BiVO4 and black phosphorus composite material rich in oxygen vacancies as well as preparation method and application of BiVO4 and black phosphorus composite material
By preparing the composite material of BiVO4 nanoparticles and black phosphorus nanosheets rich in oxygen vacancies, using X-ray excitation to generate O2, combined with photothermal treatment, the problem of limited effect of radiodynamic therapy in the microenvironment of hypoxic tumors is solved, and the effect of multi-mode synergistic anti-tumor treatment is improved.
Patent Information
- Application Number
- CN202510723827.3
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-06-01
- Publication Date
- 2025-09-02
AI Technical Summary
The existing radiodynamic therapy has limited effect in the hypoxic tumor microenvironment, making it difficult to effectively overcome the tumor hypoxia problem, resulting in treatment failure, recurrence and metastasis.
The composite material of BiVO4 nanoparticles and black phosphorus nanosheets rich in oxygen are prepared, and heterojunctions are formed through electrostatic adsorption, and in situ O2 is generated by X-ray excitation, combined with photothermal treatment to achieve multi-mode synergistic anti-tumor treatment.
It enhances the oxygen supply in the tumor hypoxia area, improves the effect of radiodynamic therapy, and enhances the ablation of X-ray-insensitive cancer cells through photothermal therapy, improving the overall efficiency and selectivity of tumor treatment.
Smart Images
Figure CN120571014A_ABST
Abstract
Description
Technical Field
[0001] The present invention belongs to the field of biomedical material preparation; specifically relates to a composite material of BiVO4 nanoparticles and black phosphorus nanosheets rich in oxygen vacancies and a preparation method thereof; the present invention also relates to the application of the composite material in enhancing tumor radiodynamic therapy. Background Art
[0002] Cancer remains the leading cause of death worldwide, driving the continuous development and exploration of innovative treatment strategies. Radiodynamic therapy (RDT) organically combines traditional radiotherapy (RT) and photodynamic therapy (PDT) and is a promising method for treating deep tumors. RDT overcomes the inherent limitations of PDT (such as shallow tissue penetration) by utilizing radiation energy to activate local photosensitizers to target the generation of reactive oxygen species (ROS), while solving the problem of inefficient energy deposition of traditional radiotherapy at the tumor site. However, the unique microenvironment of solid tumors, such as severe hypoxia, greatly restricts the effectiveness of RDT.
[0003] Hypoxia is a common phenomenon in the tumor microenvironment (TME), often caused by insufficient angiogenesis during rapid tumor growth. This reduces systemic sensitivity to radiation, making cancer cells more resistant to RT / RDT than normal cells. Therefore, hypoxia in solid tumors is a fundamental cause of treatment failure, recurrence, invasion, and metastasis. Hypoxic tumor regions are key therapeutic targets, and overcoming hypoxia is a major challenge in anti-tumor efforts. Various strategies have been developed to regulate tumor hypoxia, such as delivering exogenous O2, reducing cellular O2 consumption, and catalyzing the generation of O2 from endogenous hydrogen peroxide. However, these strategies are limited by poor material stability and insufficient O2 supply. Therefore, there is a need to explore more advanced and effective strategies to address hypoxia. Inspired by numerous reports on photocatalytic water splitting, induced holes with sufficient oxidation potential can oxidize H2O to generate O2. Compared to traditional photodynamic therapy, RDT is triggered by irradiation with highly tissue-penetrating X-rays. X-rays can excite wide-bandgap photosensitizers, generating electrons and holes in the conduction band and valence band, respectively. The holes can react with H2O to form O2. Therefore, the strategy of intracellular water splitting using X-ray-responsive photosensitizers is expected to achieve controlled O2 release and targeted delivery to alleviate hypoxia in deep tumor tissues.
[0004] Bismuth vanadate (BiVO4) is a promising photocatalytic water splitting material. It has been widely used in photocatalytic water splitting due to its intrinsic advantages such as suitable band gap (2.5eV), deep valence band position, and light effective mass of electrons and holes. In addition, BiVO4 has good biosafety and stability, with a high oral lethal dose value (>5000mg / kg), and has been classified as a non-toxic material. In addition, oxygen vacancies (O V ) can enhance the separation of electrons and holes and promote the decomposition of water and the generation of O2. Oxygen vacancies, acting as positive charge centers, enhance the adsorption of water molecules on the photosensitizer surface, promoting the catalytic generation of ROS and O2. The in situ generated O2 can effectively alleviate tumor hypoxia and enhance the therapeutic efficacy of RD-RDT.
[0005] In addition, combining RDT with other treatment methods such as photothermal therapy (PTT) is a feasible method to improve treatment efficiency. PTT can effectively ablate cancer cells that are insensitive to X-rays, increase blood flow in the tumor, and thus enhance the oxygen conditions in the tumor. Black phosphorus (BP, also known as two-dimensional black phosphorus nanosheets in the present invention) is a two-dimensional material that has attracted much attention in recent years. It has unique electrical and optical properties, such as high carrier mobility and switching ratio, high anisotropy and photothermal conversion performance. Phosphorus is an essential element in organisms. As a nanomaterial composed of a single phosphorus element, black phosphorus has good biological activity and biocompatibility. Therefore, black phosphorus has unparalleled advantages in the biomedical field, especially in the multimodal synergistic treatment of tumors. Although the application of black phosphorus nanocarriers in tumor photothermal and photothermal-chemotherapy treatment has achieved certain research results, the construction of multifunctional nanocomposites based on black phosphorus nanosheets for multimodal synergistic treatment of cancer has yet to be developed. Summary of the Invention
[0006] In view of this, the purpose of the present invention is to provide a composite material of BiVO4 nanoparticles and black phosphorus nanosheets rich in oxygen vacancies and a preparation method thereof, and the obtained BiVO4 / black phosphorus nanosheet composite material has the photothermal, radiotherapy and radiodynamic synergistic treatment functions of X-ray induced in situ O2 production.
[0007] The objectives of the present invention can be achieved through the following technical scheme: a method for preparing a multimodal synergistic anti-tumor biomedical material based on a composite material of BiVO4 nanoparticles rich in oxygen vacancies and black phosphorus nanosheets, characterized in that: based on a two-dimensional black phosphorus nanomaterial, well-dispersed BiVO4 nanoparticles are combined with the two-dimensional black phosphorus nanomaterial through electrostatic adsorption to form a composite, thereby forming a combined anti-tumor material with X-ray induced in situ O2 production for synergistic radiotherapy, radiodynamic therapy and photothermal therapy.
[0008] Furthermore, the preparation method is characterized in that the specific steps are as follows:
[0009] (1) Preparation of BiVO4 with good dispersion:
[0010] Bismuth salt, vanadate, and sodium dodecyl sulfate (SDS) were dissolved in nitric acid solution and stirred vigorously to obtain a clear orange solution. An appropriate amount of deionized water (DI) was added to the prepared orange solution and the pH was adjusted to 1 to obtain a final solution. The final solution was transferred to a polytetrafluoroethylene-lined autoclave and maintained at 150°C for 10 hours. The solution was then naturally cooled to room temperature. The yellow product was collected and washed several times with deionized water and ethanol to remove ions and residues, finally obtaining BiVO4 with good dispersion.
[0011] (2) Preparation of polycyclic aromatic hydrocarbons (PAH) modified black phosphorus nanomaterials:
[0012] The two-dimensional black phosphorus nanosheets ultrasonically exfoliated in a nitrogen-methylpyrrolidone solution are centrifuged at 8000-10000 rpm / min, washed with alcohol, washed with deoxygenated water, and dispersed in water. Polycyclic aromatic hydrocarbons (PAH) and the above-mentioned two-dimensional black phosphorus nanosheets (BP) are stirred and mixed at room temperature in a certain ratio, and then centrifuged and washed to remove the supernatant to obtain PAH-modified BP nanosheets.
[0013] (3) Preparation of composite photodynamic anti-tumor biomedical materials:
[0014] The PAH-modified BP nanosheets prepared in step (2) and the well-dispersed BiVO4 prepared in step (1) were stirred and mixed in a certain proportion at room temperature, and the supernatant was removed by centrifugation to successfully prepare the phototherapy anti-tumor composite nanomaterial.
[0015] Furthermore, the preparation method is characterized in that: the mass ratio of bismuth ions to vanadium ions in step (1) is (0.9-1):(1-1.1); the amount of sodium lauryl sulfate is 0.1 g; the amount of nitric acid is 6.33 ml, the concentration is 68 wt%; and the amount of deionized water is 93.67 ml.
[0016] Furthermore, the preparation method is characterized in that: in step (2), the mass ratio of PAH to BP is (0.8-1.2):(1.8-2.2); the stirring mixing time at room temperature in step (2) is 4-8 hours; in step (3), the mass ratio of PAH-modified BP nanosheets to BiVO4 is (1-6):(0.8-1.2); and the stirring mixing time at room temperature in step (3) is 8-15 hours.
[0017] Furthermore, the preparation method is characterized in that: based on two-dimensional black phosphorus nanomaterials, an X-ray induced in situ O2 production anti-tumor biomedical material is prepared by electrostatic adsorption method, and after stirring at room temperature in the dark in a deoxygenated aqueous solution system, the material is centrifuged and washed to obtain a multi-modal synergistic anti-tumor biomedical material prepared by the electrostatic adsorption method.
[0018] The multimodal synergistic anti-tumor biomedical material based on the composite material of BiVO4 nanoparticles rich in oxygen vacancies and black phosphorus nanosheets prepared by the above preparation method of the present invention can be used in the combined treatment of tumors by radiotherapy, X-ray photodynamic therapy, and photothermal therapy.
[0019] The present invention provides a method for preparing a multimodal synergistic anti-tumor biomedical material based on a composite material of BiVO4 nanoparticles rich in oxygen vacancies and black phosphorus nanosheets, comprising the following specific steps:
[0020] (1) Preparation of the above-mentioned well-dispersed BiVO4:
[0021] 0.4852g Bi2(NO3)3·5H2O, 0.1169g NH4VO3, and 0.1000g sodium dodecyl sulfate (SDS) were weighed and dissolved in 6.33ml of 68% nitric acid solution. The mixture was stirred vigorously to obtain a clear orange solution. An appropriate amount of deionized (DI) water was added to the prepared solution to adjust the pH to 1. The final 100ml solution was transferred to a 150ml Teflon-lined autoclave, maintained at 150°C for 10 hours, and then cooled naturally to room temperature. The yellow product was collected and washed several times with deionized water and ethanol to remove ions and possible residues, resulting in well-dispersed BiVO4.
[0022] (2) Preparation of polycyclic aromatic hydrocarbons (PAH) modified black phosphorus nanomaterials:
[0023] Black phosphorus nanosheets, ultrasonically exfoliated in a nitrogen-methylpyrrolidone solution, were collected by centrifugation at 8,000-10,000 rpm. The nanosheets were washed with alcohol, deoxygenated water, and then dispersed in water. Polycyclic aromatic hydrocarbons (PAH) and black phosphorus (BP) were stirred at room temperature for 6 hours at a mass ratio of 1:2. The PAH-modified BP nanosheets (NPs) were then centrifuged and the supernatant removed.
[0024] (3) Preparation of composite photodynamic anti-tumor biomedical materials:
[0025] Polycyclic aromatic hydrocarbon (PAH)-modified black phosphorus nanomaterials (PAH-modified BP NPs) and BiVO4 were stirred at room temperature in a mass ratio of 3:1 for 12 hours, and the supernatant was removed by centrifugation to successfully prepare phototherapy anti-tumor composite nanomaterials.
[0026] Furthermore, the bismuth salt described in step (1) is a soluble bismuth salt; preferably one of bismuth chloride, bismuth carbonate and bismuth nitrate pentahydrate.
[0027] Furthermore, the vanadate described in step (1) is a soluble vanadate; preferably one of ammonium metavanadate, sodium vanadate and potassium vanadate.
[0028] Furthermore, in step (1), the mass ratio of bismuth ions to vanadium ions is (0.9-1):(1-1.1).
[0029] Furthermore, the amount of sodium lauryl sulfate used in step (1) is 0.1 g.
[0030] Furthermore, in step (1), the amount of nitric acid is 6.33 ml.
[0031] Furthermore, in step (1), the distilled water (also referred to as deionized water in the present invention) is 93.67 ml
[0032] Furthermore, in step (2), the mass ratio of PAH to two-dimensional black phosphorus nanosheets (BP) is (0.8-1.2):(1.8-2.2).
[0033] Furthermore, the stirring time at room temperature in step (2) is 4 to 8 hours.
[0034] Furthermore, in step (3), the mass ratio of PAH-modified BP NPs to BiVO4 is (1-6):(0.8-1.2).
[0035] Furthermore, the stirring time at room temperature in step (3) is 8 to 15 hours.
[0036] The benefits of the present invention are:
[0037] 1. In the present invention, the preparation method of BiVO4 nanoparticles is simple, the raw materials are cheap and easily available, the prepared BiVO4 is hydrophilic, well dispersed in the aqueous solution system, and not prone to coagulation, and the prepared BiVO4 has abundant oxygen vacancies. On the one hand, oxygen vacancies can regulate the electronic structure of the material and promote the generation of reactive oxygen species, such as hydroxyl radicals (·OH), singlet oxygen ( 1 O2). These ROS can attack the DNA, lipids, and proteins of cancer cells, causing irreversible oxidative damage and inducing apoptosis or necrosis. On the other hand, oxygen vacancies can improve the hypoxic state of the tumor microenvironment. The rapid proliferation of tumor cells leads to vascular abnormalities and localized hypoxia. Oxygen vacancies, as positively charged centers, can enhance the adsorption of water molecules on the photosensitizer surface, strengthen the separation of electrons and holes, and promote the catalytic generation of ROS and O2, thereby improving the efficacy of multimodal synergistic tumor treatments such as RD-RDT.
[0038] 2. In the present invention, PAH is used to modify black phosphorus nanosheets. A layer of PAH is wrapped on the surface of BP nanosheets to protect BPNPs and avoid oxidation and degradation of BPNPs in aqueous solution and air.
[0039] 3. In the present invention, due to its high atomic number and strong X-ray absorption, BiVO4 nanoparticles and black phosphorus form a Type I heterojunction. When irradiated with X-rays, the BiVO4 nanoparticles absorb the X-rays and directly transfer part of the energy to the black phosphorus nanosheets. The excited black phosphorus nanosheets generate singlet excitons through strong exciton interactions. The singlet excitons transfer energy to triplet oxygen, thereby forming singlet oxygen. Simultaneously, the BiVO4 nanoparticles and black phosphorus form a heterojunction, enhancing the separation of photogenerated electrons and holes, thereby further enhancing the effectiveness of radiodynamic therapy.
[0040] In the present invention, both BiVO4 nanoparticles and black phosphorus nanosheets have excellent photothermal properties. After forming a heterojunction, they further enhance the photothermal performance. At 808nm, 1W / cm 2 Under near-infrared light irradiation, after 10 minutes of illumination, the temperature of the BiVO4-BP (100μg / ml) solution can be increased from 26.1°C to 73.2°C, demonstrating super strong photothermal performance. Its superior photothermal performance can further enhance the effects of radiotherapy, photodynamic therapy, and chemodynamic therapy. In summary, the BiVO4 / black phosphorus nanosheet composite material prepared by the present invention can realize the combined treatment of tumors with radiotherapy, X-ray photodynamic therapy, and photothermal therapy. This tumor microenvironment-responsive composite nanomaterial has high biocompatibility, safety, and specificity, and has great potential for application in tumor treatment. BRIEF DESCRIPTION OF THE DRAWINGS
[0041] Figure 1 This is a transmission electron microscope image of BiVO4 with good dispersion prepared in a specific embodiment of the present invention.
[0042] Figure 2 This is a transmission electron microscope image of the BiVO4 / black phosphorus nanosheet composite material in a specific embodiment of the present invention.
[0043] Figure 3 This is a graph showing the in-situ oxygen production performance of the BiVO4 / black phosphorus nanosheet composite material under X-rays in a specific embodiment of the present invention. The graph shows the oxygen production curves of water, BP and BiVO4-BP solution under X-ray irradiation.
[0044] Figure 4a This is an absorption spectrum of the photodynamic properties of five substances in the BiVO4 / black phosphorus nanosheet composite material under X-ray irradiation in a specific embodiment of the present invention.
[0045] Figure 4b This is a photodynamic performance curve of the four substances of the BiVO4 / black phosphorus nanosheet composite material under X-ray irradiation in a specific embodiment of the present invention.
[0046] Figure 5 This is a photothermal performance diagram of the BiVO4 / black phosphorus nanosheet composite material in a specific embodiment of the present invention, which shows the temperature change curves of water, BP and BiVO4-BP solution under near-infrared light irradiation. DETAILED DESCRIPTION
[0047] Example 1
[0048] Preparation of well-dispersed bismuth vanadate (BiVO4):
[0049] 0.4852g Bi2(NO3)3·5H2O, 0.1169g NH4VO3, and 0.1000g sodium dodecyl sulfate (SDS) were weighed and dissolved in 6.33ml of nitric acid solution (68wt%) and stirred vigorously to obtain a clear orange solution. An appropriate amount of deionized water (DI) was added to the prepared orange solution, and the pH was adjusted to 1 to obtain a final 100ml solution. The final 100ml solution was transferred to a 150ml polytetrafluoroethylene-lined autoclave, maintained at 150°C for 10 hours, and then naturally cooled to room temperature. The yellow product was collected and washed with deionized water and ethanol three times to remove ions and residues in the yellow product, and finally, BiVO4 with good dispersion was obtained.
[0050] The microstructure of BiVO4 with good dispersion is as follows Figure 1 As shown, the particles are well dispersed and uniform in size, with a size of approximately 150 nm.
[0051] Example 2
[0052] Preparation of polycyclic aromatic hydrocarbons (PAH) modified black phosphorus nanomaterials:
[0053] The two-dimensional black phosphorus nanosheets ultrasonically exfoliated in nitrogen-methyl pyrrolidone solvent were divided into 50 ml centrifuge tubes, centrifuged at 8000 rpm for 20 minutes, and the supernatant was collected. The supernatant was centrifuged again at 10000 rpm for 20 minutes. The precipitate was collected, washed 3 times with anhydrous ethanol, and washed 3 times with deoxygenated water to obtain two-dimensional black phosphorus nanosheets, namely black phosphorus (BP). Polycyclic aromatic hydrocarbons (PAH) and two-dimensional black phosphorus nanosheets (BP) were stirred at room temperature for 6 hours in a mass ratio of 1:2, and centrifuged and washed to obtain PAH-modified BP NPs (abbreviated as BP NPs, also referred to as polycyclic aromatic hydrocarbons (PAH)-modified BP nanosheets in the present invention). BP NPs were finally dispersed in deoxygenated water and stored in the dark at 4°C for later use.
[0054] Example 3
[0055] The BiVO4 prepared in Example 1 was slowly added dropwise to 30 mL of 100 ppm PAH-modified BP NPs solution prepared in Example 2 at a mass ratio of 1:3. The mixture was stirred at room temperature for 12 h, and the supernatant was removed by centrifugation. Thus, a multimodal synergistic anti-tumor composite nanomaterial (hereinafter referred to as BiVO4-BP) was successfully prepared. The microscopic morphology of the BiVO4-BP is shown in FIG. Figure 2 Thermocouple was used to monitor the 808nm, 1W / cm 2 The temperature change of BiVO4 (100 μg / mL) and two-dimensional black phosphorus nanosheets BP (100 μg / mL) solution under near-infrared light irradiation is plotted, as shown in the figure. Figure 5 As shown in the figure, under the same illumination conditions, the temperature change of BiVO4-BP solution was greater than that of BP solution when BiVO4-BP and BP solutions were of equal concentration. After 10 minutes of illumination, the temperature of BiVO4-BP (100 μg / mL) solution increased from 22.9°C to 72.3°C, a temperature increase of 47.1°C, while the temperature of BP solution alone increased by only 43.5°C.
[0056] Example 4
[0057] In order to study the oxygen production performance of the material BiVO4-BP, a dissolved oxygen meter was used to detect its oxygen production. Figure 3 As shown. The curve of BiVO4-BP (100μg / mL) has a fast oxygen production rate and high oxygen production. The BiVO4-BP material contains a large number of oxygen vacancies. These oxygen vacancies can efficiently adsorb H2O2 molecules, making it easier for them to decompose and produce oxygen. At the same time, they are beneficial to the separation of photogenerated carriers, reduce recombination, and continuously provide electrons and other reaction conditions for the oxygen production reaction, promoting rapid oxygen production and high output. The H2O+X+5mm H2O2 system basically does not produce oxygen, indicating that it is difficult to produce a significant oxygen production reaction without oxygen vacancies, highlighting the key role of active oxygen vacancies in the material in promoting the oxygen production reaction.
[0058] In order to investigate the significantly enhanced ROS generation of BiVO4-BP nanocomposites, 9,10-anthryl-bis(methylene)dimalonic acid (ABDA) and methylene blue (MB) were used as detectors, respectively. 1 Indicator of O2 and OH. Figure 4a As shown in the figure, compared with the blank control water, the absorbance of BiVO4-BP was significantly reduced under X-ray (70kV, 100μA) irradiation, while the absorbance of BiVO4 and BP did not change significantly when exposed to X-rays compared with the control water. This shows that BiVO4-BP has excellent 1O2 production ability. BiVO4-BP nanocomposites have abundant oxygen vacancies, and oxygen vacancies, as positive charge centers, can enhance the adsorption of water molecules on the surface of the photosensitizer, enhance the separation of electrons and holes, and promote the catalytic generation of ROS and O2, generating more 1 O2, so the absorbance of BiVO4-BP group added with H2O2 decreased more than that of BiVO4-BP group. Figure 4b As shown in the figure, the absorbance changes of methylene blue (MB) at 660nm after X-ray irradiation of different sample groups. Compared with the blank control group, BiVO4-BP can effectively generate hydroxyl radicals under X-ray irradiation, and the absorbance value of MB is significantly reduced.
Claims
1. A method for preparing a multimodal synergistic anti-tumor biomedical material based on a composite material of BiVO4 nanoparticles rich in oxygen vacancies and black phosphorus nanosheets, characterized by: Based on two-dimensional black phosphorus nanomaterials, well-dispersed BiVO4 nanoparticles combine with two-dimensional black phosphorus nanomaterials through electrostatic adsorption to form a complex, thereby forming a combined anti-tumor material with synergistic radiotherapy, radiodynamic therapy and photothermal therapy with X-ray induced in situ O2 production.
2. The preparation method according to claim 1, wherein: The specific steps are as follows: (1) Preparation of BiVO4 with good dispersion: Bismuth salt, vanadate, and sodium dodecyl sulfate (SDS) were dissolved in nitric acid solution and stirred vigorously to obtain a clear orange solution. An appropriate amount of deionized water (DI) was added to the prepared orange solution and the pH was adjusted to 1 to obtain a final solution. The final solution was transferred to a polytetrafluoroethylene-lined autoclave and maintained at 150°C for 10 hours. The solution was then cooled naturally to room temperature. The yellow product was collected and washed several times with deionized water and ethanol to remove ions and residues, finally obtaining BiVO4 with good dispersion. (2) Preparation of polycyclic aromatic hydrocarbons (PAH) modified black phosphorus nanomaterials: The two-dimensional black phosphorus nanosheets ultrasonically exfoliated in a nitrogen-methylpyrrolidone solution were centrifuged at 8000-10000 rpm / min, washed with alcohol, washed with deoxygenated water, and dispersed in water. Polycyclic aromatic hydrocarbons (PAH) and the above-mentioned two-dimensional black phosphorus nanosheets (BP) were stirred and mixed at room temperature in a certain ratio, and then centrifuged and washed to remove the supernatant to obtain PAH-modified BP nanosheets. (3) Preparation of composite photodynamic anti-tumor biomedical materials: The PAH-modified BP nanosheets prepared in step (2) and the well-dispersed BiVO4 prepared in step (1) were stirred and mixed in a certain proportion at room temperature, and the supernatant was removed by centrifugation and washing, thereby successfully preparing the optical therapy anti-tumor composite nanomaterial.
3. The preparation method according to claim 2, wherein: The mass ratio of bismuth ions to vanadium ions in step (1) is (0.9-1):(1-1.1); the amount of sodium lauryl sulfate used is 0.1 g; the amount of nitric acid is 6.33 ml, with a concentration of 68 wt%; and the amount of deionized water is 93.67 ml.
4. The preparation method according to claim 2, wherein: The mass ratio of PAH to BP in step (2) is (0.8~1.2):(1.8~2.2); the stirring mixing time at room temperature in step (2) is 4~8 h; the mass ratio of PAH-modified BP nanosheets to BiVO4 in step (3) is (1~6):(0.8~1.2); the stirring mixing time at room temperature in step (3) is 8~15 h.
5. The preparation method according to any one of claims 1 to 4, characterized in that: Based on two-dimensional black phosphorus nanomaterials, the electrostatic adsorption method was used to prepare X-ray induced in situ O2 production anti-tumor biomedical materials. After stirring in a deoxygenated aqueous solution system at room temperature in the dark, the materials were centrifuged and washed to obtain multimodal synergistic anti-tumor biomedical materials prepared by the electrostatic adsorption method.
6. The multimodal synergistic anti-tumor biomedical material based on a composite material of BiVO4 nanoparticles rich in oxygen vacancies and black phosphorus nanosheets prepared by the preparation method according to any one of claims 1 to 4 can be used in the combined treatment of tumors by radiotherapy, X-ray photodynamic therapy, and photothermal therapy.