A hole-rich molybdenum oxide nanosheet with near-infrared photocatalytic performance and its preparation method and application

Abstract

The present invention belongs to the technical field of nanomaterials, and specifically relates to a hole-rich molybdenum oxide nanosheet with near-infrared photocatalytic performance, and a preparation method and application thereof, wherein a molybdenum raw material is dispersed in anhydrous methanol, and hydrogen peroxide is added under an ice bath to form a molybdenum precursor, and then a hole-rich molybdenum oxide nanosheet is obtained by a hydrothermal method, and then triphenylphosphine modification and ultrasonic dispersion are performed to synthesize a monodisperse hole-rich molybdenum oxide nanosheet with mitochondrial targeting. The molybdenum oxide nanosheet of the present invention can be used as a photocatalyst for tumor mitochondrial targeted therapy.

Description

Technical Field

[0001] The invention belongs to the technical field of nanomaterials, and in particular relates to a method for producing hole-rich molybdenum oxide nanosheets with near-infrared photocatalytic performance. Background Art

[0002] In recent years, the field of nanochemistry has achieved remarkable progress, leading to the development of a series of nanocatalysts. These nanocatalysts, including nanozymes, photocatalysts, and electrocatalysts, have attracted widespread attention due to their potential applications in biomedical science, especially in disease treatment. Among them, photocatalysts use light energy to drive chemical transformations, providing unprecedented opportunities to regulate biochemical processes in the body, thereby opening up new avenues for therapeutic intervention. One of the main advantages of using nanophotocatalysts in medical treatment is that they are able to achieve high selectivity and efficiency in catalytic reactions. Unlike traditional treatments that may lack specificity and cause adverse side effects, nanophotocatalysts can precisely target biomolecules or pathways involved in disease progression. This targeted approach can not only improve the efficacy of treatments, but also minimize collateral damage to healthy tissues, thereby improving the overall safety of treatment options.

[0003] The properties required of photocatalytic materials include biocompatibility and stability, target specificity, strong photocatalytic activity, etc. However, few photocatalytic materials currently studied can fully meet these required properties, so it is necessary to develop new photocatalytic materials. Summary of the invention

[0004] The present invention mainly provides a mitochondrial-targeted, monodisperse, hole-rich molybdenum oxide nanosheet with near-infrared photocatalytic performance, as well as a preparation method of the nanosheet and its application in tumor treatment:

[0005] A hole-rich molybdenum oxide nanosheet with near-infrared photocatalytic performance is triphenylphosphine-modified molybdenum oxide; the diameter of the molybdenum oxide nanosheet is less than 100nm, the thickness is less than 10nm, and the light absorption wavelength range is 200-2000nm.

[0006] A method for preparing the above-mentioned hole-rich molybdenum oxide nanosheets with near-infrared photocatalytic performance comprises the following steps:

[0007] (1) using metal molybdenum powder as a raw material, dispersing it in methanol, adding a hydrogen peroxide solution under ice bath conditions, and preparing a molybdenum precursor solution after sufficient mixing;

[0008] (2) subjecting the molybdenum precursor solution to a hydrothermal reaction at 120-200° C. for 12 hours; cooling naturally to room temperature, washing with ethanol and drying to obtain molybdenum oxide nanosheets;

[0009] (3) The molybdenum oxide nanosheets are modified with triphenylphosphine to obtain a nanostructured carbon nanosheet.

[0010] Furthermore, the concentration of the molybdenum powder in methanol in step (1) is 5 to 20 mg / mL.

[0011] Furthermore, the concentration of hydrogen peroxide added in step (1) in the system is 1% to 8%.

[0012] Further, the step of triphenylphosphine modification comprises:

[0013] a. Dispersing molybdenum oxide nanosheets in toluene to form a uniform suspension of 15 to 25 mg / mL; adding 3-aminopropyltriethoxysilane to the suspension, and then reflux reacting at 100 to 120° C. for 20 to 28 hours under the protection of an argon atmosphere; after the reaction, collecting the precipitate by centrifugation and washing it with ethanol to remove residual reactants, and drying to obtain the product;

[0014] b. Ultrasonic dispersion of the product in water to obtain a dispersion of 0.8-1.2 mg / mL, and reaction with active ester-polyethylene glycol-maleimide under weak alkalinity for 2.5-3.5 h, centrifugation to collect the precipitate and wash it thoroughly with water;

[0015] c. Disperse the obtained precipitate in water, adjust the pH of the system to neutral, add mercaptopropyltriphenylphosphine, mix and react for 1.8 to 2.2 hours, centrifuge and wash with water three times, collect the precipitate, and obtain the product.

[0016] Furthermore, the mass ratio of the molybdenum oxide nanosheets to 3-aminopropyltriethoxysilane in step a is 1:3-4.

[0017] Furthermore, the mass ratio of the product in step b to active ester-polyethylene glycol-maleimide is 1:4-6; the mass ratio of the product in step b to mercaptopropyltriphenylphosphine is 1:1.8-2.2.

[0018] Furthermore, the molecular weight of the active ester-polyethylene glycol-maleimide in step b is 1800-2200 Da.

[0019] Furthermore, the weak alkalinity in step b is pH=7.0-8.4.

[0020] An application of the above-mentioned hole-rich molybdenum oxide nanosheets with near-infrared photocatalytic properties in the preparation of anti-tumor preparations targets tumor cell mitochondria and induces tumor cell death under near-infrared photocatalysis.

[0021] By adopting the above scheme, the method of the present invention has the following advantages:

[0022] 1. The present invention can accurately target cancer cell mitochondria and interfere with mitochondrial redox balance under near-infrared light irradiation, thereby destroying the mitochondrial structure and effectively inducing cancer cell death.

[0023] 2. The present invention adopts a hydrothermal method and performs triphenylphosphine modification to obtain mitochondrial-targeted, hole-rich, monodisperse molybdenum oxide nanosheets with near-infrared photocatalytic properties. The preparation method is simple and easy to operate.

[0024] 3. The methanol of the present invention can be used as a solvent in the reaction process. After the molybdenum oxide nanosheets are formed, it can also be used as a reducing agent to deprive the oxygen atoms in the molybdenum oxide nanosheets, thereby forming oxygen vacancies.

[0025] 4. The mitochondria-targeted monodisperse hole-rich molybdenum oxide nanosheets with near-infrared photocatalytic performance provided by the present invention have the advantages of being environmentally friendly, having strong biocompatibility, having no obvious toxicity to normal cells, having strong absorption of the entire spectrum, and having high photocatalytic activity. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] Figure 1 These are transmission electron micrographs of Example 1 before (a) and after (b) modification with triphenylphosphine.

[0027] Figure 2 This is the X-ray diffraction pattern of Example 1.

[0028] Figure 3 These are the electron paramagnetic resonance spectra of Examples 1 to 3.

[0029] Figure 4 It is the ultraviolet-visible-near-infrared absorption spectrum of Example 1.

[0030] Figure 5 This is a comparison chart of the cytotoxicity of Example 1 after co-incubation with human renal cortical proximal tubule epithelial cells for 24 hours.

[0031] Figure 6 The figures are the morphological changes of mitochondria in normal cells (a) and in Example 1 after incubation with mouse breast cancer cells and irradiation with near-infrared light (b).

[0032] Figure 7 This is a graph showing the cell survival rate after Example 1 was incubated with mouse breast cancer cells and irradiated with near-infrared light. DETAILED DESCRIPTION

[0033] The technical solutions in the embodiments of the present invention are described clearly and completely below. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of them. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0034] Embodiment 1:

[0035] (1) Take a clean single-mouth bottle, add 192 mg of metallic molybdenum powder and 20 mL of anhydrous methanol, slowly add 3 mL of 30% aqueous hydrogen peroxide solution under stirring in an ice-water bath, and stir for 30 minutes to obtain a clear yellow solution, i.e., a molybdenum precursor solution.

[0036] (2) The molybdenum precursor solution was then transferred to a 30 mL stainless steel autoclave containing a polytetrafluoroethylene liner and subjected to a hydrothermal reaction at 170°C for 12 hours; the solution was then naturally cooled to room temperature, washed with deionized water and ethanol, and the resulting product was vacuum dried at 60°C for 12 hours to obtain oxygen vacancy-rich molybdenum oxide nanosheets.

[0037] (3) 300 mg of molybdenum oxide nanosheets were dispersed in 15 mL of toluene using ultrasonic treatment and stirred vigorously to form a uniform suspension; next, 1 mL of 3-aminopropyltriethoxysilane was added to the suspension, and then refluxed at 110 ° C for 24 hours under an argon atmosphere; after the reaction was completed, the amino-functionalized precipitate was collected by centrifugation and washed three times with ethanol to remove the residual reactants, and the obtained precipitate was vacuum dried at 60 ° C. The product was obtained.

[0038] (4) Weigh 100 mg of the product obtained in step (3), disperse it in 100 mL of water by ultrasonic for 1 hour, adjust the pH of the system to 7.4 with dilute hydrochloric acid and sodium hydroxide solution, then add 0.5 g of active ester-polyethylene glycol-maleimide with a molecular weight of 2000 Da to the solution, and stir to react for 3 hours. Then, collect the precipitate by centrifugation at 12000 rpm for 15 minutes, and wash it with water 3 times.

[0039] (5) The precipitate obtained in step (4) was resuspended in 50 mL of water, the pH value was adjusted to neutral, and then 0.2 g of mercaptopropyltriphenylphosphonium was added, stirred for 2 hours, and the resulting precipitate was collected by centrifugation at 12000 rpm for 15 minutes, and washed with water 3 times to obtain triphenylphosphine-modified molybdenum oxide nanosheets rich in oxygen vacancies and having near-infrared photocatalytic properties.

[0040] Figure 1 It can be seen from the TEM image that the morphology of the hole-rich molybdenum oxide nanosheets modified with triphenylphosphine has not changed significantly compared with the unmodified product. Figure 2 The characteristic peaks in the XRD pattern match the standard card of molybdenum trioxide, and it can be seen from the figure that the obtained triphenylphosphine-modified hole-rich molybdenum oxide nanosheets have good crystallinity. Figure 4 The UV-Vis-NIR absorption spectrum shows that the hole-rich MoO2 nanosheets have full spectrum absorption properties.

[0041] Embodiment 2:

[0042] The difference from Example 1 is that the temperature of the hydrothermal reaction in step (2) is 150°C.

[0043] Embodiment 3:

[0044] The difference from Example 1 is that the temperature of the hydrothermal reaction in step (2) is 130°C.

[0045] Embodiment 4:

[0046] The difference from Example 1 is that the temperature of the hydrothermal reaction in step (2) is 200°C.

[0047] Example sample test:

[0048] Test the effect of hydrothermal reaction temperature on the content of oxygen vacancies: The electron paramagnetic resonance spectra of Examples 1 to 3 are as follows: Figure 3 As shown in the figure, the content of oxygen vacancies in the molybdenum oxide nanosheets synthesized in methanol increases with the increase of reaction temperature, indicating that the content of oxygen vacancies in the molybdenum oxide nanosheets can be controlled by the reaction temperature during the reaction process.

[0049] Cytotoxicity test: Human renal cortical proximal tubule epithelial cells were seeded in 96-well plates at 30,000 cells per well and cultured in a cell culture incubator for 12 hours to allow the cells to adhere to the wall. Then, the cells were cultured with 200, 100, 50, 25, and 12.5 μg / mL of triphenylphosphine-modified hole-rich molybdenum oxide nanosheets at 37°C for 24 hours, and then CCK was used to detect cell viability. The results are shown in Figure 2. Figure 5 As shown in the figure, it can be seen that no matter whether the triphenylphosphine-modified hole-rich molybdenum oxide nanosheets of the present invention are added at a high concentration or a low concentration, there is no obvious change in cell viability, indicating that the triphenylphosphine-modified hole-rich molybdenum oxide nanosheets have no obvious toxicity to normal cells.

[0050] Morphological changes of mitochondria in tumor cells: 4T1 cells were seeded in culture dishes and incubated for 24 h. Then, the cells were incubated with 50 μg / mL of mitochondria-targeted triphenylphosphine-modified hole-rich molybdenum oxide nanosheets at 37 °C for 6 h, and then illuminated with near-infrared light (1064 nm, 0.2 W / cm 2 Afterwards, the cells were washed with PBS, incubated with Hochest 3342 and Mito-tracker-Red to label the nucleus and mitochondria, and then imaged by laser confocal microscopy. Figure 6As shown, triphenylphosphine-modified hole-rich molybdenum oxide nanosheets can effectively destroy the mitochondrial structure of cancer cells under 1064nm wavelength light irradiation.

[0051] Tumor cell survival rate test: Mouse breast cancer cells (4T1 cells) were seeded into 96-well plates at 5000 cells / well and incubated in 5% CO 2 / 95% air in an incubator (Thermo) and cultured at 310K for 24 hours. The cells were then transferred to hypoxic culture conditions and cultured for another 24 hours to allow the cells to adapt to the hypoxic environment. 100, 50, 25, 12.5, and 6.25 μg / mL of triphenylphosphine-modified hole-rich molybdenum oxide nanosheets were prepared with cell culture medium and incubated with 4T1 cells for 4 hours. The culture medium was then replaced with a cell culture medium without phenol red, and the cells were placed under hypoxic conditions and irradiated with light of 1064 nm wavelength for 20 minutes. The cells were then placed in an incubator to recover for 36 hours, and the cell viability was determined by the CCK method. The results are shown in Figure 7 As shown, with the increase of the concentration of triphenylphosphine-modified hole-rich molybdenum oxide nanosheets, the survival rate of tumor cells decreases rapidly. Under the condition of 100 μg / mL concentration, the survival rate of tumor cells is even in single digits. This indicates that under the irradiation of light with a wavelength of 1064 nm, the triphenylphosphine-modified hole-rich molybdenum oxide nanosheets of the present invention can effectively induce cancer cell death.

[0052] For those skilled in the art, various other corresponding changes and deformations can be made according to the technical solutions and concepts described above, and all of these changes and deformations should fall within the protection scope of the claims of the present invention.

Claims

1. A hole-rich molybdenum oxide nanosheet with near-infrared photocatalytic performance, characterized in that: It is molybdenum oxide modified with triphenylphosphine; the diameter of the molybdenum oxide nanosheet is less than 100nm, the thickness is less than 10nm, and the light absorption wavelength range is 200~2000nm.

2. A method for preparing hole-rich molybdenum oxide nanosheets with near-infrared photocatalytic performance according to claim 1, characterized in that: The following steps are involved: Using metal molybdenum powder as a raw material, dispersing it in methanol, adding a hydrogen peroxide solution under ice bath conditions, and fully mixing to prepare a molybdenum precursor solution; The molybdenum precursor solution is subjected to hydrothermal reaction at 120-200°C for 12 hours; after being naturally cooled to room temperature, it is washed and dried with ethanol to obtain molybdenum oxide nanosheets; The molybdenum oxide nanosheets are modified with triphenylphosphine to obtain the product.

3. The method for preparing hole-rich molybdenum oxide nanosheets with near-infrared photocatalytic performance according to claim 2, characterized in that: The concentration of the molybdenum powder in methanol in step (1) is 5-20 mg / mL.

4. The method for preparing hole-rich molybdenum oxide nanosheets with near-infrared photocatalytic performance according to claim 2, characterized in that: The concentration of hydrogen peroxide added in step (1) in the system is 1% to 8%.

5. The method for preparing hole-rich molybdenum oxide nanosheets with near-infrared photocatalytic performance according to claim 2, characterized in that: The steps of triphenylphosphine modification include: The molybdenum oxide nanosheets are fully dispersed in toluene to form a uniform suspension of 15-25 mg / mL; 3-aminopropyltriethoxysilane is added to the suspension, and then refluxed at 100-120° C. for 20-28 hours under the protection of an argon atmosphere; after the reaction, the precipitate is collected by centrifugation and fully washed with ethanol to remove residual reactants, and the product is obtained after drying; The product was ultrasonically dispersed in water to obtain a dispersion of 0.8-1.2 mg / mL, and reacted with active ester-polyethylene glycol-maleimide under weak alkalinity for 2.5-3.5 h. The precipitate was collected by centrifugation and washed thoroughly with water. The obtained precipitate is dispersed in water, the pH of the system is adjusted to neutral, mercaptopropyltriphenylphosphine is added, mixed and reacted for 1.8 to 2.2 hours, centrifuged and washed with water three times, and the precipitate is collected to obtain the product.

6. The method for preparing hole-rich molybdenum oxide nanosheets with near-infrared photocatalytic performance according to claim 5, characterized in that: The mass ratio of the molybdenum oxide nanosheets to 3-aminopropyltriethoxysilane in step a is 1:3-4.

7. The method for preparing hole-rich molybdenum oxide nanosheets with near-infrared photocatalytic performance according to claim 5, characterized in that: The mass ratio of the product in step b to active ester-polyethylene glycol-maleimide is 1:4-6; the mass ratio of the product in step b to mercaptopropyltriphenylphosphine is 1:1.8-2.

2.

8. The method for preparing hole-rich molybdenum oxide nanosheets with near-infrared photocatalytic performance according to claim 5, characterized in that: The molecular weight of the active ester-polyethylene glycol-maleimide in step b is 1800-2200 Da.

9. The method for preparing hole-rich molybdenum oxide nanosheets with near-infrared photocatalytic performance according to claim 5, characterized in that: The weak alkalinity in step b is pH=7.0~8.

4.

10. Use of the hole-rich molybdenum oxide nanosheets with near-infrared photocatalytic properties according to claim 1 in the preparation of an anti-tumor preparation, characterized in that: Targeting tumor cell mitochondria and inducing tumor cell death under near-infrared photocatalysis.

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