A fusion film-wrapped composite nanodelivery system, and a preparation method and application thereof

Abstract

This invention discloses a composite nanodelivery system encapsulated in a fusion membrane, its preparation method, and its applications. The nanodelivery system comprises a Ti3C2 / TiO2 / CuInS2 composite material, oxaliplatin loaded thereon, and a fusion membrane encapsulating the outer layer; the fusion membrane is formed by the fusion of Fusobacterium nucleatum extravesicles and M1 macrophage membranes. This invention also discloses a method for preparing the nanodelivery system, including the steps of preparing the Ti3C2 / TiO2 / CuInS2 composite material, preparing the fusion membrane, loading oxaliplatin, and encapsulating it in the fusion membrane. The nanodelivery system prepared by this invention exhibits pH-responsive drug release characteristics, generating H2S in the tumor microenvironment and H2 under light irradiation, while also possessing photocatalytic activity. This invention combines chemotherapy, photoelectrocatalytic therapy, and the regulation of multiple active substances, and can be used to prepare drugs for treating malignant tumors of the digestive system.

Description

Technical Field

[0001] This invention belongs to the fields of biomedicine and nanomaterials technology, specifically relating to a composite nanodelivery system with fused membrane encapsulation, its preparation method, and its application. Background Technology

[0002] Oxaliplatin (OXa), as a first-line chemotherapy drug, plays an important role in the treatment of gastrointestinal malignancies such as colorectal cancer and gastric cancer. However, its clinical application still faces bottlenecks such as insufficient targeted delivery capability, significant toxic side effects, and easy development of tumor drug resistance. After intravenous administration, the drug is randomly distributed throughout the body, with extremely low effective accumulation at the tumor lesion site. Most of the drug is taken up by normal organs, which not only reduces the therapeutic efficacy but also easily causes severe peripheral neurotoxicity, gastrointestinal reactions, and bone marrow suppression, seriously affecting the patient's treatment prognosis and quality of life.

[0003] To overcome the aforementioned clinical challenges, the research and industry sectors are committed to developing novel nanomedicine delivery systems. Through carrier modification and functional enhancement, they aim to achieve precise delivery and efficient release of oxaliplatin, and explore multimodal synergistic treatment strategies to improve efficacy and reduce drug resistance.

[0004] MXenes, a class of two-dimensional transition metal carbide / nitride nanomaterials, have become preferred carriers for nanomedicine delivery systems due to their excellent hydrophilicity, high specific surface area, and abundant surface functional groups. Among them, titanium carbide (Ti3C2) is the most widely studied novel two-dimensional nanomaterial in the MXenes family. Its surface can be functionalized with hydroxyl groups to acquire a negative charge, facilitating the adsorption of drug molecules for efficient delivery. Simultaneously, due to its localized surface plasmon resonance (LSPR) effect, it possesses excellent light absorption and photothermal conversion capabilities, which can assist in photothermal therapy. Furthermore, TiO2, as a classic photocatalytic material, can generate reactive oxygen species under light irradiation to achieve photocatalytic killing; CuInS2 quantum dots possess excellent photoelectric properties and copper ion (Cu... 2+ The combined application of these functional materials has become an important research direction for synergistic drug delivery using nanoparticles. Furthermore, biomimetic membrane coating technology, by mimicking the biological characteristics of natural cell membranes, can effectively enhance the in vivo stealth and biocompatibility of nanocarriers, reduce clearance by the mononuclear phagocyte system (MPS), and prolong the in vivo circulation time of the carrier, thus ensuring long-term, precise drug delivery.

[0005] Despite some progress in the aforementioned areas, existing nanomedicine delivery systems still have significant shortcomings in design and function, making it difficult to meet the clinical needs of "precise targeting, low toxicity, and synergistic multi-effect therapy." Regarding functional integration, existing Ti3C2-based drug delivery systems mostly focus on single chemotherapy or simple photothermal / photocatalytic synergy, failing to organically integrate the photoelectric conduction advantages of Ti3C2, the photocatalytic performance of TiO2, and the photoelectric response and copper ion release capabilities of CuInS2 quantum dots. They also cannot simultaneously achieve the controlled release of H2S and H2, making it difficult to form a multi-effect synergistic therapeutic system of "photocatalysis - copper ion-mediated copper death - H2S / H2 microenvironment regulation - chemotherapy." In terms of biomimetic membrane design, existing technologies mostly use single cell membrane components, resulting in limited targeting and immune escape capabilities. Furthermore, membrane encapsulation can easily affect the photoelectric signal transmission and release of active substances from the carrier. In terms of system synergy, existing drug delivery systems all suffer from problems such as narrow photoelectric response range, uncontrollable release of active substances, and insufficient biocompatibility and stability, and have not formed a linkage mechanism of "photoelectric signal triggering - precise drug release - synchronous release of active substances - synergistic killing".

[0006] In summary, there are currently no reports on technologies that synergistically design Ti3C2 / TiO2 / CuInS2 composite materials with fusion membranes, and organically combine copper ion release, H2S release, H2 release with photoelectric capabilities and chemotherapeutic drug delivery. Therefore, developing a nanodelivery system that combines precise targeting, efficient drug loading, photoelectric response, controlled release of multiple active substances, and multi-effect synergistic therapy has become a crucial technical challenge in the field of cancer treatment. Summary of the Invention

[0007] To overcome the shortcomings of existing technologies and achieve multi-effect synergistic therapy involving chemotherapy, photocatalytic therapy, pH-responsive precise drug release, and the controlled release of multiple active substances such as H2S and H2, this invention provides a nano-delivery system based on a fusion membrane-encapsulated Ti3C2 / TiO2 / CuInS2-loaded oxaliplatin, its preparation method, and its application.

[0008] To achieve the above-mentioned technical objectives, the present invention adopts the following technical solution: A first aspect of the present invention provides a nanodelivery system based on a fused film-encapsulated Ti3C2 / TiO2 / CuInS2-loaded oxaliplatin, comprising: The Ti3C2 / TiO2 / CuInS2 composite material is composed of a single layer of Ti3C2, TiO2 nanoparticles grown in situ on the surface of Ti3C2 sheets, and CuIn2 quantum dots loaded on the surface of Ti3C2 / TiO2. Oxaliplatin loaded on the Ti3C2 / TiO2 / CuInS2 composite material; and A fusion film encapsulating the exterior of the Ti3C2 / TiO2 / CuInS2 composite material; The fusion membrane is formed by the fusion of external vesicles derived from Fusobacterium nucleatum and the membrane of M1 macrophages.

[0009] In the technical solution of this invention, monolayer Ti3C2 serves as the substrate of the composite material, possessing a high specific surface area and abundant surface functional groups, which is beneficial for efficient drug loading. TiO2 nanoparticles are firmly bonded to the surface of Ti3C2 sheets through in-situ growth, endowing the composite material with photocatalytic properties. CuInS2 quantum dots are uniformly loaded on the Ti3C2 / TiO2 surface, further enhancing the photoelectric response capability and copper ion release potential of the composite material. The synergistic effect of these three components enables the Ti3C2 / TiO2 / CuInS2 composite material to possess excellent photoelectric properties, photocatalytic activity, and pH responsiveness.

[0010] In the technical solution of this invention, the fusion membrane is formed by fusing external vesicles derived from Fusobacterium nucleatum with the membrane of M1 macrophages. Fusobacterium nucleatum external vesicles have good tumor targeting properties, while the M1 macrophage membrane has immune activation function and immune escape capability. The fusion membrane formed by the fusion of these two components can effectively improve the biocompatibility, targeting, and in vivo circulation time of the nanodelivery system.

[0011] Furthermore, the mass ratio of the outer vesicles derived from Fusobacterium nucleatum to the M1 macrophage membrane in the fusion membrane is 1:0.5 to 1:2. Within this range, the fusion membrane can maintain good membrane structural integrity and functional synergy, achieving the dual functions of targeting and immune evasion.

[0012] Furthermore, the cumulative drug release rate of the nanodelivery system is higher at pH 5.5–6.5 than at pH 7.2–7.4. The tumor microenvironment is typically weakly acidic (pH 5.5–6.5), while the normal physiological environment has a pH of 7.2–7.4. This invention utilizes this pH difference to enable precise controlled drug release at the tumor site, while releasing less in normal tissues, thereby reducing toxic side effects.

[0013] Furthermore, the nanodelivery system generates H2S within the tumor microenvironment. As a gaseous signaling molecule, H2S can modulate the tumor microenvironment, improve tumor hypoxia, and synergistically enhance the effects of chemotherapy and photocatalytic therapy.

[0014] Furthermore, the nanodelivery system generates H2 under light irradiation. H2 has selective antioxidant properties, which can reduce oxidative stress damage during treatment. At the same time, H2 itself also has certain anti-tumor activity, further enhancing the therapeutic effect.

[0015] A second aspect of the present invention provides a method for preparing the nanodelivery system described in the first aspect of the present invention, comprising the following steps: (1) Preparation of Ti3C2 / TiO2 / CuInS2 composite material; (2) Preparation of fusion membrane: The outer vesicles and M1 macrophage membranes derived from Fusobacterium nucleatum were extracted separately, mixed and subjected to sonication and extrusion to obtain the fusion membrane; (3) Oxaliplatin was loaded onto Ti3C2 / TiO2 / CuInS2 composite material to obtain TTC / OXa composite system; (4) The fusion membrane obtained in step (2) is mixed with the TTC / OXa composite system obtained in step (3), and subjected to ultrasonic and extrusion treatment to obtain a nanodelivery system encapsulated by the fusion membrane.

[0016] Furthermore, the preparation of the Ti3C2 / TiO2 / CuInS2 composite material in step (1) includes: preparing a monolayer Ti3C2 by hydrofluoric acid etching and tetramethylammonium hydroxide intercalation exfoliation; growing TiO2 in situ on the surface of the monolayer Ti3C2 by hydrothermal reaction to obtain Ti3C2 / TiO2; mixing Ti3C2 / TiO2 with CuInS2 quantum dots in an equal volume ratio, and then ultrasonically treating to obtain the Ti3C2 / TiO2 / CuInS2 composite material. This preparation method can ensure that TiO2 grows uniformly in situ on the surface of Ti3C2 sheets and that CuInS2 quantum dots are uniformly loaded, forming a stable heterostructure.

[0017] Furthermore, the preparation of the fusion membrane in step (2) includes: extracting external vesicles from the *Fusobacterium nucleatum* culture medium by ultracentrifugation; extracting the M1 macrophage membrane by induced polarization, cell lysis, and ultracentrifugation; mixing the external vesicles from *Fusobacterium nucleatum* with the M1 macrophage membrane at a mass ratio of 1:0.5 to 1:2, and then extruding them sequentially through 800 nm, 400 nm, and 200 nm polycarbonate membranes after sonication to obtain the fusion membrane. By sequentially extruding through polycarbonate membranes of different pore sizes, the two membrane components can be fully fused to form a fusion membrane vesicle with uniform particle size and stable structure.

[0018] Furthermore, the ultrasonic treatment time in step (4) is 30 minutes, and the extrusion treatment uses an 800 nm porous polycarbonate film. These conditions ensure that the fusion film is uniformly coated on the surface of the TTC / OXa composite system, forming a complete core-shell structure.

[0019] A third aspect of the present invention provides the application of the nanodelivery system described in the first aspect of the invention in the preparation of medicaments for treating malignant tumors of the digestive system. These malignant tumors include, but are not limited to, colorectal cancer and gastric cancer. The nanodelivery system of the present invention, through the synergistic effects of chemotherapy, photocatalytic therapy, and the regulation of multiple active substances such as H2S and H2, can effectively inhibit tumor growth, reduce the toxic side effects of chemotherapy drugs, and improve treatment efficacy and patient quality of life.

[0020] The beneficial effects of this invention are as follows: Compared with existing technologies, the nanodelivery system provided by this invention has a stable structure and uniform morphology, exhibits high drug loading capacity for oxaliplatin, and possesses pH-responsive drug release characteristics, enabling precise controlled release of drugs in the microacidic environment of tumors and reducing toxic side effects on normal tissues. This system also possesses excellent photoelectric properties and photocatalytic activity, mediating photocatalytic therapy under light irradiation. Simultaneously, the system can generate H2S in the tumor microenvironment and H2 under light irradiation, achieving controlled release of multiple active substances. This invention organically combines chemotherapy, photocatalytic therapy, copper ion-mediated copper death, and H2S / H2 microenvironment regulation to form a multi-mechanism synergistic therapeutic system that can effectively inhibit tumor growth, reduce drug resistance, and improve treatment efficacy. Attached Figure Description

[0021] Figure 1 Transmission electron microscopy images and elemental distribution diagrams of HMV@TTC / OXa prepared in Example 1 of this invention.

[0022] Figure 2 The image shows the dynamic light scattering particle size distribution of HMV@TTC / OXa prepared in Example 1 of this invention.

[0023] Figure 3 The image shows the zeta potential diagrams of the HMV@TTC / OXa prepared in Example 1 of this invention and the control sample.

[0024] Figure 4 The image shows the ultraviolet absorption spectrum of TTC / OXa prepared in Example 1 of this invention.

[0025] Figure 5 The image shows the drug release curves of TTC / OXa prepared in Example 1 of this invention under different pH conditions.

[0026] Figure 6 This is a comparison of the drug release curves of TTC / OXa and Ti3C2 / OXa prepared in Example 1 of the present invention.

[0027] Figure 7 This is a comparison of the ultraviolet absorption spectra of TTC prepared in Example 1 of the present invention and pure Ti3C2.

[0028] Figure 8 The transient photocurrent response diagram of the TTC prepared in Example 1 of this invention is shown.

[0029] Figure 9 The H2S release curves of TTC prepared in Example 1 of this invention under different pH conditions are shown.

[0030] Figure 10 The H2 release curves of TTC / OXa prepared in Example 1 of this invention at different times are shown. Detailed Implementation

[0031] The present invention is further illustrated below with reference to specific embodiments. These embodiments are for illustrative purposes only and should not be construed as limiting the invention. Those skilled in the art will understand that various changes, modifications, substitutions, and variations can be made to these embodiments without departing from the principles and spirit of the invention. The scope of the invention is defined by the claims and their equivalents. Experimental methods in the following embodiments that do not specify specific conditions are generally performed under conventional conditions or according to the manufacturer's recommendations; the reagents and materials mentioned, unless otherwise specified, are commercially available.

[0032] Example 1: Preparation of a Ti3C2 / TiO2 / CuInS2-loaded oxaliplatin nanodelivery system encapsulated in a fusion film (1) Preparation of monolayer Ti3C2 Preparation of multilayer Ti3C2: 10 mL of hydrofluoric acid (HF) with a concentration of not less than 40% was measured in a polytetrafluoroethylene container as an etchant. 1 g of Ti3AlC2 powder was slowly added to the acid solution in batches. The reaction vessel was placed in a 55℃ constant temperature water bath and stirred continuously for 2 hours, with gentle shaking every 30 minutes. After the reaction was complete, the mixture was centrifuged at 3500 rpm / min, and the bottom precipitate was collected. The precipitate was washed repeatedly with deionized water until the pH of the supernatant was close to neutral (approximately 6), thus obtaining the multilayer Ti3C2 material.

[0033] Preparation of monolayer Ti3C2: 1 g of multilayer Ti3C2 powder was dispersed in 10 mL of tetramethylammonium hydroxide (TMAH, 25%) solution and stirred continuously at room temperature for 24 hours. Residual intercalating agent was removed by repeated washing and centrifugation. The precipitate was redispersed in deionized water and sonicated. Centrifugation was performed at 3500 rpm, and the supernatant containing the monolayer was collected. The centrifuged precipitate was redispersed, and the sonication and centrifugation steps were repeated, with a total sonication time of 4 hours. All supernatants were collected and freeze-dried to obtain monolayer Ti3C2 powder.

[0034] (2) Preparation of CuInS2 quantum dots In a reaction vessel, 0.095 g of cuprous iodide (CuI), 0.146 g of indium(III) acetate, 10 mL of 1-octadecene, and 1 mL of oleic acid (OA) were added sequentially and thoroughly dissolved to prepare a metal precursor solution. 5 mL of 1-dodecathiol was then injected as a sulfur source. Under nitrogen protection, the mixture was degassed at 130 °C for 30 minutes, followed by degassing at 10 °C·min under a N2 atmosphere. -1 The temperature was increased to 220℃ at a constant rate, and the reaction was maintained at that temperature for 5 minutes. After the reaction was completed, the mixture was allowed to cool naturally. The crude product was then centrifuged and washed three times using a hexane / ethanol solvent system and dried under vacuum at 60℃ to obtain CuInS2 quantum dots.

[0035] (3) Synthesis of Ti3C2-TiO2 Synthesis of TiO2: Solution A was prepared by mixing 5 mL of tetrabutyl titanate and 5 mL of anhydrous ethanol; solution B was prepared by mixing 20 mL of anhydrous ethanol, 5 mL of deionized water, and 1 mL of nitric acid. Solution A was slowly added dropwise to solution B under continuous stirring, and the mixture was stirred at room temperature for 1 hour to obtain a precursor solution. The precursor solution was transferred to a polytetrafluoroethylene-lined high-pressure reactor and reacted in an oven at 160 °C for 6 hours. After natural cooling, the precipitate was collected, dried at 60 °C for 24 hours, and then calcined in a muffle furnace at 450-550 °C for 2 hours to obtain TiO2 nanoparticles.

[0036] Synthesis of Ti3C2-TiO2: 400 mg of monolayer Ti3C2 MXene and 823.5 mg of sodium fluoroborate (NaBF4) were co-dispersed in 75 mL of 1 M hydrochloric acid (HCl) solution. After stirring thoroughly for 20 minutes, the mixture was transferred to a 100 mL polytetrafluoroethylene-lined high-pressure reactor and sealed. The reactor was then subjected to hydrothermal reaction at 180 °C for 24 h. After natural cooling, the black solid product was collected by centrifugation, washed three times repeatedly with ultrapure water and anhydrous ethanol, and dried in a vacuum drying oven at 60 °C to obtain Ti3C2-TiO2 powder.

[0037] (4) Synthesis of Ti3C2-TiO2-CuInS2 (TTC) 1 mg / mL CuInS2 quantum dots and 1 mg / mL Ti3C2-TiO2 dispersion were mixed evenly in equal volume ratio, and the mixture was ultrasonically treated in a low-temperature water bath for 6-8 hours. The mixture was then stirred overnight at room temperature to obtain a homogeneous TTC material.

[0038] (5) Extraction of exovesicles derived from Fusobacterium nucleatum Cultures of *Fusobacterium nucleatum* grown to the logarithmic growth phase were centrifuged at 8000 g for 20 min at 4 °C to remove bacterial cells. The supernatant was collected and filtered through a 0.22 μm microporous membrane to ensure the removal of residual bacteria and cell debris. The filtrate was concentrated 10-fold using a 100 kDa ultrafiltration tube. Subsequently, the concentrate was ultracentrifuged at 150,000 g at 4 °C for 120 min, and the coarse *Fusobacterium nucleatum*-derived exovesicles at the bottom were collected. The precipitate was resuspended twice in sterile PBS and then ultracentrifuged again (150,000 g, 4 °C, 120 min) to collect pure *Fusobacterium nucleatum*-derived exovesicles. The final precipitate was resuspended in an appropriate amount of sterile PBS, and the concentration was determined using a BCA protein quantification kit. After aliquoting as needed, the precipitate was stored at -80 °C for long-term storage.

[0039] (6) Extraction of M1 macrophage membrane First, cells were induced to polarize for 24 h with 100 ng / mL LPS and 50 ng / mL IFN-γ. Then, approximately 1 × 10⁻⁶ cells were collected. 7 M1 macrophages were used to preserve membrane protein activity, avoiding the use of trypsin throughout the process. Cells were washed twice with ice-cold™ buffer (pH 7.5). Cells were resuspended in 50 mL buffer and pre-cooled at 4°C. During the physical lysis phase, cells were lysed sequentially by tissue homogenization (6 rpm, 5 min) and probe sonication. Finally, the crude extract was purified using ultracentrifugation (150,000 g, 4°C, 1 h), and the resulting vesicle pellet was collected and stored at 4°C for later use.

[0040] (7) Preparation of fusion membrane The concentrations of proteins on the outer vesicles of *Fusobacterium nucleatum* and the membranes of M1 macrophages were determined using a BCA protein assay kit. Then, the collected outer vesicles of *Fusobacterium nucleatum* and the membranes of M1 macrophages were dissolved in sterile PBS at a 1:1 membrane weight ratio and mixed. The mixture was then sonicated at 4°C for 10 minutes to homogenize. The homogenized solution was then co-extruded using a liposome extruder, sequentially extruded through 800 nm, 400 nm, and 200 nm polycarbonate membranes 11 times to obtain a fusion membrane, which was then stored at -80°C for long-term preservation.

[0041] (8) Preparation of Ti3C2-TiO2-CuInS2 / OXa (HMV@TTC / OXa) encapsulated in fusion film The obtained fusion membrane was mixed with an equal amount of TTC / OXa, and sonicated at low temperature for 30 min. The mixture was then co-extruded multiple times with an 800 nm porous polycarbonate film using a micro extruder to obtain the HMV@TTC / OXa nanodelivery system.

[0042] Example 2 Morphology characterization and performance testing of nanodelivery systems 1. Morphological characterization and stability testing The morphology of HMV@TTC / OXa was observed using transmission electron microscopy (TEM), and the results showed that ( Figure 1 The material is coated with a transparent film approximately 10–20 nm thick, exhibiting typical cell membrane characteristics, indicating that the fusion membrane has been successfully and completely coated onto the material surface. Elemental mapping shows that C and O signals are widely distributed with clear edge contours, corresponding to the Ti3C2 substrate and biomembrane components; the overlap of Cu and S signals confirms the presence of CuInS2 quantum dots; the detection of Pt signals confirms the successful loading of the anticancer drug OXa; and the uniform distribution of P, as a characteristic element of the cell membrane phospholipid bilayer, further corroborates the effectiveness of membrane encapsulation from a chemical composition perspective. These results demonstrate that the Ti3C2-TiO2-CuInS2 (TTC) prepared in Example 1 possesses a uniform multi-component heterogeneous structure, forming structurally stable nanovesicles after being coated with the fusion membrane.

[0043] Dynamic light scattering (DLS) test results show that ( Figure 2 The particle size of HMV@TTC / OXa is concentrated around 280 nm, with a relatively narrow distribution. Zeta potential test results show that... Figure 3 The surface potential of the resulting hybrid membrane vesicle structure stabilizes at approximately -14 mV, which is highly consistent with the electrical characteristics of a typical cell membrane, indicating that the fusion membrane was successfully encapsulated and the system has good stability.

[0044] 2. Drug loading capacity test The drug loading rate of OXa was determined by ultraviolet spectrophotometry. The results showed that ( Figure 4 The drug loading rate of TTC / OXa reached 6.18%, indicating that the special structure of the TTC composite material provides abundant drug binding sites and has good loading capacity for OXa.

[0045] 3. pH-responsive drug release test TTC / OXa was placed in release media at pH 5.5 (simulating the tumor microenvironment) and pH 7.4 (simulating the normal physiological environment), respectively, and the cumulative drug release rate at different time points was measured. The results showed ( Figure 5 At pH 5.5, the cumulative release rate exceeded 80% after 25 hours, while it was only about 40% at pH 7.4. This indicates that the system has obvious pH-responsive drug release characteristics and can achieve precise controlled release of drugs in the slightly acidic environment of tumors.

[0046] Further comparison of drug release capabilities between TTC / OXa and Ti3C2 / OXa was conducted. Results showed ( Figure 6At the end of the 24-hour experiment, the cumulative release percentage of TTC / OXa reached approximately 47%, significantly better than that of the Ti3C2 / OXa group. This indicates that the in-situ growth of TiO2 and CuInS2 between MXene sheets weakens the strong electrostatic binding of the carrier to drug molecules, optimizes the drug diffusion kinetics, and achieves more complete drug release.

[0047] 4. Photocatalytic performance test The light absorption characteristics of TTC and pure Ti3C2 were determined by ultraviolet-visible absorption spectroscopy. The results showed that ( Figure 7 The absorption range of TTC extends from the ultraviolet to the visible light region (approximately 350-650 nm), and its light absorption capacity is significantly better than that of pure Ti3C2. This indicates that the TTC support has excellent light absorption characteristics and can effectively extend the photoresponse range.

[0048] The photoelectric properties of the material were evaluated using transient photocurrent response testing. The results showed that ( Figure 8 The TTC exhibits excellent photoelectric response characteristics, stable photocurrent output, and superior cycle stability. This indicates that the material's photogenerated electron-hole pairs can be effectively separated and transported, possessing excellent photoelectric properties. Under illumination, it can effectively generate therapeutically active substances and mediate photocatalytic therapy.

[0049] 5. H2S and H2 release capacity test H2S release test: TTC was placed under weakly acidic conditions at pH 6.5, and the amount of H2S released was measured. The results showed ( Figure 9 H2S release peaked around the 3rd hour, approaching 100 μM. This indicates that TTC can generate H2S in the tumor microenvironment, providing additional therapeutic benefits for tumor treatment.

[0050] H2 release test: The H2 release capacity of TTC / OXa was measured under near-infrared light irradiation. The results showed ( Figure 10 The material can continuously release H2 within 24 hours, with a final concentration of nearly 100 μM. This indicates that the material has good H2 generation capacity, which can further synergistically enhance the therapeutic effect.

[0051] It should be noted that the above embodiments can be freely combined as needed, and the above description is only for understanding the method and core idea of ​​the present invention. It should be pointed out that those skilled in the art can make several improvements and modifications to the present invention without departing from the principles of the invention, and these improvements and modifications will also fall within the protection scope of the claims of the present invention.

Claims

1. A nanodelivery system based on fused membrane-encapsulated Ti3C2 / TiO2 / CuInS2 loaded with oxaliplatin, characterized in that, include: The Ti3C2 / TiO2 / CuInS2 composite material is composed of a single layer of Ti3C2, TiO2 nanoparticles grown in situ on the surface of Ti3C2 sheets, and CuIn2 quantum dots loaded on the surface of Ti3C2 / TiO2. Oxaliplatin loaded on the Ti3C2 / TiO2 / CuInS2 composite material; and A fusion film encapsulating the exterior of the Ti3C2 / TiO2 / CuInS2 composite material; The fusion membrane is formed by the fusion of external vesicles derived from Fusobacterium nucleatum and the membrane of M1 macrophages.

2. The nanodelivery system according to claim 1, characterized in that, The mass ratio of the external vesicles derived from Fusobacterium nucleatum to the M1 macrophage membrane in the fusion membrane is 1:0.5 to 1:

2.

3. The nanodelivery system according to claim 1, characterized in that, The nanodelivery system exhibits a higher cumulative drug release rate at pH 5.5–6.5 than at pH 7.2–7.

4.

4. The nanodelivery system according to claim 1, characterized in that, The nanodelivery system generates H2S in the tumor microenvironment.

5. The nanodelivery system according to claim 1, characterized in that, The nanodelivery system generates H2 under light irradiation.

6. A method for preparing the nanodelivery system according to any one of claims 1 to 5, characterized in that, Includes the following steps: (1) Preparation of Ti3C2 / TiO2 / CuInS2 composite material; (2) Preparation of fusion membrane: The outer vesicles and M1 macrophage membranes derived from Fusobacterium nucleatum were extracted separately, mixed and subjected to sonication and extrusion to obtain the fusion membrane; (3) Oxaliplatin was loaded onto Ti3C2 / TiO2 / CuInS2 composite material to obtain TTC / OXa composite system; (4) The fusion membrane obtained in step (2) is mixed with the TTC / OXa composite system obtained in step (3), and subjected to ultrasonic and extrusion treatment to obtain a nanodelivery system encapsulated by the fusion membrane.

7. The method according to claim 6, characterized in that, The preparation of the Ti3C2 / TiO2 / CuInS2 composite material in step (1) includes: Monolayer Ti3C2 was prepared by hydrofluoric acid etching and tetramethylammonium hydroxide intercalation stripping. TiO2 was grown in situ on the surface of a monolayer Ti3C2 by hydrothermal reaction to obtain Ti3C2 / TiO2; Ti3C2 / TiO2 and CuInS2 quantum dots were mixed in equal volume ratios and then ultrasonically treated to obtain Ti3C2 / TiO2 / CuInS2 composite material.

8. The method according to claim 6, characterized in that, The preparation of the fusion membrane in step (2) includes: Exovesicles were extracted from the culture medium of *Fusobacterium nucleatum* by ultracentrifugation. M1 macrophage membranes were extracted by induced polarization, cell lysis, and ultracentrifugation. The outer vesicles derived from Fusobacterium nucleatum were mixed with the membrane of M1 macrophages at a mass ratio of 1:0.5 to 1:2, and after sonication, they were extruded sequentially through 800 nm, 400 nm, and 200 nm polycarbonate membranes to obtain the fusion membrane.

9. The method according to claim 6, characterized in that, The ultrasonic treatment time in step (4) is 30 minutes, and the extrusion treatment uses an 800 nm porous polycarbonate film.

10. The use of the nanodelivery system according to any one of claims 1 to 5 in the preparation of a medicament for treating malignant tumors of the digestive system.

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