamer-mediated active targeting, and immune escape function conferred by a biomimetic membrane, forming a multi-targeting synergistic mechanism.

[0021] The three-dimensional core of the nanomedicine is a cubic structure with a side length of 80 nm. Each of the eight vertices on the surface is decorated with an Sgc8 aptamer, and each of the six internal faces has a drug-carrying cavity at its center, which is loaded with doxorubicin and CpGODN, respectively.

[0022] The dynamic structural element of the nanomedicine is four staple chains containing disulfide bonds, which form the latch of the drug-loading cavity. The staples break in a high GSH environment, thus opening the cavity.

[0023] The nanomedicine is coated with a cell membrane derived from homologous tumor cells, and the membrane retains natural membrane proteins such as PD-L1 and EGFR, which enhances homologous targeting ability.

[0024] This invention provides the application of the aforementioned targeted tumor biomimetic nanomedicine in the preparation of drugs for treating solid tumors, including but not limited to breast cancer, lung cancer, colon cancer, melanoma, or glioblastoma.

[0025] The application includes administering the nanomedicine via intravenous injection at a dose of 0.5-5 mg of DNA origami core per kilogram of body weight, once every 3-7 days, for 2-6 consecutive administrations.

[0026] The nanomedicine, when used in combination with immune checkpoint inhibitors (such as anti-PD-1 antibodies), can reshape the tumor immune microenvironment and enhance the anti-tumor immune response by simultaneously delivering chemotherapy drugs and immune adjuvants.

[0027] Compared with the prior art, the beneficial effects of the present invention are: This invention integrates the DNA self-assembly principle of structural biology, the algorithm modeling of computer science, and the precise coupling technology of synthetic chemistry to construct a biomimetic nanorobot with programmable structure, precise drug delivery sites, high targeting efficiency, and intelligent response. It fundamentally solves the technical bottlenecks of traditional nanocarriers in terms of structural control, drug delivery accuracy, and targeting efficiency, and provides a brand-new technical platform for precision tumor treatment. Detailed Implementation

[0028] This invention provides a method for preparing and applying a tumor-targeting biomimetic nanomedicine. The overall structure of the tumor-targeting biomimetic nanomedicine includes a three-dimensional nanostructure core constructed using DNA origami techniques. The core's surface is site-modified with tumor cell-specific aptamers, and its internal components are precisely loaded with one or more combinations of chemotherapeutic drugs, immune adjuvants, or enzyme catalysts at predetermined sites. Furthermore, the core contains dynamic structural elements sensitive to specific stimuli from the tumor microenvironment. In some embodiments, the three-dimensional nanostructure core is coated with a natural cell membrane, forming a composite nanomedicine with a biomimetic shell.

[0029] The technical solution of the present invention will be described in detail below with reference to specific embodiments and comparative examples, so as to ensure that those skilled in the art can fully understand and implement the present invention.

[0030] Example 1: DNA origami configuration is cubic (80nm); aptamer is Sgc8 (modification density 50 per particle); dynamic element is disulfide bond (4); loaded with doxorubicin + CpGODN; no cell membrane coating; scaffold chain length 7800 nucleotides; Preparation process: DNA origami vector assembly → aptamer site-specific modification → precise drug loading → dynamic element integration → finished product.

[0031] Example 2: The DNA origami configuration is octahedral (100nm), and the rest of the formulation and process are the same as in Example 1; Preparation process: Same as in Example 1 (carrier configuration adjustment).

[0032] Example 3: The dynamic element is an acid-sensitive acetal bond; the rest of the formulation and process are the same as in Example 1. Preparation process: Same as in Example 1 (dynamic component replacement).

[0033] Example 4: The dynamic element is a PLGLAG polypeptide sequence, and the rest of the formulation and process are the same as in Example 1; Preparation process: Same as in Example 1 (dynamic component replacement).

[0034] Example 5: The drug loading is paclitaxel + glucose oxidase, and the rest of the formulation and process are the same as in Example 1; Preparation process: Same as in Example 1 (drug loading type adjusted).

[0035] Example 6: Coating red blood cell membranes (membrane to core mass ratio 2:1), the remaining formulation and process are the same as in Example 1; Preparation process: Same as in Example 1 (with the addition of a cell membrane coating step).

[0036] Example 7: The aptamer modification density is 10 particles / particle, and the rest of the formulation and process are the same as in Example 1; Preparation process: Same as in Example 1 (aptamer modification density adjustment).

[0037] Example 8: The aptamer modification density is 100 units / particle, and the rest of the formulation and process are the same as in Example 1; Preparation process: Same as in Example 1 (aptamer modification density adjustment).

[0038] Comparative Example 1: Liposomes as carriers (100 nm); physical adsorption aptamers; no dynamic response elements; loaded with doxorubicin + CpGODN; other processes were the same as in Example 1; Preparation process: Liposome preparation → Aptamer adsorption → Drug loading → Finished product.

[0039] Comparative Example 2: The DNA origami carrier has no dynamic response element; the rest of the formulation and process are the same as in Example 1; Preparation process: DNA origami assembly → aptamer modification → drug loading → finished product.

[0040] Test method: Targeting and drug delivery testing: flow cytometry to measure tumor cell uptake; high performance liquid chromatography to measure drug delivery efficiency and drug release rate; assessment of drug leakage in the physiological environment.

[0041] Treatment and safety testing: tumor inhibition rate was measured in an in vivo tumor-bearing mouse model; blood biochemical indicators were tested to assess biocompatibility; and immune evasion ability was observed.

[0042] Structural performance testing: Atomic force microscopy was used to observe the integrity of the DNA origami structure; the response sensitivity of dynamic elements was verified.

[0043] The test data comparisons are shown in Table 1 and Table 2.

[0044] Table 1 Comparison of drug loading efficiency, tumor cell uptake rate, and physiological environment leakage rate Test Project Drug loading efficiency (%) Tumor cell uptake rate (%) Physiological environment leakage rate (%) Example 1 88 92 4 Example 2 86 90 5 Example 3 87 91 3 Example 4 85 89 4 Example 5 84 90 5 Example 6 85 93 2 Example 7 88 78 4 Example 8 86 95 5 Comparative Example 1 65 60 20 Comparative Example 2 87 91 8 Table 2 Comparison of 12h release rate, tumor inhibition rate, and biocompatibility Test Project 12h release rate (%) Tumor inhibition rate (%) Biocompatibility Example 1 85 78 excellent Example 2 83 76 excellent Example 3 82 75 excellent Example 4 80 74 excellent Example 5 81 77 excellent Example 6 84 80 excellent Example 7 85 68 excellent Example 8 83 82 excellent Comparative Example 1 60 45 generally Comparative Example 2 35 52 excellent Examples 1-8 showed drug loading efficiency ≥84%, uptake rate ≥78%, and release rate ≥80%, which were far superior to the comparative examples. Comparative example 1 showed low drug loading and high leakage of traditional liposomes, while comparative example 2 showed uncontrolled release of unresponsive elements, confirming that DNA origami + dynamic response + site-specific targeting is the key to precision treatment.

[0045] Different carrier configurations are all compatible (Examples 1-2); the release efficiency of disulfide bond responsive elements is optimal (Example 1); cell membrane coating (Example 6) enhances immune escape and tumor suppression rates; aptamer modification density is increased (Examples 7→1→8), and targeted uptake and therapeutic effects are optimized simultaneously.

[0046] The embodiment features a programmable structure and precise drug loading sites; multiple targeting synergistic effects result in high tumor enrichment efficiency; intelligent release within the microenvironment reduces off-target toxicity; excellent biocompatibility makes it suitable for various solid tumors; and the preparation process is scalable with good batch stability.

[0047] Compared to traditional liposomes (Comparative Example 1), the drug loading efficiency of the example was improved by 35%, and the tumor inhibition rate was improved by 73%; compared to non-responsive elements (Comparative Example 2), the release rate was improved by 143%, and the tumor inhibition rate was improved by 54%, solving the industry problems of uncontrollable structure, poor targeting, and disordered release of traditional nanomedicines.

[0048] In summary, the method described in this invention, through the synergy of DNA origami technology and biomimetic design, can achieve precise targeted therapy for tumors with different parameter combinations, and is applicable to individualized treatment scenarios for various solid tumors.

[0049] The above are merely preferred embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A method for preparing a tumor-targeting biomimetic nanomedicine, characterized in that, Includes the following steps: S10: Based on the sequence information of the target tumor cell surface markers, design and synthesize a single-stranded circular DNA scaffold with a length of 7000-8500 nucleotides, and generate the corresponding DNA origami structure blueprint using computer-aided structural modeling software according to the preset three-dimensional geometric configuration, and determine the sequence, number and spatial arrangement of the required short-strand staples. S20: The scaffold chain and the chemically modified staple chain are mixed at a molar ratio of 1:100 to 1:200 in an annealing buffer system containing 10-20 mmol / L Tris-HCl buffer, 1-5 mmol / L ethylenediaminetetraacetic acid, and 10-20 mmol / L magnesium chloride. The mixture is then placed in a thermal cycler for programmed annealing. The annealing program is as follows: hold at 95°C for 5 min, and then cool down to 20-25°C at a rate of 1-2°C per hour to form a DNA origami nanocarrier with a preset three-dimensional structure. S30: Introduce functionalized ends containing thiol, amino, or azide groups into the staple chain, so that the functional groups of some staple chains are exposed at specific positions on the surface of the nanocarrier after the origami structure is assembled; then, a tumor cell-specific aptamer is covalently coupled to the functionalized ends through a bifunctional crosslinking agent, and the molar ratio of the aptamer to the staple chain is 1:1 to 1:

5. S40: Several cavity or channel regions are designed inside the DNA origami structure. Base sequences that can interact non-covalently with drug molecules are introduced on the staple chains corresponding to these regions, or reactive groups that can be covalently linked with drugs are introduced at the ends of the staple chains. Chemotherapy drugs, immune adjuvants or enzyme catalysts are added to the surface-modified DNA origami nanocarrier solution in a predetermined ratio and incubated at 4-25℃ for 12-48h, so that drug molecules are precisely loaded into the preset sites through intercalation, electrostatic adsorption or covalent bonding. S50: Introduce dynamic structural elements that are sensitive to tumor microenvironment-specific stimuli into the DNA origami structure. The dynamic structural elements are composed of cleavable staple chains containing acid-sensitive acetal bonds, reducing environment-sensitive disulfide bonds, or matrix metalloproteinase MMP-2 / 9-sensitive polypeptide sequences PLGLAG. S60: Optionally, the drug-loaded DNA origami nanorobot is coated with a natural cell membrane by extrusion or ultrasonic fusion to form a composite nanomedicine with a biomimetic shell, wherein the mass ratio of the cell membrane to the DNA origami core is 1:1 to 3:1, and the extrusion process uses a polycarbonate membrane with a pore size of 100-200 nm, and the extrusion is repeated 10-20 times.

2. The preparation method according to claim 1, characterized in that, In step S10, the three-dimensional geometric configuration is selected from cubes, octahedrons, tubular, cage-like or virus-like capsid structures, with a size range of 50-200 nm.

3. The preparation method according to claim 1, characterized in that, In step S20, the magnesium chloride concentration in the annealing buffer system is 12-18 mmol / L, and the annealing cooling rate is 1.5°C per hour.

4. The preparation method according to claim 1, characterized in that, In step S30, the functionalized staple chain accounts for 5%-15% of the total number of staple chains, and its modification position is located at the vertex, edge or center of a specific surface of the nanocarrier.

5. The preparation method according to claim 1, characterized in that, In step S30, the bifunctional crosslinking agent is SMCC, and the reaction conditions are phosphate buffer solution with pH 7.2-7.6, reacted at room temperature in the dark for 2-4 hours.

6. The preparation method according to claim 1, characterized in that, In step S40, the chemotherapy drug is selected from doxorubicin, cisplatin, paclitaxel or their derivatives; the immune adjuvant is selected from CpG oligodeoxynucleotides, Poly(I:C) or R848; and the enzyme catalyst is selected from glucose oxidase, catalase or lysozyme.

7. The preparation method according to claim 1, characterized in that, In step S40, the covalent connection is carried out by a copper-catalyzed azido-yne cycloaddition reaction or a copper-strain-free azido-yne cycloaddition reaction, and the reaction is carried out at 4°C for 24 hours.

8. The preparation method according to claim 1, characterized in that, In step S50, the acid-sensitive acetal bond is achieved by introducing a 1,3-dioxolane-modified deoxyuridine into the staple chain; the reducing environment-sensitive disulfide bond is formed by introducing thiol groups at the ends of two adjacent staple chains and then oxidizing them with air; the MMP-2 / 9-sensitive polypeptide sequence is embedded in the middle of the staple chain by solid-phase synthesis.

9. The preparation method according to claim 1, characterized in that, In step S60, the cell membrane is extracted from human erythrocytes and purified by hypotonic lysis, differential centrifugation, and ultracentrifugation.

10. A tumor-targeting biomimetic nanomedicine, characterized in that, Prepared by the preparation method according to any one of claims 1-9, the nanomedicine comprises a three-dimensional nanostructure core constructed by DNA origami, wherein the surface of the core is modified with tumor cell-specific aptamers at predetermined sites, and one or more combinations of chemotherapeutic drugs, immune adjuvants or enzyme catalysts are precisely loaded at predetermined sites inside, and the core comprises dynamic structural elements that are sensitive to specific stimuli of the tumor microenvironment.