Two-dimensional flower-shaped water-soluble photothermal conversion nanomaterial and synthesis method and near-infrared application thereof

Abstract

The application relates to a two-dimensional flower-shaped near-infrared responsive water-soluble photothermal conversion nanomaterial and a synthesis method and near-infrared application thereof. The two-dimensional copper sulfide nanosheet is prepared through a hydrothermal reaction, and gold nanoparticles are loaded on the edges of the two-dimensional nanosheet through gold-sulfur bonds, the content and molecular weight of the active agent on the surface of the nanosheet are controlled, the uniform loading of the gold nanoparticles is realized, and a composite material of a biomacromolecule and a biomimetic material modified inorganic nanomaterial is constructed. The nanomaterial prepared in the application has a unique two-dimensional flower-shaped morphology, has a wide spectrum absorption in the near-infrared region, and the maximum absorption peak extends to the NIR-IIa region, has the photothermal and photoacoustic performance in the near-infrared region, the material has effective brain tumor homing ability due to the T cell biomimetic membrane coating, the limitation of the nanomaterial in crossing the BBB is overcome, the tumor photothermal treatment effect is significantly enhanced, the biocompatibility is high and the material is non-toxic, no pollution is caused, the synthesis process is simple, the cost is low, and the material has a good treatment application prospect.

Description

Technical Field

[0001] This invention belongs to the field of nanomaterials and relates to a two-dimensional flower-shaped water-soluble photothermal conversion nanomaterial, its synthesis method, and its near-infrared applications. Background Technology

[0002] In recent years, photothermal nanomaterials used in photothermal therapy research have been mainly divided into two categories: inorganic photothermal materials and organic photothermal materials. Organic photothermal materials mainly include near-infrared responsive small molecules and semiconductor polymer nanoparticles, while inorganic photothermal materials mainly include multifunctional nanoparticles, such as nanocrystals, noble metal nanoparticles, black phosphorus, and metal oxysulfides. Compared with organic photothermal nanomaterials, inorganic photothermal materials have higher PCE and photothermal stability. However, there are still many problems with the current use of traditional inorganic photothermal nanomaterials for cancer treatment, such as low photothermal conversion efficiency and low penetration depth. Copper sulfide and gold are the most commonly used inorganic photothermal nanomaterials, with tunable local surface plasmon resonance (LSPR) characteristics, easy surface functionalization, and high biocompatibility. Constructing semiconductor heterojunctions to improve photothermal performance is one of the important methods for photothermal agent development in recent stages, and extending the ultraviolet absorption wavelength of photothermal agents in the near-infrared II region is also necessary for the diagnosis and treatment of the near-infrared II region. However, during the synthesis of copper sulfide and gold heterojunction materials, nanomaterial aggregation is prone to occur, significantly reducing the dispersibility of the heterojunction nanomaterials and limiting the improvement of their photothermal conversion efficiency. Furthermore, cetyltrimethylammonium bromide (CTAB), a commonly used raw material for preparing Au nanoparticles, greatly reduces the biocompatibility of the materials.

[0003] Nevertheless, photothermal nanomedicines still have certain limitations in biological clinical applications, such as excessively rapid in vivo metabolism, low biological stability, and poor targeting ability. Summary of the Invention

[0004] The technical problem to be solved by the present invention is to provide a near-infrared responsive two-dimensional water-soluble photothermal conversion nanomaterial that has a unique two-dimensional flower-like morphology, which overcomes the disadvantage of low dispersibility of nanomaterials and maximizes the loading of Au nanoparticles, thereby greatly improving the photothermal conversion efficiency of the material.

[0005] The technical solution adopted by the present invention to solve the above-mentioned problems is as follows:

[0006] A near-infrared responsive two-dimensional water-soluble photothermal conversion nanomaterial includes a cell membrane and a nanocomposite material encapsulated within the cell membrane. The nanocomposite material is a two-dimensional CuS nanosheet with Au nanoparticles loaded at its edges, exhibiting a flower-like shape. The two-dimensional CuS nanosheets have a hexagonal morphology, a sheet diameter of 20–60 nm, and a thickness of 10–20 nm. After loading Au nanoparticles at the edges, the particle size is 40–80 nm, wherein the Au nanoparticles are 10–30 nm in size.

[0007] The preparation method of the above-mentioned near-infrared responsive two-dimensional water-soluble photothermal conversion nanomaterials mainly includes the following steps:

[0008] (1) Soluble copper salt, sulfur source, surfactant, and anhydrous ethylenediamine are mixed in water to obtain precursor solution A;

[0009] (2) The precursor solution A was subjected to a hydrothermal reaction in a reactor to obtain hexagonal copper sulfide nanosheets (CuSNSs);

[0010] (3) Disperse hexagonal copper sulfide nanosheets in water to obtain a suspension; mix the suspension with N,N dimethylformamide (DMF) solvent evenly, then add triphenylphosphine gold chloride solution and mix, and finally add reducing agent hydrazine hydrate and continue mixing to obtain precursor solution B;

[0011] (4) Place the precursor solution B in an ice-water bath and sonicate for 4-12 hours to obtain CuS@Au heterojunction material, namely two-dimensional CuS nanosheets with edge-loaded Au nanoparticles (CuS@Au).

[0012] (5) A cell membrane was coated on the surface of a two-dimensional CuS nanosheet loaded with Au nanoparticles at the edge to obtain a near-infrared responsive two-dimensional water-soluble photothermal conversion nanomaterial.

[0013] According to the above scheme, the soluble metallic copper salt is one or more of copper nitrate, copper sulfate, copper chloride, etc., mixed in any proportion.

[0014] According to the above scheme, the surfactant is preferably polyvinylpyrrolidone with a molecular weight of 30,000 to 50,000.

[0015] According to the above scheme, the sulfur source is preferably thiourea or the like.

[0016] According to the above scheme, in the precursor solution A, the molar concentration range of both the soluble copper salt and the sulfur source is 0.1 to 1.0 mM, and the molar ratio of the sulfur source to the soluble copper salt is 1:1 to 1:5; the concentration of the surfactant in the precursor solution A is 1 to 10 mg / mL, and the volume percentage of anhydrous ethylenediamine in the precursor solution A is 0.2% to 0.5%.

[0017] According to the above scheme, the hydrothermal reaction is carried out in a high-pressure reactor at a temperature of 120℃ to 180℃ and a reaction time of 10 to 25 hours.

[0018] According to the above scheme, the ultraviolet absorption peak of the hexagonal copper sulfide nanosheets is in the range of 1000-1200 nm.

[0019] According to the above scheme, in step (2), after the reaction is complete, the mixture is cooled to room temperature, washed with water, and then concentrated in deionized water to form a suspension. The concentration of the suspension is calculated based on the dry weight of a certain volume of the suspension after drying.

[0020] According to the above scheme, in step (3), the volume ratio of the hexagonal copper sulfide nanosheet suspension to the N,N dimethylformamide (DMF) solvent is 1:50 to 1:150, wherein the concentration of the hexagonal copper sulfide nanosheet suspension is 5 to 15 mg / mL, the concentration of the triphenylphosphine gold chloride solution is 5 to 15 mg / mL (the solvent is DMF), the mass ratio of the hexagonal copper sulfide nanosheets to the triphenylphosphine gold chloride is 1:15 to 1:80, and the volume ratio of the reducing agent to the hexagonal copper sulfide nanosheet suspension is 1:20 to 1:150.

[0021] According to the above scheme, in step (3), the reducing agent is one or more of hydrazine hydrate, sodium citrate (solution), ascorbic acid (solution), etc., preferably, the reducing agent is hydrazine hydrate with a mass fraction of 85%.

[0022] According to the above scheme, in step (4), the ultrasonic conditions are a temperature of 0 to 5°C, a power of 20 to 150W, and an ultrasonic time of 4 to 12 hours.

[0023] According to the above scheme, in step (4), the ultraviolet absorption peak of CuS@Au heterojunction material is in the range of 1200 to 1400 nm.

[0024] According to the above scheme, step (5) specifically involves: ultrasonically mixing and dispersing the two-dimensional CuS nanosheet dispersion with edge-loaded Au nanoparticles with the cell membrane to uniformly coat the surface of the nanosheets; centrifuging the mixture after ultrasonication to remove excess cell membrane from the supernatant, and redispersing the resulting precipitate in deionized water or phosphate buffer solution to obtain the two-dimensional CuS nanosheet dispersion with edge-loaded Au nanoparticles coated with cell membrane (CuS@Au@CM dispersion), which is the dispersion of near-infrared responsive two-dimensional water-soluble photothermal conversion nanomaterial. The ultrasound time is 10–40 min; the mass ratio of the two-dimensional CuS nanosheets loaded with Au nanoparticles to the cell membrane is 4:1 to 1:1 (mass ratio based on dry weight); the cell membrane is extracted by lysis using a cell membrane extraction kit, and has the characteristics of targeting brain tumors and crossing the blood-brain barrier. It can be derived from one or more of mouse breast cancer cells (4T1 cell), mouse glioma cells (U87), lymphocytes, macrophages (J774A.1 cell), etc., preferably mouse T lymphocytes.

[0025] According to the above scheme, cell membranes are coated on the surface of two-dimensional CuS nanosheets with Au nanoparticles loaded at the edges, endowing the nanomaterial surface with complex cell membrane biological interface functions. The T lymphocyte membrane preferred in this invention imparts a lymphocyte homing effect to the CuS@Au nanomaterial, homing the material to specific tumor sites in the microenvironment, thereby achieving effective tumor enrichment and targeting.

[0026] This invention also provides a near-infrared responsive water-soluble photothermal conversion nanomaterial, which is a formulation formed by coating the near-infrared responsive water-soluble photothermal conversion nanomaterial of this invention with a cell membrane and dispersing it in a dispersant, wherein the mass ratio of CuS@Au@CM to the dispersant is (1-10)*10. -6 1. The dispersant is preferably phosphate buffered saline (PBS), with a pH generally between 7.2 and 7.6, and preferably pH ≈ 7.4.

[0027] The near-infrared responsive water-soluble photothermal conversion nanomaterials or their reagents described in this invention can be used as photothermal therapeutic agents for gliomas. In application, the laser can utilize a second near-infrared biological window (NIR-II; 1000–1700 nm) with a penetration depth and maximum permissible exposure superior to the NIR-I window, especially the NIR-IIa window (1300–1400 nm). This invention employs a laser of 800–1350 nm, specifically one or three of 808 nm, 1060 nm, and 1310 nm, with a power density of 0.5–1.5 W / cm². 2 The laser irradiation time is 5 to 10 minutes.

[0028] Compared with the prior art, the present invention has the following beneficial effects:

[0029] First, hexagonal, water-soluble copper sulfide (CuS) nanosheets were synthesized via a hydrothermal reaction. Then, gold nanoparticles (NPs) were loaded onto the edges of the two-dimensional nanosheets (NSs) via gold-sulfur bonds. Polyvinylpyrrolidone (PVP) was used as the surfactant on the nanosheet surface to achieve uniform loading of gold nanoparticles, forming a CuS@Au nanohybrid structure. This nanostructure possesses a unique two-dimensional flower-like morphology and achieves the maximum loading of Au nanoparticles while exhibiting good dispersibility, significantly improving the photothermal conversion efficiency of CuS@Au. The CuS@Au nanomaterial prepared in this invention exhibits broad-spectrum absorption in the near-infrared region, and its maximum ultraviolet absorption peak extends into the NIR-IIa region, thus enabling its application in NIR-IIa region diagnosis and treatment. The use of a CTAB-independent synthesis method in the preparation of the Au nanoparticles also improves the biocompatibility of the photothermal conversion material to some extent.

[0030] Secondly, in order to enhance the blood-brain barrier (BBB) ​​penetration ability and glioma targeting ability of the two-dimensional CuS nanosheet material with edge-loaded Au nanoparticles, a biomimetic membrane technology is used to coat the surface of the material with a cell membrane, endowing the surface of traditional nanomaterials with complex cell membrane biological interface functions. The immune cell T cell membrane selected in this invention enables the two-dimensional flower-like nanomaterial to have a certain tumor homing ability, homing the material to specific brain tumor sites in the microenvironment, and achieving effective brain tumor enrichment and targeting.

[0031] Finally, the two-dimensional water-soluble photothermal conversion nanomaterials of this invention have broad-spectrum absorption in the near-infrared region, and the maximum absorption wavelength is extended to the NIR-IIa region. They are suitable for the NIR-I window and the second near-infrared biological window (NIR-II; 1000-1700nm) with high penetration depth and high exposure, especially the NIR-IIa window (1300-1400nm), which has excellent effects in in vitro cell ablation and in vivo deep brain tissue anti-tumor ability. Attached Figure Description

[0032] Figure 1 The image shows a transmission electron microscope image of CuS NSs prepared in Example 1.

[0033] Figure 2 a is a transmission electron microscope image of CuS@Au prepared in Example 1; Figure 2 b is a transmission electron microscope image of CuS@Au prepared in Example 2;

[0034] Figure 3The image shows an atomic force microscope (AFM) image of CuS NSs prepared in Example 1.

[0035] Figure 4 The X-ray diffraction (XRD) patterns of CuS@Au, Au, and CuS NSs prepared in Example 1 are shown.

[0036] Figure 5 In the figure, a is the XPS result of CuS NSs prepared in Example 1, and b is the XPS result of CuS@Au;

[0037] Figure 6 In the diagram, a is the hydrated particle size distribution of CuS NSs in Example 1, and b is the hydrated particle size distribution of CuS@Au.

[0038] Figure 7 This is a transmission electron microscope image of CuS@Au coated on the cell membrane in Example 1 (i.e., CuS@Au@CM);

[0039] Figure 8 This is a study of the photothermal heating performance of the biomimetic nanomaterial CuS@Au@CM in Example 1; where Figure a shows the heating performance under 808nm laser conditions (1.1W / cm²). 2 Figure b shows the heating curve of a CuS@Au@CM solution with a concentration of 0.2 mg / mL under laser conditions (10 min, 808 nm). Figure c shows the cooling curve and photothermal conversion efficiency of the material under 1060 nm laser conditions (0.8 W / cm²). 2 The heating curves of CuS@Au@CM solutions with the same concentration (0.2 mg / ml) under laser conditions (10 min, 1060 nm) are shown in Figure d. Figure d shows the cooling curve and photothermal conversion efficiency of the material under this laser condition; Figure e shows the temperature rise curve under the laser condition (0.7 W / cm²) at 1310 nm. 2 Figure f shows the temperature change curves of CuS@Au@CM solutions with the same concentration (0.2 mg / mL) under the laser conditions at 10 min and 1310 nm. Figure g shows the cooling curve and photothermal conversion efficiency of the material under this laser condition. Figure h shows the photostability of CuS@Au@CM under the 1310 nm laser condition. Figure h compares the temperature change curves of CuS@Au@CM solutions with different powers under the 1310 nm laser.

[0040] Figure 9 This study evaluates the changes in penetration depth of the biomimetic nanomaterial CuS@Au@CM in in vitro tissues under different laser irradiation (808 nm, 1064 nm, and 1310 nm). The simulated tissue was pork tissue; Figure a shows the power density controlled at 1 W / cm². 2The solution heating curves under three laser conditions were obtained, and the material concentrations at 808 nm, 1060 nm, and 1310 nm were determined to be 0.3 mg / mL, 0.28 mg / mL, and 0.25 mg / mL, respectively. Figure b shows the solution heating curves under three different laser conditions (power 1 W / cm²). 2 Figure 1 shows the transmittance changes in pork tissue with different thicknesses (0, 2, 4, 6, 8, 10 mm); Figure 2 shows the temperature changes of the aqueous suspension of the material after penetrating tissue at different depths under different lasers.

[0041] Figure 10 The in vitro cytotoxicity and photothermal ablation ability tests of the biomimetic nanomaterial CuS@Au@CM are as follows: Figure a shows the cell viability after CuS@Au@CM was co-incubated with different cell types (U87—human glioblastoma cells, bEnd.3—mouse brain microvascular endothelial cells, 4T1—mouse breast cancer cells) for 4 hours; Figure b shows the comparison of cell viability of U87 cells after treatment with different laser conditions (808nm laser + CuS@Au@CM group, 1060nm laser + CuS@Au@CM group, 1310nm laser + CuS@Au@CM group); Figure c shows the images of U87 cells after treatment with different conditions, stained with propidium iodide (PI) and calcein (AM) for 30 min, under a confocal microscope (CSLM).

[0042] The above figures are all the corresponding figures involved in Embodiments 1 and 2. Detailed Implementation

[0043] The present invention will now be described in detail with reference to the accompanying drawings and specific embodiments. These embodiments are implemented based on the technical solution of the present invention, providing detailed implementation methods and specific operating procedures; however, the scope of protection of the present invention is not limited to the following embodiments.

[0044] Example 1

[0045] 1. Preparation of biomimetic nanomaterial CuS@Au@CM:

[0046] (1) Take a certain mass of copper chloride and thiourea powder and prepare aqueous solutions with concentrations of 0.25 mM and 0.5 mM respectively (each with a volume of 10 mL). Mix the two solutions evenly under ultrasonication, and add 10 mL of surfactant aqueous solution (100 mg of surfactant polyvinylpyrrolidone (molecular weight of 40000) is evenly dispersed in 10 mL of water to obtain surfactant aqueous solution). At this time, the total volume of the mixed solution is 30 mL. Then, place the mixed solution in a clean reaction vessel, add 100 μL of anhydrous ethylenediamine as a reducing agent below the liquid surface, tighten the reaction vessel and place it in a muffle furnace for reaction (160℃, 20 h). After the reaction is completed, remove the reaction vessel and cool it to room temperature (25℃). Wash the reaction product three times with deionized water (12500 rpm / min, 20 min) and disperse it in deionized water to prepare a copper sulfide suspension with a concentration of 10 mg / mL.

[0047] Take 50 μL of CuS NSs suspension in a round-bottom flask, add 5 mL of N,N-dimethylformamide (DMF), and stir with a magnetic stirrer for 5–10 min to mix evenly. Then add 10 mg / mL of triphenylphosphine gold chloride (DMF solvent, 3 mL volume) and continue stirring for 5–10 min to mix. Then add 1.5 μL of reducing agent hydrazine hydrate (mass fraction 85%) to the reaction solvent, and react in an ice-water bath with sonication for 12 h at 70 W. Wash and disperse to a concentration of 1 mg / mL suspension to obtain CuS@Au nanomaterials.

[0048] (2) Take a certain amount of T lymphocyte precipitate and lyse it using an extraction kit. Quantify the lysed cell membrane using a membrane protein kit (0.05 mg / mL). Then disperse it in a certain phosphate buffer solution (PBS, pH≈7.4) to a concentration of 0.01 mg / mL. Store it in a -80℃ freezer for long-term use.

[0049] Membrane coating was performed at a CuS@Au to cell membrane mass ratio of 3:1 (actual mass ratio). The cell membrane phosphate buffer solution was mixed with CuS@Au and coated under sonication for about 0.5 h. Then, the resulting mixture was centrifuged to remove excess cell membrane from the supernatant at a speed of 8000 rpm / min. The resulting precipitate was dispersed in an equal volume of PBS buffer solution to obtain CuS@Au@CM dispersion, which is a dispersion of near-infrared responsive two-dimensional water-soluble photothermal conversion nanomaterial.

[0050] 2. Characterization of biomimetic nanomaterial CuS@Au@CM:

[0051] according to Figure 1Transmission electron microscopy (TEM) revealed that copper sulfide morphology consisted of hexagonal sheets with a size of approximately 20–60 nm. Au nanoparticles were loaded onto the edges of the copper sulfide nanosheets. Figure 2 a) The morphology is flower-like, with a size of approximately 50–70 nm, of which Au nanoparticles are 10–30 nm in size. Figure 3 It can be seen that the thickness of the copper sulfide nanosheets is about 12.87 nm.

[0052] Depend on Figure 4 It can be seen that the CuS@Au prepared in the examples clearly shows the characteristic diffraction peaks of CuS (102), (103), (110) and Au (111), (200), (220), (311); according to Figure 5 It can be seen that this heterostructure is composed of Cu, S, and Au. Compared with pure CuS NSs, a clear positive electron shift can be observed, indicating the formation of Au-S bonds in the material. Figure 6 As shown in Figure a, the hydrated particle size of CuS NSs is measured, and the hydrated particle size of CuS@Au is measured. The hydrated particle size of CuS NSs is 48.91 nm, and the hydrated particle size of CuS@Au is 74.27 nm. This further demonstrates that the two-dimensional CuS nanosheets were successfully modified with Au nanoparticles to obtain CuS@Au nanomaterials.

[0053] After successful synthesis of CuS@Au nanomaterials, they were coated with cell membranes by ultrasound, negatively stained with uranium acetate, and analyzed by transmission electron microscopy. Figure 7 As shown, a cell membrane can be observed on the CuS@Au surface, indicating the successful preparation of the biomimetic nanomaterial CuS@Au@CM.

[0054] 3. Research on the photothermal effect of biomimetic nanomaterial CuS@Au@CM:

[0055] The photothermal effect of CuS@Au@CM was compared and evaluated under different laser conditions (808nm, 1060nm, 1310nm), as follows: Figure 8 As shown: a, c, and e are CuS@Au@CM aqueous solution at 808 nm (1.1 W / cm²). 2 ), 1060nm (0.8W / cm) 2 ), 1310nm (0.7W / cm) 2The heating curves under the three laser conditions (b, d, and f) after 15 min of illumination are shown. The cooling curves under these conditions and the calculated photothermal conversion efficiency of the two-dimensional nanomaterial CuS@Au@CM are also presented. The photothermal conversion efficiency was calculated based on the heat transfer time constant and the maximum steady-state temperature. The values ​​are 43.81% at 808 nm, 45.40% at 1060 nm, and a high 47.61% at 1310 nm. These results indicate that CuS@Au@CM can effectively convert NIR light into heat energy. Furthermore, to investigate the photostability of CuS@Au@CM, [f is missing from the original text]. Figure 8 As shown in g, the results showed that even after five irradiation cycles (1310 nm), no significant temperature change was observed in the CuS@Au@CM aqueous solution, indicating its excellent stability. Furthermore, it was found that the temperature rise of CuS@Au@CM increased significantly with increasing laser power, further demonstrating the excellent photothermal properties of CuS@Au@CM. Figure 8 h).

[0056] Because the NIR-II biological window has less tissue absorption and scattering, its tissue penetration depth is relatively greater than that of the NIR-I biological window. For example... Figure 9 As shown, to investigate the penetration ability of different laser conditions in biological tissues, pork tissue with thicknesses of 0, 2, 4, 6, 8, and 10 mm (2 cm long and 2 cm wide) was selected for in vitro photothermal simulation experiments in mice. According to... Figure 9 The temperatures of the three laser conditions (a) were used to determine the material concentrations under the 808nm NIR-I, 1060nm NIR-II, and 1310nm NIR-II laser conditions to be 0.3 mg / ml, 0.25 mg / ml, and 0.2 mg / ml, respectively. Based on this, the penetration ability of different lasers on pork tissue of different thicknesses was studied, and the calculated laser penetration rates were as follows: Figure 9 As shown in Figure b, the tissue penetration at 1310 nm is superior to that at 1060 nm and 808 nm. Temperature changes at different tissue depths measured under NIR-I and NIR-II laser irradiation indicate that, when penetrating tissue of the same thickness, the photothermal attenuation of the NIR-II laser is smaller than that of the NIR-I laser. Figure 9 c) The 1310nm laser exhibits the least attenuation. These results demonstrate the superior performance of the 1310nm NIR-II laser, highlighting the potential for deep tissue photothermal therapy using CuS@Au@CM within the NIR-I and NIR-II biological windows.

[0057] 4. Study on the in vitro biocompatibility and tumor cell killing effect of biomimetic nanomaterial CuS@Au@CM:

[0058] To investigate the in vitro biosafety of CuS@Au@CM and its potential for photothermal therapy of brain tumors, the in vitro toxicity of CuS@Au@CM to cells was assessed using the standard MTT assay. Figure 10 As shown in Figure a, different concentrations of CuS@Au@CM (0, 12, 25, 50, 100, and 200 μg mL) were used. -1 Incubation of CuS@Au@CM with breast cancer cells (4T1), glioma cells (U87), and mouse brain microvascular endothelial cells (bEnd.3) at 37°C and 5% CO2 for 4 h revealed that CuS@Au@CM had almost no effect on the survival rate of 4T1 and U87 cells, even at concentrations as high as 200 μg / mL. -1 No obvious toxic side effects were observed. Then, the therapeutic effect of CuS@Au@CM as an in vitro photothermal agent on photothermal ablation of brain tumor cells under laser irradiation was investigated. Figure 10 b) The results showed that the NIR-I and NIR-II lasers and CuS@Au@CM material had a better killing effect on U87 cells.

[0059] Furthermore, confocal microscopy (CLSM) imaging further confirmed the excellent photothermal therapeutic effect on U87 cells, such as... Figure 10 As shown in Figure c, U87 cells were seeded on cell culture dishes and incubated at 37°C in a 5% CO2 cell culture incubator for 24 hours. Then, CuS@Au@CM at certain concentrations (0, 12, 25, 50, 100, 200 μg / mL) was added and incubated for 4 hours. After that, different near-infrared lasers were used for irradiation. Live cells and dead cells were distinguished by co-staining with calcein (AM) and propidium iodide (PI), respectively. The results further demonstrated that CuS@Au@CM had a significant photothermal ablation effect on brain tumor cells under different laser conditions, and confirmed the possibility of the biomimetic nanomaterial CuS@Au@CM as a drug for the treatment of glioma.

[0060] Example 2

[0061] (1) The copper sulfide nanosheets synthesized in Example 1 were centrifuged at 12,500 rpm / min for 20 min under the same conditions, washed three times with deionized water, and then dispersed to prepare a copper sulfide suspension with a concentration of 10 mg / mL.

[0062] (2) Then take 50 μL of CuS NSs suspension, add 5 mL of DMF, stir with a magnetic stirrer for 5-10 min to mix evenly, continue to add 10 mg / mL of triphenylphosphine gold chloride solution (1 mL), mix, add 0.5 μL of reducing agent hydrazine hydrate (mass fraction of 85%), place in an ice water bath and sonicate for 12 h at a power of 70 W, wash and disperse to a concentration of 1 mg / mL suspension, thus obtaining a two-dimensional CuS nanosheet (CuS@Au nanomaterial) dispersion with edge-loaded Au nanoparticles.

[0063] Figure 2 b shows the transmission electron microscope morphology of the CuS@Au nanomaterials prepared in Example 2 of this invention.

[0064] (3) A certain amount of the CuS@Au nanomaterial dispersion prepared in Example 2 was subjected to ultrasonic membrane coating at a CuS@Au to cell membrane mass ratio of 3:1 (actual mass ratio) for about 0.5 h. Then, the resulting mixture was centrifuged to remove excess cell membrane from the supernatant at a centrifugation speed of 8000 rpm / min. The resulting precipitate was dispersed in an equal volume of phosphate buffered solution (PBS) to obtain CuS@Au@CM dispersion. The cell membrane used was obtained by lysing T cell precipitates using an extraction kit, quantifying the precipitate using a membrane protein kit (0.05 mg / mL), and finally dispersing it in a certain amount of PBS (concentration of 0.01 mg / mL).

[0065] The CuS@Au nanomaterials prepared in this embodiment exhibit excellent photothermal properties under near-infrared excitation and can be used as effective nanophotothermal conversion reagents for tumor ablation.

[0066] The above embodiments are provided to facilitate understanding and use by those skilled in the art. Others skilled in the art can make modifications to the above embodiments, applying the general principles of the invention to other embodiments. Therefore, the invention is not limited to the above embodiments, and modifications and improvements made without departing from the inventive concept of the invention are all within the scope of protection of the invention.

Claims

1. A near-infrared responsive two-dimensional water-soluble photothermal conversion nanomaterial, characterized in that, The two-dimensional water-soluble photothermal conversion nanomaterial is a two-dimensional CuS nanosheet with Au nanoparticles loaded at the edges, which is flower-shaped; a cell membrane is wrapped around the surface of the two-dimensional CuS nanosheet with Au nanoparticles loaded at the edges; wherein, the two-dimensional CuS nanosheet has a hexagonal morphology, a sheet diameter of 20-60 nm, a thickness of 10-20 nm, and after loading Au nanoparticles at the edges, the particle size is 40-80 nm, wherein the size of the Au nanoparticles is 10-30 nm. The preparation method of the two-dimensional water-soluble photothermal conversion nanomaterial includes the following steps: (1) A precursor solution A is obtained by mixing a soluble copper metal salt, thiourea, a surfactant, and anhydrous ethylenediamine in water. The surfactant is polyvinylpyrrolidone with a molecular weight of 30,000 to 50,000. (2) The precursor solution A was subjected to a hydrothermal reaction in a reactor to obtain hexagonal copper sulfide nanosheets; (3) Disperse hexagonal copper sulfide nanosheets in water to obtain a suspension; mix the suspension with N,N dimethylformamide solvent evenly, then add triphenylphosphine gold chloride solution and mix, and finally add reducing agent hydrazine hydrate and continue mixing to obtain precursor solution B; (4) Place the precursor solution B in an ice-water bath and sonicate for 4-12 h to obtain CuS@Au heterojunction material, namely two-dimensional CuS nanosheets with edge-loaded Au nanoparticles. (5) The surface of two-dimensional CuS nanosheets loaded with Au nanoparticles at the edge is coated with a cell membrane to obtain a two-dimensional water-soluble photothermal conversion nanomaterial with near-infrared response, and the maximum absorption wavelength is extended to 1300-1400 nm in the NIR-IIa region.

2. The method for preparing a near-infrared responsive two-dimensional water-soluble photothermal conversion nanomaterial according to claim 1, characterized in that, Includes the following steps: (1) A precursor solution A is obtained by mixing a soluble copper metal salt, thiourea, a surfactant, and anhydrous ethylenediamine in water. The surfactant is polyvinylpyrrolidone with a molecular weight of 30,000 to 50,000. (2) The precursor solution A was subjected to a hydrothermal reaction in a reactor to obtain hexagonal copper sulfide nanosheets; (3) Disperse hexagonal copper sulfide nanosheets in water to obtain a suspension; mix the suspension with N,N dimethylformamide solvent evenly, then add triphenylphosphine gold chloride solution and mix, and finally add reducing agent hydrazine hydrate and continue mixing to obtain precursor solution B; (4) Place the precursor solution B in an ice-water bath and sonicate for 4-12 h to obtain CuS@Au heterojunction material, namely two-dimensional CuS nanosheets with edge-loaded Au nanoparticles. (5) The surface of two-dimensional CuS nanosheets loaded with Au nanoparticles at the edge is coated with a cell membrane to obtain a two-dimensional water-soluble photothermal conversion nanomaterial with near-infrared response, and the maximum absorption wavelength is extended to 1300-1400 nm in the NIR-IIa region.

3. The method for preparing a near-infrared responsive two-dimensional water-soluble photothermal conversion nanomaterial according to claim 2, characterized in that, The soluble copper salt is one or a mixture of copper nitrate, copper sulfate, and copper chloride in any proportion; the reducing agent is one or more of hydrazine hydrate, sodium citrate solution, and ascorbic acid solution.

4. The method for preparing a near-infrared responsive two-dimensional water-soluble photothermal conversion nanomaterial according to claim 2, characterized in that, In the precursor solution A, the molar ratio of sulfur source to soluble copper salt is 1:1 to 1:5, and the molar concentration range of both soluble copper salt and sulfur source is 0.1 to 1.0 mM; the concentration of surfactant in precursor solution A is 1 to 10 mg / mL, and the volume percentage of anhydrous ethylenediamine in precursor solution A is 0.2% to 0.5%.

5. The method for preparing a near-infrared responsive two-dimensional water-soluble photothermal conversion nanomaterial according to claim 2, characterized in that, The hydrothermal reaction is carried out in a high-pressure reactor at a temperature of 120℃ to 180℃ for 10 to 25 hours; the ultraviolet absorption peak of the hexagonal copper sulfide nanosheets is in the range of 1000 to 1200 nm.

6. The method for preparing a near-infrared responsive two-dimensional water-soluble photothermal conversion nanomaterial according to claim 2, characterized in that, In step (3), the volume ratio of the hexagonal copper sulfide nanosheet suspension to N,N dimethylformamide solvent is 1:50 to 1:150; the concentration of the hexagonal copper sulfide nanosheet suspension is 5 to 15 mg / mL, the concentration of the triphenylphosphine gold chloride solution is 5 to 15 mg / mL, the mass ratio of the hexagonal copper sulfide nanosheets to triphenylphosphine gold chloride is 1:15 to 1:80; and the volume ratio of the reducing agent to the hexagonal copper sulfide nanosheet suspension is 1:20 to 1:

150.

7. The method for preparing a near-infrared responsive two-dimensional water-soluble photothermal conversion nanomaterial according to claim 2, characterized in that, Step (5) specifically involves: ultrasonically mixing and dispersing the two-dimensional CuS nanosheet dispersion with edge-loaded Au nanoparticles with the cell membrane to ensure uniform coating of the cell membrane on the nanosheet surface; centrifuging the ultrasonic mixture to remove excess cell membrane from the supernatant, and obtaining the precipitate as the near-infrared responsive two-dimensional water-soluble photothermal conversion nanomaterial, which is then redispersed in deionized water or phosphate buffer solution to obtain the cell membrane-coated two-dimensional CuS nanosheet dispersion with edge-loaded Au nanoparticles, i.e., the dispersion of the near-infrared responsive two-dimensional water-soluble photothermal conversion nanomaterial; wherein, the cell membrane can target brain tumors and cross the blood-brain barrier.

8. A near-infrared responsive water-soluble photothermal conversion nanoreagent, characterized in that, A formulation formed by dispersing the two-dimensional water-soluble photothermal conversion nanomaterials of claim 1 in a dispersant; wherein the mass ratio of the two-dimensional water-soluble photothermal conversion nanomaterials of claim 1 to the dispersant is (1-10) × 10. -6 :

1.

9. The application of the near-infrared responsive two-dimensional water-soluble photothermal conversion nanomaterial of claim 1 or the near-infrared responsive water-soluble photothermal conversion nanoreagent of claim 8 in the preparation of photothermal therapy drugs for glioma.

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