CN113995732B - Preparation method and application of cancer cell membrane coated drug-loaded zinc-iron oxide nano-composite - Google Patents

Abstract

A preparation method and application of a cancer cell membrane coated drug-loaded zinc-iron oxide nano-composite, which uses mesoporous zinc-iron oxide nano-particles to physically load DNA injury drugs, and then coats the cancer cell membrane on the surface to form the cancer cell membrane coated zinc-iron oxide nano-composite, specifically comprising the following steps: (1) preparing zinc-iron oxide nanoparticles; (2) Preparing a zinc-iron oxide nano-composite loaded with a DNA damage drug; (3) Preparing a cancer cell membrane coated drug-loaded zinc-iron oxide nano-composite; the method is convenient to operate, the method is stable and reliable, the prepared cancer cell membrane coated drug-loaded zinc-iron oxide nano-composite has the advantages of good biocompatibility, small toxic and side effects and the like, can play a role in targeting and activating the cGAS-STING channel to achieve the effect of immunotherapy in the aspect of tumor treatment, is innovation in tumor immunotherapy medicaments, and has huge economic and social benefits.

Description

Preparation method and application of a cancer cell membrane-wrapped drug-loaded zinc-iron oxide nanocomposite

technical field

The invention relates to medicine, in particular to a preparation method and application of a cancer cell membrane-wrapped drug-loaded zinc-iron oxide nanocomposite.

Background technique

Since the 20th century, the environment has been deteriorating day by day, people have been in closer contact with carcinogens, and the incidence of malignant tumors has also increased year by year, seriously affecting human health. In recent years, tumor immunotherapy has achieved great success, and a large number of immune checkpoint inhibitor drugs, including anti-PD-1, anti-PD-L1 and anti-CTLA-4, have been applied clinically. Although these T cell-based immunotherapies have proven to be an effective strategy in a variety of tumors, they are only effective in some patients due to the inefficiency of immune response activation, and non-responsive patients often suffer from non-T cell inflammation The lack of markers associated with the activation of the adaptive antitumor immune response makes this therapy unsatisfactory in the treatment of metastatic tumors. By effectively activating the innate immune response in tumor tissue, it is expected to realize the transformation of tumor from immune non-response to immune response. For this reason, in recent years, the focus of tumor immunotherapy has gradually shifted to innate immunity.

The cGAS-STING pathway is an indispensable innate immune pathway of the body. When an external antigen enters the body, the cytoplasmic DNA binds to cGAS and transmits it to the second messenger cGAMP. The dimerized STING immediately binds to cGAMP, and the conformation changes. Departs from autophagosomes and passes through the endoplasmic reticulum and Golgi apparatus, during which it is ubiquitinated and recruits TBK1 protein, phosphorylates and activates interferon regulatory factors (IRFs) and NF-κB, which can induce type I interferon and other Immune response gene expression. The cGAS-STING pathway plays an important role in the formation of antiviral innate immune response, antitumor immunity and autoimmune diseases. Zinc ions enhance cGAS enzyme activity in vitro and in cells by promoting cGAS-DNA phase separation, promote STING activation, and produce a large amount of type I interferon, so zinc ions play a vital role in the body.

Genotoxic stress caused by DNA-damaging treatments (e.g., reactive oxygen species ROS, DNA-damaging drugs platinum, paclitaxel, etc.) produces chromosomal fragments that are recognized by the nucleic acid sensor cyclic GMP-AMP (cGAMP) synthase (cGAS) . Zinc ions promote the separation of cGAS-DNA and then promote the activation of STING, producing a large amount of type I interferon, and further improving the tumor immune response through synergistic effects.

In order to achieve targeted release of zinc ions and DNA-damaging drugs in tumor cells, mesoporous zinc-iron oxide nanoparticles loaded with DNA-damaging drugs are used to wrap cancer cell membranes. Cancer cell membranes can be degraded in the acidic environment of tumors, and zinc-iron oxides respond to tumor Highly expressed glutathione in cells releases zinc and iron ions (which generate ROS through the Fenton reaction) and drugs to enhance the effect of tumor immunotherapy. Therefore, it is of great significance and value to study a way to activate cGAS-STING pathway to produce type I IFN to achieve tumor immunotherapy.

Contents of the invention

In view of the above situation, in order to overcome the defects of the prior art, the object of the present invention is to provide a preparation method and application of a cancer cell membrane-wrapped drug-loaded zinc-iron oxide nanocomposite, which can effectively solve the drug problem of cancer immunotherapy.

In order to achieve the above object, the technical solution of the present invention is a preparation method of a cancer cell membrane-wrapped drug-loaded zinc-iron oxide nanocomposite, using mesoporous zinc-iron oxide nanoparticles to physically load DNA-damaging drugs, and then wrapping the cancer cell membrane Wrap its surface to form a cancer cell membrane-wrapped zinc-iron oxide nanocomposite, specifically including the following steps:

(1) Preparation of zinc-iron oxide nanoparticles: Dissolve 1-3mmol FeCl ₃ 6H ₂ O and 0.5-1.5mmol ZnCl ₂ in 40mL ethylene glycol to obtain a solution, then add 1.8-5.4g NaAc and 1.0 g polyethylene glycol, stir the mixture vigorously for 30 min, then seal it in a Teflon-lined autoclave (capacity 100 mL), put it in a muffle furnace and seal it, react at 160-200 °C for 12-20 h, and then put Cool the autoclave to room temperature, collect the solid product with a magnet, wash the solid product three times with distilled water and ethanol, respectively, to obtain a sample, and dry the sample in a vacuum oven at 75-85°C for 7.5-8.5 hours to obtain zinc-iron oxide nanoparticles;

(2) Preparation of zinc-iron oxide nanocomposites loaded with DNA-damaging drugs: disperse 2-5 mg of zinc-iron oxide nanoparticles prepared in step (1) in 3-6 mL of PBS buffer at pH 7.4 to form the second One mixed solution; disperse 4-10mg DNA damage drug in 1-2 mL solvent to form the second mixed solution; add the second mixed solution dropwise to the first mixed solution under stirring, stir at room temperature for 24h, then 12000～ Centrifuge at 15,000rpm for 10-20 minutes, and dry at 70-80°C for 5-6 hours in vacuum to obtain a zinc-iron oxide nanocomposite loaded with DNA-damaging drugs;

The DNA damage drug is one of paclitaxel, doxorubicin or platinum drugs;

The solvent is one of ultrapure water, PBS buffer solution with pH=7.4, absolute ethanol, DMSO or formamide;

(3) Preparation of cancer cell membrane-wrapped drug-loaded zinc-iron oxide nanocomposites: Extract the cancer cell membrane by differential centrifugation, centrifuge the cells at 660g for 10min, wash 3 times with PBS of pH 7.4, and resuspend the cell pellet in Perform mechanical disruption in hypotonic lysis buffer, centrifuge at 3200g for 5min, collect the supernatant, and repeat the process, centrifuge the cells again at 3200g for 6min, combine the supernatant, centrifuge at 21000g for 25min at 4°C, and collect the supernatant For the supernatant, centrifuge the supernatant at 45,000 g for 5 min at 4°C in an ultra-high speed centrifuge, discard the supernatant, and quantify the extracted cell membrane fragments with the BCA protein quantification kit. The load prepared in step (2) The zinc-iron oxide nanocomposite of the DNA damage drug was dispersed in PBS with pH 7.4, mixed with the prepared cell membrane at a mass ratio of 1:0.125-4, and the mixture was sonicated for 28-32min in a water-bath sonicator, passed through a polymer The carbonate film is extruded 5-15 times to obtain the product, and the product is centrifuged at 12000-15000 rpm for 10-20 minutes to obtain the cancer cell membrane-wrapped drug-loaded zinc-iron oxide nanocomposite;

The hypotonic lysis buffer is prepared by mixing 20mM Tris-HCl, 10mM KCl, 2mM MgCl ₂ and 1mM PMSF.

Furthermore, the particle size of zinc-iron oxide nanoparticles in the step (1) is 80-160 nm, and the particle size of the cancer cell membrane-wrapped drug-loaded zinc-iron oxide nanocomposite in step (3) is 100-160 nm. 180 nm.

The polycarbonate membrane in the step (3) is a polycarbonate porous membrane with a thickness of 200-400 nm.

Application of the cancer cell membrane-wrapped drug-loaded zinc-iron oxide nanocomposite prepared by the method in the preparation of antitumor drug injections.

Application of the cancer cell membrane-wrapped drug-loaded zinc-iron oxide nanocomposite prepared by the method in the preparation of drugs for enhancing the cGAS-STING immune signal pathway.

Application of the cancer cell membrane-wrapped drug-loaded zinc-iron oxide nanocomposite prepared by the method in the preparation of pH-sensitive, glutathione-responsive mesoporous zinc-iron oxide tumor microenvironment drugs.

The method prepares cancer cell membrane-wrapped drug-loaded zinc-iron oxide nanocomposites and uses them in the preparation of anti-tumor drugs combined with chemotherapy and immunotherapy.

The invention is easy to operate, and the method is stable and reliable. The prepared cancer cell membrane-wrapped drug-loaded zinc-iron oxide nanocomposite has the advantages of good biocompatibility, small toxic and side effects, etc., and can play a role in targeting and activating cGAS- The STING pathway achieves the role of immunotherapy, which is an innovation in tumor immunotherapy drugs, and has huge economic and social benefits.

Detailed ways

The specific implementation of the present invention will be described in detail below in conjunction with the examples.

The present invention can be provided by the following examples in concrete implementation.

Example 1

A method for preparing a cancer cell membrane-wrapped drug-loaded zinc-iron oxide nanocomposite, comprising the following steps:

(1) Preparation of zinc iron oxide nanoparticles: Dissolve 3mmol FeCl ₃ 6H ₂ O and 1.5mmol ZnCl ₂ in 40mL ethylene glycol to obtain a solution, then add 1.8g NaAc and 1.0 g polyethylene glycol, The mixture was vigorously stirred for 30 min, then sealed in a Teflon-lined autoclave, then sealed in a muffle furnace, reacted at 200 ° C for 12 h, then the autoclave was cooled to room temperature, and the solid product was collected with a magnet. Distilled water and ethanol were washed 3 times to obtain a sample, and the sample was dried in a vacuum oven at 75°C for 8.5 hours to obtain zinc-iron oxide nanoparticles;

(2) Preparation of paclitaxel-loaded zinc-iron oxide nanocomposites: disperse 2 mg of zinc-iron oxide nanoparticles prepared in step (1) in 3 mL of PBS buffer at pH 7.4 to form the first mixture; 4 1 mg paclitaxel was dispersed in 1 mL of absolute ethanol to form the second mixed solution; the second mixed solution was added dropwise to the first mixed solution under stirring, stirred at room temperature for 24 hours, then centrifuged at 12000 rpm for 20 minutes, and dried in vacuum at 70°C for 6 hours to obtain the loaded Zinc iron oxide nanocomposite of paclitaxel;

(3) Preparation of cancer cell membrane-wrapped drug-loaded zinc-iron oxide nanocomposites: extract the cancer cell membrane by differential centrifugation, centrifuge the cells at 660g for 10min, wash 3 times with PBS of pH 7.4, and resuspend the cell pellet in a low Perform mechanical destruction in the lysis buffer, centrifuge at 3200g for 5min, collect the supernatant, and repeat the process, centrifuge the cells again at 3200g for 6min, combine the supernatant, centrifuge at 21000g for 25min at 4°C, and collect the supernatant Centrifuge the supernatant at 45,000g for 5min at 4°C in an ultra-high-speed centrifuge, discard the supernatant, and quantify the extracted cell membrane fragments with the BCA protein quantification kit. The loaded paclitaxel prepared in step (2) The zinc-iron oxide nanocomposite was dispersed in PBS with pH 7.4, mixed with the prepared cell membrane at a mass ratio of 1:1, the mixture was sonicated for 28 min in a water-bath sonicator, and extruded 7 times through a polycarbonate membrane. To obtain the product, centrifuge the product at 12,000 rpm for 20 min to obtain the cancer cell membrane-wrapped drug-loaded zinc-iron oxide nanocomposite.

Example 2

A method for preparing a cancer cell membrane-wrapped drug-loaded zinc-iron oxide nanocomposite, comprising the following steps:

(1) Preparation of zinc iron oxide nanoparticles: Dissolve 2mmol FeCl ₃ 6H ₂ O and 1mmol ZnCl ₂ in 40mL ethylene glycol to obtain a solution, then add 3.6g NaAc and 1.0g polyethylene glycol, and The mixture was vigorously stirred for 30 min, then sealed in a Teflon-lined autoclave, sealed in a muffle furnace, and reacted at 180 ° C for 16 h, then the autoclave was cooled to room temperature, and the solid product was collected with a magnet, and the solid product was washed with distilled water Wash with ethanol for 3 times to obtain a sample, and dry the sample in a vacuum oven at 80°C for 7 hours to obtain zinc-iron oxide nanoparticles;

(2) Preparation of zinc-iron oxide nanocomposites loaded with doxorubicin: disperse 4 mg of zinc-iron oxide nanoparticles prepared in step (1) in 5 mL of PBS buffer solution at pH 7.4 to form a first mixed solution; Disperse 7 mg of doxorubicin in 1 mL of ultrapure water to form the second mixed solution; add the second mixed solution dropwise to the first mixed solution with stirring, stir at room temperature for 24 hours, then centrifuge at 13,500 rpm for 15 minutes, and dry in vacuum at 75°C 5.5h, the zinc-iron oxide nanocomposite loaded with doxorubicin was obtained;

(3) Preparation of cancer cell membrane-wrapped drug-loaded zinc-iron oxide nanocomposites: extract the cancer cell membrane by differential centrifugation, centrifuge the cells at 660g for 10min, wash 3 times with PBS of pH 7.4, and resuspend the cell pellet in a low Perform mechanical destruction in the lysis buffer, centrifuge at 3200g for 5min, collect the supernatant, and repeat the process, centrifuge the cells again at 3200g for 6min, combine the supernatant, centrifuge at 21000g for 25min at 4°C, and collect the supernatant Centrifuge the supernatant at 45,000 g for 5 min at 4°C in an ultra-high speed centrifuge, discard the supernatant, and quantify the extracted cell membrane fragments with the BCA protein quantification kit. The zinc-iron oxide nanocomposite of mycin was dispersed in PBS with pH 7.4, mixed with the prepared cell membrane at a mass ratio of 1:2, the mixture was sonicated for 30 min in a water bath sonicator, and extruded through a polycarbonate membrane for 11 Once, the product was obtained, and the product was centrifuged at 13,500 rpm for 15 min to obtain the cancer cell membrane-wrapped drug-loaded zinc-iron oxide nanocomposite.

Example 3

A method for preparing a cancer cell membrane-wrapped drug-loaded zinc-iron oxide nanocomposite, comprising the following steps:

(1) Preparation of zinc iron oxide nanoparticles: Dissolve 1mmol FeCl ₃ 6H ₂ O and 0.5mmol ZnCl ₂ in 40mL ethylene glycol to obtain a solution, then add 5.4g NaAc and 1.0g polyethylene glycol, The mixture was vigorously stirred for 30 min, then sealed in a Teflon-lined autoclave, then sealed in a muffle furnace, reacted at 200 ° C for 12 h, then the autoclave was cooled to room temperature, and the solid product was collected with a magnet. Distilled water and ethanol were washed 3 times to obtain a sample, and the sample was dried in a vacuum oven at 85°C for 7.5 hours to obtain zinc-iron oxide nanoparticles;

(2) Preparation of paclitaxel-loaded zinc-iron oxide nanocomposites: disperse 5 mg of zinc-iron oxide nanoparticles prepared in step (1) in 6 mL of PBS buffer at pH 7.4 to form the first mixture; 10 mg Paclitaxel was dispersed in 2 mL of formamide to form the second mixed solution; the second mixed solution was added dropwise to the first mixed solution under stirring, stirred at room temperature for 24 hours, then centrifuged at 15,000 rpm for 10 minutes, and dried in vacuum at 80°C for 5 hours to obtain loaded paclitaxel Zinc-iron oxide nanocomposites;

(3) Preparation of cancer cell membrane-wrapped drug-loaded zinc-iron oxide nanocomposites: extract the cancer cell membrane by differential centrifugation, centrifuge the cells at 660g for 10min, wash 3 times with PBS of pH 7.4, and resuspend the cell pellet in a low Perform mechanical destruction in the lysis buffer, centrifuge at 3200g for 5min, collect the supernatant, and repeat the process, centrifuge the cells again at 3200g for 6min, combine the supernatant, centrifuge at 21000g for 25min at 4°C, and collect the supernatant Centrifuge the supernatant at 45,000g for 5min at 4°C in an ultra-high-speed centrifuge, discard the supernatant, and quantify the extracted cell membrane fragments with the BCA protein quantification kit. The loaded paclitaxel prepared in step (2) The zinc-iron oxide nanocomposite was dispersed in PBS with pH 7.4, mixed with the prepared cell membrane at a mass ratio of 1:4, and the mixture was sonicated for 32 min in a water bath sonicator, and squeezed 15 times through a polycarbonate membrane. The product is obtained, and the product is centrifuged at 15,000 rpm for 10 minutes to obtain the cancer cell membrane-wrapped drug-loaded zinc-iron oxide nanocomposite.

The preparation method of the present invention is simple, and the tumor site is targeted through the homologous targeting effect of the cancer cell membrane. The expressed glutathione releases zinc ions in response, generates reactive oxygen species, increases cytoplasmic DNA content, strongly activates the intracellular cGAS-STING pathway and then promotes STING activation, produces a large amount of type I interferon, and further improves tumor immunity through synergistic effects answer. Through repeatedly testing, all obtained consistent result, taking embodiment 2 as example, relevant test data are as follows:

1. Characterization test of cancer cell membrane-wrapped drug-loaded zinc-iron oxide nanocomposites:

1. Determination of paclitaxel content in cancer cell membrane-wrapped drug-loaded zinc-iron oxide nanocomposites:

The content of DNA damaging drugs was determined by ultraviolet spectrophotometry at a wavelength of 227nm. Calculate the drug-loading rate of the sample by formula (1), and the drug-loading rate reaches about 38.4%;

Formula 1);

2. Determination of the particle size and potential of the drug-loaded zinc-iron oxide nanocomposite wrapped in the cancer cell membrane:

Take an appropriate amount of cancer cell membrane-wrapped drug-loaded zinc-iron oxide nanocomposite and disperse it in water. The hydrated particle size and potential are measured by Nano-ZS90 laser nanoparticle size analyzer as 157.8nm and -23.8mV, respectively;

3. Transmission electron microscope characterization of cancer cell membrane-wrapped drug-loaded zinc-iron oxide nanocomposites:

Dissolve the drug complex in ultrapure water to prepare a solution with a concentration of 50 μg/mL, drop 1 drop on the ordinary carbon support film, and repeat this operation 5 times after the liquid evaporates, and use a transmission electron microscope (TalosF200S) According to the type shooting, the particle size of the drug complex is 100-180nm.

2. In vitro degradation experiment of cancer cell membrane-wrapped drug-loaded zinc-iron oxide nanocomposites:

The cancer cell membrane-wrapped drug-loaded zinc-iron oxide nanocomposite (CM@ZnFe ₂ O ₄ -PTX) was placed in PBS (pH7.4) buffer, PBS (pH5.4), PBS (pH5.4, containing 10 mM GSH) buffer solution, the concentration was 50μg/mL, and the particle size was detected at 30min, 1h, 2h, and 4h, respectively. The results showed that the particle size of CM@ZnFe ₂ O ₄ -PTX reached about 1000nm after 4 hours, which better indicated that the formulation could be released in a targeted manner in tumor cells.

3. Detection of relevant protein expression in tumor tissue by Western Blotting technology:

Melanoma B16F10 cells were cultured and inoculated subcutaneously in the right hind limb of C57BL/6 mice. When the tumor volume reached 100 mm ³ , the mice were randomly divided into 6 groups, specifically: PBS, PTX , ZnCl ₂ + Six groups of FeCl ₃ , ZnCl ₂ +FeCl ₃ +PTX, CM@ZnFe ₂ O ₄ , CM@ZnFe ₂ O ₄ -PTX were injected into the tail vein, once every other day, for a total of 5 times. The dose of PTX was 4 mg/kg.

The tumor tissue of tumor-bearing mice was extracted, and the protein was lysed with lysate, the protein content was quantified by BCA quantitative method, and the protein expression of type I interferon, pIFR3 and IRF3 was detected, and the normal saline group was compared with other control groups. The preparation can activate the cGAS-STING pathway to produce a large amount of type I interferon, improve tumor immune response and achieve anti-tumor effect.

The present invention has carried out identical experiment to embodiment 1 and 3 by above-mentioned experimental method, has all obtained identical or similar result, no longer enumerates one by one here.

As can be seen from the above experiments, the present invention has the following outstanding beneficial technical effects compared with the prior art:

(1) The cancer cell membrane-wrapped drug-loaded zinc-iron oxide nanocomposite provided by the present invention has good biocompatibility and stability, can physically load DNA-damaging drugs, increase its drug loading, and solve the problem of many fat-soluble drugs. Medication issues; at the same time, the homologous targeting effect of the cancer cell membrane can make the preparation localize to the tumor site, and achieve targeted release under the condition of acidic environment and high expression of GSH;

(2) The DNA damage drugs and iron ions provided by the present invention can break DNA at a low dose and release it into the cytoplasm, the cGAS-STING signaling pathway senses the dsDNA in the cytoplasm, and Zn ²⁺ can strongly enhance the cGAS in the cell - The STING pathway then promotes the activation of STING, produces a large amount of type I interferon, and further improves the tumor immune response through synergistic effects;

(3) The DNA damage drug provided by the present invention can exert a better anti-tumor effect at a low dose, and can avoid adverse side effects in chemotherapy.

The invention is easy to operate, and the method is stable and reliable, and the prepared cancer cell membrane-wrapped drug-loaded zinc-iron oxide nanocomposite has the advantages of good biocompatibility, small toxic and side effects, etc., and can exert GSH and pH responsive positioning release in tumor treatment The drug reaches the tumor cells, activates the cGAS-STING pathway in the cells at the same time to improve the immune response, and realizes the synergistic effect of tumor chemotherapy and immune combination, which improves the therapeutic effect of tumors. It is an innovation in tumor treatment drugs and has huge economic and social benefits. .

Claims (5)

1. A preparation method of a cancer cell membrane coated drug-loaded zinc-iron oxide nano-composite is characterized in that mesoporous zinc-iron oxide nano-particles are used for physically loading DNA injury drugs, and then cancer cell membranes are coated on the surfaces of the drug-loaded zinc-iron oxide nano-composite to form the cancer cell membrane coated zinc-iron oxide nano-composite, and the preparation method specifically comprises the following steps:

(1) Preparing zinc-iron oxide nanoparticles: 1 to 3mmol FeCl ₃ ·6H ₂ O and 0.5-1.5 mmol ZnCl ₂ Dissolving in 40mL of ethylene glycol to obtain a solution, then adding 1.8-5.4 g of NaAc and 1.0g of polyethylene glycol, vigorously stirring the mixture for 30min, then sealing in a Teflon-lined autoclave, then placing in a muffle furnace for sealing, reacting for 12-20 h at 160-200 ℃, then cooling the autoclave to room temperature, collecting a solid product by using a magnet, washing the solid product with distilled water and ethanol for 3 times respectively to obtain a sample, and drying the sample in a vacuum oven at 75-85 ℃ for 7.5-8.5h to obtain zinc-iron oxide nanoparticles; the particle size of the zinc-iron oxide nano particles is 80-160 nm;

(2) Preparing a zinc-iron oxide nano-composite loaded with a DNA damage drug: dispersing 2-5 mg of zinc-iron oxide nanoparticles prepared in the step (1) in 3-6 mL of PBS buffer solution with pH of 7.4 to form a first mixed solution; dispersing 4-10 mg of DNA damage medicine in 1-2 mL solvent to form a second mixed solution; dropwise adding the second mixed solution into the first mixed solution under stirring, stirring at room temperature for 24 hours, centrifuging at 12000-15000 rpm for 10-20 minutes, and drying at 70-80 ℃ for 5-6 hours in vacuum to obtain a zinc-iron oxide nano-composite loaded with a DNA damage drug;

the DNA damage medicine is one of paclitaxel and doxorubicin;

the solvent is one of ultrapure water, PBS buffer solution with pH=7.4, absolute ethyl alcohol, DMSO or formamide;

(3) Preparing a cancer cell membrane coated drug-loaded zinc-iron oxide nano-composite: extracting cancer cell membrane by differential centrifugation, centrifuging the cells at 660g for 10min, washing 3 times with PBS of pH7.4, mechanically destroying the cell pellet, centrifuging at 3200g for 5min, collecting supernatant, repeating the process, centrifuging the cells again at 3200g for 6min, combining the supernatants, centrifuging at 21000g for 25min at 4 ℃, collecting supernatant, centrifuging the supernatant at 45000g for 5min at 4 ℃ in a super high speed centrifuge, discarding the supernatant, quantifying the extracted cell membrane fragments with BCA protein quantification kit, dispersing the DNA-damaging drug-loaded zinc-iron oxide nanocomposite prepared in step (2) in PBS of pH7.4, and mixing with the prepared cell membrane at 1: mixing the materials according to the mass ratio of 0.125-4, performing ultrasonic treatment on the mixture in a water bath ultrasonic instrument for 28-32min, extruding the mixture through a polycarbonate membrane for 5-15 times to obtain a product, and centrifuging the product at 12000-15000 rpm for 10-20 min to obtain the cancer cell membrane coated drug-loaded zinc-iron oxide nano-composite; the particle size of the cell membrane coated drug-loaded zinc-iron oxide nano-composite is 100-180 nm;

the hypotonic lysis buffer is prepared from 20mM Tris-HCl, 10mM KCl and 2mM MgCl ₂ And 1mM PMSF.

2. The method for preparing the cancer cell membrane-encapsulated drug-loaded zinc-iron oxide nanocomposite according to claim 1, comprising the steps of:

(1) Preparing zinc-iron oxide nanoparticles: 3mmol FeCl ₃ ·6H ₂ O and 1.5mmol ZnCl ₂ Dissolving in 40mL of ethylene glycol to obtain a solution, then adding 1.8g of NaAc and 1.0g of polyethylene glycol, vigorously stirring the mixture for 30min, then sealing in a Teflon-lined autoclave, then sealing in a muffle furnace, reacting at 200 ℃ for 12h, then cooling the autoclave to room temperature, collecting solid products by using a magnet, washing the solid products with distilled water and ethanol for 3 times respectively to obtain a sample, and drying the sample in a vacuum oven at 75 ℃ for 8.5h to obtain zinc-iron oxide nanoparticles;

(2) Preparing taxol-loaded zinc-iron oxide nano-composite: dispersing 2mg of zinc-iron oxide nanoparticles prepared in the step (1) in 3mL of PBS buffer solution with pH of 7.4 to form a first mixed solution; dispersing 4mg taxol in 1mL absolute ethanol to form a second mixed solution; dropwise adding the second mixed solution into the first mixed solution under stirring, stirring at room temperature for 24 hours, centrifuging at 12000rpm for 20 minutes, and drying at 70 ℃ in vacuum for 6 hours to obtain a taxol-loaded zinc-iron oxide nano-composite;

(3) Preparing a cancer cell membrane coated drug-loaded zinc-iron oxide nano-composite: extracting cancer cell membrane by differential centrifugation, centrifuging the cells at 660g for 10min, washing 3 times with PBS of pH7.4, mechanically disrupting the cell pellet by re-suspending in hypotonic lysis buffer, centrifuging at 3200g for 5min, collecting supernatant, repeating the process, centrifuging the cells again at 3200g for 6min, combining the supernatants, centrifuging at 21000g for 25min at 4 ℃, collecting supernatant, centrifuging the supernatant at 45000g for 5min at 4 ℃ in ultra-high speed centrifuge, discarding the supernatant, quantifying the extracted cell membrane fragments with BCA protein quantification kit, dispersing the paclitaxel-loaded zinc-iron oxide nanocomposite prepared in step (2) in PBS of pH7.4, and mixing the prepared cell membrane with 1:1, carrying out ultrasonic treatment on the mixture for 28min in a water bath ultrasonic instrument, extruding the mixture through a polycarbonate membrane for 7 times to obtain a product, and centrifuging the product at 12000rpm for 20min to obtain the cancer cell membrane coated drug-loaded zinc-iron oxide nano-composite.

3. The method for preparing the cancer cell membrane-encapsulated drug-loaded zinc-iron oxide nanocomposite according to claim 1, comprising the steps of:

(1) Preparing zinc-iron oxide nanoparticles: 2mmol FeCl ₃ ·6H ₂ O and 1mmol ZnCl ₂ Dissolving in 40mL of ethylene glycol to obtain a solution, then adding 3.6g of NaAc and 1.0g of polyethylene glycol, vigorously stirring the mixture for 30min, then sealing in a Teflon-lined autoclave, then sealing in a muffle furnace, reacting at 180 ℃ for 16h, then cooling the autoclave to room temperature, collecting solid products by using a magnet, washing the solid products with distilled water and ethanol for 3 times respectively to obtain a sample, and drying the sample in a vacuum oven at 80 ℃ for 7h to obtain zinc-iron oxide nanoparticles;

(2) Preparing a zinc-iron oxide nano-composite loaded with doxorubicin: dispersing 4mg of zinc-iron oxide nanoparticles prepared in the step (1) in 5mL of PBS buffer solution with pH of 7.4 to form a first mixed solution; dispersing 7mg of doxorubicin in 1mL of ultrapure water to form a second mixed solution; dropwise adding the second mixed solution into the first mixed solution under stirring, stirring at room temperature for 24 hours, centrifuging at 13500rpm for 15 minutes, and drying at 75 ℃ for 5.5 hours under vacuum to obtain an doxorubicin-loaded zinc-iron oxide nano-composite;

(3) Preparing a cancer cell membrane coated drug-loaded zinc-iron oxide nano-composite: extracting cancer cell membrane by differential centrifugation, centrifuging the cells at 660g for 10min, washing 3 times with PBS of pH7.4, mechanically disrupting the cell pellet by re-suspending in hypotonic lysis buffer, centrifuging at 3200g for 5min, collecting supernatant, repeating the process, centrifuging the cells again at 3200g for 6min, combining the supernatants, centrifuging at 21000g for 25min at 4 ℃, collecting supernatant, centrifuging the supernatant at 45000g for 5min at 4 ℃ in a super high speed centrifuge, discarding the supernatant, quantifying the extracted cell membrane fragments with BCA protein quantification kit, dispersing the doxorubicin-loaded zinc-iron oxide nanocomposite prepared in step (2) in PBS of pH7.4, and mixing the prepared cell membrane with 1:2, carrying out ultrasonic treatment on the mixture for 30min in a water bath ultrasonic instrument, extruding the mixture through a polycarbonate membrane for 11 times to obtain a product, and centrifuging the product at 13500rpm for 15 min to obtain the cancer cell membrane coated drug-loaded zinc-iron oxide nano-composite.

4. The method for preparing the cancer cell membrane-encapsulated drug-loaded zinc-iron oxide nanocomposite according to claim 1, comprising the steps of:

(1) Preparing zinc-iron oxide nanoparticles: 1mmol FeCl ₃ ·6H ₂ O and 0.5mmol ZnCl ₂ Dissolving in 40mL of ethylene glycol to obtain a solution, then adding 5.4g of NaAc and 1.0g of polyethylene glycol, vigorously stirring the mixture for 30min, then sealing in a Teflon-lined autoclave, then sealing in a muffle furnace, reacting at 200 ℃ for 12h, then cooling the autoclave to room temperature, collecting solid products by using a magnet, washing the solid products with distilled water and ethanol for 3 times respectively to obtain a sample, and drying the sample in a vacuum oven at 85 ℃ for 7.5h to obtain zinc-iron oxide nanoparticles;

(2) Preparing taxol-loaded zinc-iron oxide nano-composite: dispersing 5mg of zinc-iron oxide nanoparticles prepared in the step (1) in 6mL of PBS buffer solution with pH of 7.4 to form a first mixed solution; dispersing 10mg of paclitaxel in 2 mL formamide to form a second mixed solution; dropwise adding the second mixed solution into the first mixed solution under stirring, stirring at room temperature for 24 hours, centrifuging at 15000rpm for 10 minutes, and drying at 80 ℃ for 5 hours in vacuum to obtain a taxol-loaded zinc-iron oxide nano-composite;

(3) Preparing a cancer cell membrane coated drug-loaded zinc-iron oxide nano-composite: extracting cancer cell membrane by differential centrifugation, centrifuging the cells at 660g for 10min, washing 3 times with PBS of pH7.4, mechanically disrupting the cell pellet by re-suspending in hypotonic lysis buffer, centrifuging at 3200g for 5min, collecting supernatant, repeating the process, centrifuging the cells again at 3200g for 6min, combining the supernatants, centrifuging at 21000g for 25min at 4 ℃, collecting supernatant, centrifuging the supernatant at 45000g for 5min at 4 ℃ in ultra-high speed centrifuge, discarding the supernatant, quantifying the extracted cell membrane fragments with BCA protein quantification kit, dispersing the paclitaxel-loaded zinc-iron oxide nanocomposite prepared in step (2) in PBS of pH7.4, and mixing the prepared cell membrane with 1:4, carrying out ultrasonic treatment on the mixture for 32min in a water bath ultrasonic instrument, extruding the mixture through a polycarbonate membrane for 15 times to obtain a product, and centrifuging the product at 15000rpm for 10min to obtain the cancer cell membrane coated drug-loaded zinc-iron oxide nano-composite.

5. The method for preparing a cancer cell membrane-coated drug-loaded zinc-iron oxide nanocomposite according to any one of claims 1 to 4, wherein the polycarbonate membrane in the step (3) is a polycarbonate porous membrane of 200 to 400 nm.