Near-infrared light response metalloid molybdenum-based nanoscale enzyme, preparation method and application
Near-infrared II photoresponsive molybdenum-based nanozymes were prepared by mesoporous silica and metal-acid treatment, which solved the problems of selective accumulation of nanomaterials at tumor sites and insufficient photocatalytic performance, achieving efficient photothermal conversion and photocatalytic effects, and enhancing anti-cancer efficacy.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Patents(China)
- Current Assignee / Owner
- NORTHEAST FORESTRY UNIV
- Filing Date
- 2023-06-09
- Publication Date
- 2026-05-12
AI Technical Summary
Existing nanomaterials lack the selective accumulation at lesion sites in near-infrared II phototherapy, affecting normal tissues. Furthermore, the photocatalytic performance of photothermal agents or photosensitizers is insufficient, making it difficult to achieve efficient photothermal conversion and photocatalysis.
Using mesoporous silica as a template, near-infrared II photoresponsive molybdenum-based nanozymes were prepared by doping molybdenum oxide into nanomaterials through a metal-acid treatment strategy and combined with hyaluronic acid modification, thus endowing them with bioresponsive degradation and excellent light absorption and photothermal conversion properties.
It achieves selective retention and efficient photothermal conversion of nanozymes at tumor sites, generates reactive oxygen species, enhances anti-cancer efficacy, and possesses excellent photocatalytic performance and biocompatibility.
Smart Images
Figure CN117180425B_ABST
Abstract
Description
Technical Field
[0001] This invention relates to the field of nanozyme preparation technology, and in particular to a near-infrared II photoresponsive molybdenum-based nanozyme, its preparation method, and its application. Background Technology
[0002] With the rapid development of therapeutic nanomedicine, nanomaterials can be designed to respond to specific stimuli, including endogenous stimuli such as low pH and hypoxia, as well as external physical stimuli such as temperature, light, magnetic fields, and ultrasound, to achieve tumor-specific therapy. Molybdenum (Mo), as a non-toxic and low-cost transition metal, is used to develop photoresponsive nanomaterials with diverse physicochemical properties to achieve multiple functions. Molybdenum-based nanomedicines not only provide effective catalytic sites or multivalent elements but also exhibit excellent photoresponsive therapeutic functions under laser irradiation. Near-infrared (NIR) laser-induced photothermal therapy and photodynamic therapy are two major phototherapy methods. However, most nanomaterials face the challenge of not selectively accumulating at lesion sites and interfering with normal tissue, thus affecting treatment. Furthermore, even those that can effectively absorb NIR-II light rarely achieve high photothermal conversion efficiency or excellent photocatalytic performance to generate reactive oxygen species through NIR-II.
[0003] Therefore, the research and development of a near-infrared II photoresponsive, biodegradable, molybdenum-based nanozyme is of great significance to the biomedical field, and no such nanozyme scheme or route has been reported before. Summary of the Invention
[0004] To address the aforementioned technical problems, this invention offers a possible solution: using mesoporous silica (MSNs) as a template, a metal-acid treatment strategy is employed to hydrogenate molybdenum oxide nanomaterials loaded within the MSNs mesopores. This hydrogen-doped approach enables bioresponsive degradation, and the resulting metalloid electronic structure endows the nanomaterials with highly efficient NIR-II light absorption, photothermal conversion, and photocatalytic properties similar to metals. Furthermore, appropriate surface modification of anticancer nanozymes with hyaluronic acid (HA) can enhance their permeability and retention, thereby improving their selective retention at tumor sites. Therefore, this invention provides a near-infrared II photoresponsive molybdenum-based metalloid nanozyme, its preparation method, and its applications, thus resolving the aforementioned problems in the prior art.
[0005] To achieve the above objectives, the technical solution adopted by the present invention is as follows:
[0006] In a first aspect, the present invention provides a method for preparing near-infrared II photoresponsive molybdenum-based nanozymes, comprising the following steps:
[0007] S1, Preparation of mesoporous silica-supported molybdenum oxide: Mesoporous silica MSNs are dispersed in an organic solvent, and a mixed solution of urea, ammonium chloride and molybdenum acetylacetone are added respectively. After stirring, the mixture is dried at 40-60℃ to obtain a solid. The solid is then calcined to obtain mesoporous silica-supported molybdenum oxide, denoted as MMSNs.
[0008] S2, Preparation of mesoporous silica-supported metal-like molybdenum hydride oxide: MMSNs are dispersed in an acidic solution, and zinc powder is added to react and a black product is obtained. After separation, washing and drying of the black product, mesoporous silica-supported metal-like molybdenum hydride oxide is obtained, denoted as HMMSNs.
[0009] S3, modified with hyaluronic acid (HA): HMMSNs and HA were fully dissolved in an organic solvent, mixed and stirred for 10–14 h, and then separated, washed and dried to obtain molybdenum-based nanozymes, denoted as HMMSNs@HA.
[0010] Preferably, step S1 specifically includes: dispersing 25-40 mg MSNs in anhydrous ethanol, then adding a mixed solution of urea and ammonium chloride dissolved in water and anhydrous ethanol to the above solution, then adding 0.3-0.4 g of molybdenum acetylacetonate dissolved in 20-30 mL of anhydrous ethanol, stirring the resulting mixed solution thoroughly, and then drying the solvent overnight in an oven at 40-60°C; grinding the dried solid and then calcining it in a muffle furnace under gradient heating to a final temperature of 400°C for 4-6 h to obtain MMSNs.
[0011] Preferably, the mixed solution of urea and ammonium chloride dissolved in water and anhydrous ethanol is prepared by dissolving 2-3g of urea and 0.5-0.6g of ammonium chloride in 5-10mL of water and 10-20mL of anhydrous ethanol.
[0012] Preferably, step S2 specifically includes: uniformly dispersing 0.1-0.2g of the prepared MMSNs powder in 20-30mL of hydrochloric acid solution with a concentration of 3-5M, then rapidly adding 0.1-0.2g of metallic zinc powder at 500-700rpm to react and obtain a black product, centrifuging to separate the product, washing it 3-5 times with deionized water and anhydrous ethanol, and drying it in a vacuum oven at 40-60℃ for 10-14h.
[0013] Preferably, step S3 specifically includes: first, dissolving the synthesized HMMSNs in anhydrous ethanol, then dissolving HA in anhydrous ethanol. After both are fully dissolved, they are mixed and placed under magnetic stirring at 40-60°C for 10-14 hours. After the reaction, the mixture is centrifuged, washed with deionized water and anhydrous ethanol, and the collected product is placed in an oven and dried at 40-60°C for 10-14 hours to obtain HMMSNs@HA.
[0014] The mass ratio of HMMSNs to HA is 1:1 to 1:2.
[0015] Preferably, before step S1, the preparation of mesoporous silica is further included, specifically comprising the following steps:
[0016] First, 0.8–1.5 g of cetyltrimethyl-p-toluenesulfonate (CTA·Tos), 0.1–0.15 g of triethanolamine, and 8–15 mg of 1-butyl-3-methyl-imidazolium trifluoromethanesulfonate were mixed in deionized water. The resulting mixture was then stirred at 80–100 °C for 1–2 h. 7–8 mL of tetraethyl orthosilicate was added, and the reaction was continued at 80–100 °C for 2–3 h. The resulting product was then centrifuged and washed. Finally, template removal was performed to remove the template CTA·Tos. The centrifuged and washed product was dispersed in anhydrous ethanol, stirred, and soaked for 20–24 h. It was then centrifuged for 5–10 min and washed twice with anhydrous ethanol. Finally, the product was transferred to an oven at 40–60 °C and dried. The resulting white powder is MSNs.
[0017] In a second aspect, the present invention provides a near-infrared II photoresponsive molybdenum-based nanozyme prepared by the preparation method described in the first aspect.
[0018] Thirdly, the present invention also provides the application of near-infrared II photoresponsive molybdenum-based nanozymes in drug carriers.
[0019] The beneficial effects of this invention are:
[0020] This invention provides a near-infrared II photoresponsive molybdenum-based nanozyme, its preparation method, and its applications. Using mesoporous silica (MSNs) as a template, Mo-doped MSNs nanospheres are synthesized via calcination and a metal-acid treatment strategy to obtain HMMSNs@HA nanospheres. MSNs effectively control the morphology of the small-sized material due to their unique porosity. HA modification significantly enhances its tumor targeting and biocompatibility. The hydrogenation process involves infiltrating electrons from Mo and protons from the acid into the molybdenum oxide as doped hydrogen, thereby endowing the nanozyme with a bioresponsive degradation ability that allows it to function stably in the tumor microenvironment while rapidly degrading under physiological conditions. Furthermore, the hydrogenation process endows the nanozyme with an unusual metalloid electronic structure, giving the molybdenum-based nanozyme excellent near-infrared II (1064 nm) light absorption, photothermal conversion, and photoresponsive oxidase-like activity, specifically generating superoxide anion free radicals to scavenge cancer cells under 1064 nm laser irradiation.
[0021] Furthermore, the molybdenum ions at a certain concentration in this HMMSNs@HA nanozyme can catalyze a Fenton-like reaction to generate hydroxyl radicals through its peroxidase-like activity. Simultaneously, its photothermal effect can promote the enzyme-catalyzed reaction, thereby generating more reactive oxygen species that kill cancer cells, further enhancing its anti-cancer efficacy. The resulting HMMSNs@HA nanozyme also possesses a mesoporous structure and a considerable size and morphology, enabling it to not only load drugs but also accumulate at the tumor site through high permeability and retention effects, fully exerting its anti-cancer effect. These numerous advantages make it an ideal nanozyme for anti-cancer treatment. Attached Figure Description
[0022] Figure 1 These are scanning electron microscope images of dendritic mesoporous silica (MSNs).
[0023] Figure 2 These are transmission electron microscope images of dendritic mesoporous silica (MSNs).
[0024] Figure 3 These are transmission electron microscope images of molybdenum oxide MMSNs loaded in mesoporous silica prepared in Example 1;
[0025] Figure 4 These are transmission electron microscope images of HMMSNs prepared by metal-acid treatment;
[0026] Figure 5 These are the nitrogen adsorption and desorption curves of HMMSNs prepared by metal-acid treatment;
[0027] Figure 6 This is the pore size distribution curve of HMMSNs prepared by metal-acid treatment. Detailed Implementation
[0028] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to the accompanying drawings. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the invention.
[0029] Example 1
[0030] This embodiment provides a near-infrared II photoresponsive molybdenum-based metalloid nanozyme, the preparation method of which includes the following steps:
[0031] (1) Synthesis of mesoporous silica (MSNs): First, 0.95 g of cetyltrimethylammonium p-toluenesulfonate (CTA·Tos), 0.105 g of triethanolamine, and 10 mg of 1-butyl-3-methyl-imidazolium trifluoromethanesulfonate were mixed in 50 mL of deionized water, and the resulting mixture was stirred at 80 °C for 1 h. Then, 7.8 mL of tetraethyl orthosilicate was rapidly added to the mixture, and the reaction was continued at 80 °C for 2 h. Next, the product was centrifuged at 11000 r / min for 5 min and washed twice with anhydrous ethanol and deionized water, respectively. Then, template removal was performed to remove the template CTA·Tos. The centrifuged and washed product was dispersed in 120 mL of anhydrous ethanol, stirred and soaked for 24 h, and then centrifuged at 11000 r / min for 5 min and washed twice with anhydrous ethanol. Finally, the centrifuged product was transferred to a 60 °C oven and dried overnight. The resulting white powder was MSNs. Its structure was characterized, and its scanning electron microscope image is shown below. Figure 1 As shown, the particle size is approximately 100 nm; the corresponding transmission electron microscope image is shown below. Figure 2 As shown in the image, it has a distinct dendritic mesoporous structure.
[0032] (2) Preparation of molybdenum oxide-loaded mesoporous silica (MMSNs): First, 30 mg of synthesized mesoporous silica was ultrasonically dispersed in 10 mL of anhydrous ethanol to obtain solution A. Then, 2.7 g of urea and 0.54 g of ammonium chloride were fully dissolved in 5 mL of deionized water and 10 mL of anhydrous ethanol to obtain solution B. Next, 0.33 g of molybdenum acetylacetonate was ultrasonically dispersed in 20 mL of anhydrous ethanol to obtain solution C. Then, solution B was stirred and added to solution A, and the mixture was stirred at room temperature for 3 h. Then, solution C was added to the mixed solution and stirred thoroughly for 6 h. The resulting mixture was then dried overnight in an oven at 60 °C. The obtained solid was ground into powder and calcined in a muffle furnace at 100 °C intervals for 2 h each time, with a final temperature of 400 °C for 6 h, to obtain molybdenum oxide-loaded MMSNs in mesoporous silica. The structure was characterized, and transmission electron microscopy images were obtained as follows. Figure 3 As shown, the particle size is about 130 nm, and molybdenum oxide was successfully loaded.
[0033] (3) Preparation of metal-like molybdenum hydride nanoparticles (HMMSNs) supported in mesoporous silica: HMMSNs with a metal-acid treatment method were synthesized. Typically, 0.1 g of the prepared MMSNs nanomaterials were uniformly dispersed in 20 mL of 4M hydrochloric acid solution by gentle ultrasonication. Then, 0.15 g of zinc powder was rapidly added under constant stirring (600 rpm), and the reaction was continued for 3 min. The resulting product was then centrifuged at 11000 r / min for 5 min and washed three times with deionized water and anhydrous ethanol. Finally, the black centrifuged product was dried overnight in a vacuum oven at 60 °C to obtain the metal-like molybdenum hydride nanoparticles (HMMSNs) supported in mesoporous silica. Transmission electron microscopy images were obtained for characterization, as shown below. Figure 4 As shown in the figure, it can be seen that it has a distinct mesoporous structure and a particle size of approximately 130 nm.
[0034] In addition, to test its pore size, a nitrogen adsorption experiment was conducted, and the nitrogen adsorption and desorption curves of HMMSNs were obtained as follows: Figure 5 As shown, the curve belongs to type IV isotherm and has a typical mesoporous structure; the corresponding pore size distribution curve is as follows. Figure 6 As shown in the two figures, the specific surface area and average pore size of the HMMSNs nanozyme are 55.1 μm. 2 / g and 15.7nm.
[0035] (4) Hyaluronic acid (HA) modification: First, 40 mg of the synthesized HMMSNs was dissolved in anhydrous ethanol, and then 60 mg of HA was dissolved in anhydrous ethanol. After both were fully dissolved, they were mixed and placed in a 60°C magnetic stirring container overnight. The resulting product was then centrifuged at 10,000 r / min and washed several times with deionized water and anhydrous ethanol. Finally, the final product was dried in a 60°C oven overnight to obtain HMMSNs@HA.
[0036] Example 2
[0037] This embodiment provides a near-infrared II photoresponsive molybdenum-based metalloid nanozyme, the preparation method of which includes the following steps:
[0038] (1) Synthesis of mesoporous silica (MSNs): First, 0.8 g of cetyltrimethylammonium p-toluenesulfonate (CTA·Tos), 0.1 g of triethanolamine, and 8 mg of 1-butyl-3-methyl-imidazolium trifluoromethanesulfonate were mixed in 50 mL of deionized water, and the resulting mixture was stirred at 100 °C for 1 h. Then, 7 mL of tetraethyl orthosilicate was quickly added to the mixture, and the reaction was continued at 80 °C for 2.5 h with stirring. Next, the product was centrifuged at 11000 r / min for 5 min and washed twice with anhydrous ethanol and deionized water, respectively. Then, the template CTA·Tos was removed. The centrifuged and washed product was dispersed in 100 mL of anhydrous ethanol, stirred and soaked for 20 h, and then centrifuged at 11000 r / min for 5 min and washed twice with anhydrous ethanol. Finally, the centrifuged product was transferred to a 40 °C oven and dried overnight. The resulting white powder was MSNs.
[0039] (2) Preparation of molybdenum oxide supported on mesoporous silica (MMSNs): First, 25 mg of synthesized mesoporous silica was ultrasonically dispersed in 10 mL of anhydrous ethanol to obtain solution A. Then, 2 g of urea and 0.5 g of ammonium chloride were fully dissolved in 7 mL of deionized water and 15 mL of anhydrous ethanol to obtain solution B. Next, 0.3 g of molybdenum acetylacetonate was ultrasonically dispersed in 25 mL of anhydrous ethanol to obtain solution C. Then, solution B was stirred and added to solution A, and the mixture was stirred at room temperature for 3 h. Then, solution C was added to the mixed solution and stirred thoroughly for 6 h. The resulting mixture was then dried overnight in an oven at 50 °C. The obtained solid was ground into powder and calcined in a muffle furnace at 100 °C intervals for 2 h each time, with a final temperature of 400 °C for 5 h, to obtain MMSNs.
[0040] (3) Preparation of metal-like molybdenum hydride nanoparticles (HMMSNs) supported on mesoporous silica: HMMSNs with metal-like electronic structures were synthesized by a metal-acid treatment method. Under normal conditions, 0.1 g of the prepared MMSNs nanomaterials were uniformly dispersed in 25 mL of 3M hydrochloric acid solution by slight ultrasonication. Then, 0.1 g of zinc powder was rapidly added under constant stirring (600 rpm) and the reaction was continued for 5 min. The product was then centrifuged at 11000 r / min for 5 min and washed three times with deionized water and anhydrous ethanol. Finally, the black centrifuged product was dried overnight in a vacuum oven at 40 °C to obtain HMMSNs.
[0041] (4) Hyaluronic acid (HA) modification: First, 40 mg of the synthesized HMMSNs was dissolved in anhydrous ethanol, and then 40 mg of HA was dissolved in anhydrous ethanol. After both were fully dissolved, they were mixed and placed in a 40°C magnetic stirring container overnight. The resulting product was then centrifuged at 10,000 r / min and washed several times with deionized water and anhydrous ethanol. Finally, the final product was dried in a 40°C oven overnight to obtain HMMSNs@HA.
[0042] Example 3
[0043] This embodiment provides a near-infrared II photoresponsive molybdenum-based metalloid nanozyme, the preparation method of which includes the following steps:
[0044] (1) Synthesis of mesoporous silica (MSNs): First, 1.5g of cetyltrimethylammonium p-toluenesulfonate (CTA·Tos), 0.15g of triethanolamine and 15mg of 1-butyl-3-methyl-imidazolium trifluoromethanesulfonate were mixed in a certain amount of deionized water, and then the resulting mixed solution was stirred at 100℃ for 1h.
[0045] 8 mL of tetraethyl orthosilicate was quickly added to the mixture, and the mixture was stirred at 100 °C for 2 h. The resulting product was then centrifuged (10000-11000 r / min) and washed twice with anhydrous ethanol and deionized water.
[0046] Finally, the template CTA·Tos was removed by template removal treatment. The product after centrifugation and washing was dispersed in 150 mL of anhydrous ethanol, stirred and soaked for 20 h, then centrifuged at 10000-11000 r / min for 10 min and washed twice with anhydrous ethanol. Finally, the product was transferred to a 60℃ oven to dry. The white powder obtained is MSNs.
[0047] (2) Preparation of molybdenum oxide supported on mesoporous silica (MMSNs): First, 40 mg of synthesized MSNs were ultrasonically dispersed in 20 mL of anhydrous ethanol. Then, a mixed solution of 3 g of urea and 0.6 g of ammonium chloride dissolved in 10 mL of water and 20 mL of anhydrous ethanol was added to the above solution. Next, 0.4 g of molybdenum acetylacetonate dissolved in 30 mL of anhydrous ethanol was added. The resulting mixed solution was stirred thoroughly, and then the solvent was dried overnight in an oven at 40–60 °C. The obtained powder was ground and then calcined in a muffle furnace under gradient heating to a final temperature of 400 °C for 4 h to obtain MMSNs.
[0048] (3) Preparation of metal-like molybdenum hydride spores (HMMSNs) supported on mesoporous silica: HMMSNs with a metal-acid treatment method were synthesized. Typically, 0.2 g of the prepared MMSNs powder was uniformly dispersed in 30 mL of 5 M hydrochloric acid solution by gentle ultrasonication, and then 0.2 g of zinc powder was rapidly added under constant stirring (500–700 rpm). The resulting black product was then centrifuged at 10,000–11,000 rpm for 5–10 min, washed three times with deionized water and anhydrous ethanol, and dried in a vacuum oven at 40–60 °C for 10–14 h to obtain the HMMSNs.
[0049] (4) Hyaluronic acid (HA) modification: First, dissolve 40 mg of the synthesized HMMSNs in anhydrous ethanol, and then dissolve 80 mg of HA in anhydrous ethanol. After both are fully dissolved, mix them and place them under magnetic stirring at 50°C for 10–14 h. Then centrifuge at 10,000–11,000 r / min for 5–10 min, wash with deionized water and anhydrous ethanol, collect the product, and place it in an oven to dry at 40–60°C for 14 h to obtain HMMSNs@HA.
[0050] By adopting the above-disclosed technical solution of this invention, the following beneficial effects are obtained:
[0051] This invention discloses a method for preparing a mesoporous structure, a metal-like hydrogenated molybdenum oxide nanozyme with high tumor targeting and biocompatibility, near-infrared II photoresponse, and biodegradability, which can be loaded onto mesoporous silica nanospheres. This invention has four characteristics: First, the preparation method for synthesizing this material includes four steps: First, using tetraethyl orthosilicate as a silicon source, mesoporous silica nanospheres with good dispersibility and uniform particle size are synthesized; second, MMSNs nanospheres are synthesized by in-situ doping of metallic Mo into the mesopores of MSNs through calcination; third, molybdenum oxide loaded in mesoporous silica is hydrogenated through a metal-acid treatment strategy to endow it with an excellent metal-like electronic structure; and fourth, the HMMSNs nanozyme is synthesized through HA modification. The four-step synthesis process is simple, easy, and safe, producing spherical nanozymes with good dispersibility and uniform particle size distribution. Secondly, the hydrogenation process infuses electrons from metallic Mo and protons from the acid into the metallic molybdenum oxide as doped hydrogen, endowing the molybdenum-based nanozyme with biodegradability—able to function stably in the tumor microenvironment while rapidly degrading under normal physiological conditions. Thirdly, the hydrogenation process reduces the band gap of the nanozyme, while generating dense and continuous electrons near the Fermi level, resulting in an excellent metalloid electronic structure. This endows the molybdenum-based nanozyme with efficient NIR-II light absorption. Furthermore, its high electron concentration surface plasmon resonance effect further enhances the photothermal conversion efficiency of the nanozyme and its ability to generate superoxide anion radicals (oxidase-like) under 1064nm laser irradiation. Fourthly, the synthesized HMMSNs can also act as peroxidase-like catalyze Fenton-like reactions to generate hydroxyl radicals. Simultaneously, the catalytic activity of this enzyme is further enhanced by the photothermal effect, thus exerting a more efficient anti-cancer effect. Therefore, it can serve as an excellent molybdenum-based nanozyme for cancer treatment.
[0052] The above description is only a preferred embodiment of the present invention. It should be noted that for those skilled in the art, several improvements and modifications can be made without departing from the principle of the present invention, and these improvements and modifications should also be considered within the scope of protection of the present invention.
Claims
1. A method for preparing a near-infrared II photoresponsive molybdenum-based nanozyme, characterized in that, Includes the following steps: S1, Preparation of mesoporous silica-supported molybdenum oxide: Mesoporous silica MSNs are dispersed in an organic solvent, and a mixed solution of urea, ammonium chloride and molybdenum acetylacetone are added respectively. After stirring, the mixture is dried at 40-60°C to obtain a solid. The solid is then calcined to obtain mesoporous silica-supported molybdenum oxide, denoted as MMSNs. S2, Preparation of mesoporous silica-supported metal-like molybdenum hydride oxide: MMSNs are dispersed in an acidic solution, and zinc powder is added to react and a black product is obtained. After separation, washing and drying of the black product, mesoporous silica-supported metal-like molybdenum hydride oxide is obtained, denoted as HMMSNs. S3, modified with hyaluronic acid (HA): HMMSNs and hyaluronic acid (HA) were dissolved separately in organic solvents to obtain organic solutions of HMMSNs and HA. After mixing and stirring for 10–14 h, the solutions were separated, washed, and dried to obtain molybdenum-based nanozymes, denoted as HMMSNs@HA. Before step S1, the process also includes synthesizing mesoporous silica nanospheres with good dispersibility and uniform particle size using tetraethyl orthosilicate as the silicon source; Step S1 specifically includes: 25–40 mg of MSNs were dispersed in anhydrous ethanol. A mixed solution of urea and ammonium chloride dissolved in water and anhydrous ethanol was then added to the above solution. Next, 0.3–0.4 g of molybdenum acetylacetonate dissolved in 20–30 mL of anhydrous ethanol was added. The resulting mixture was stirred thoroughly and then dried overnight in an oven at 40–60 °C. The dried solid was ground and then calcined in a muffle furnace under gradient heating to a final temperature of 400 °C for 4–6 h to obtain MMSNs. Step S2 specifically includes: 0.1–0.2 g of the prepared MMSNs powder was uniformly dispersed in 20–30 mL of 3–5 M hydrochloric acid solution. Then, 0.1–0.2 g of metallic zinc powder was rapidly added at 500–700 rpm to react and obtain a black product. The product was separated by centrifugation, washed 3–5 times with deionized water and anhydrous ethanol, and dried in a vacuum oven at 40–60 °C for 10–14 h. Step S3 specifically includes: First, the synthesized HMMSNs were dissolved in anhydrous ethanol, and then HA was dissolved in anhydrous ethanol. After both were fully dissolved, they were mixed and placed under magnetic stirring at 40-60°C for 10-14 hours. After the reaction, the mixture was centrifuged and washed with deionized water and anhydrous ethanol. The collected product was then placed in an oven and dried at 40-60°C for 10-14 hours to obtain HMMSNs@HA. The mass ratio of HMMSNs to HA is 1:1 to 1:
2.
2. The method for preparing near-infrared II photoresponsive molybdenum-based nanozymes according to claim 1, characterized in that, The specific method for preparing a mixed solution of urea and ammonium chloride dissolved in water and anhydrous ethanol is to dissolve 2-3g of urea and 0.5-0.6g of ammonium chloride in 5-10mL of water and 10-20mL of anhydrous ethanol.
3. The method for preparing near-infrared II photoresponsive molybdenum-based nanozymes according to claim 1, characterized in that, Before step S1, the preparation of mesoporous silica is also included, specifically comprising the following steps: First, 0.8–1.5 g of cetyltrimethyl-p-toluenesulfonate (CTA·Tos), 0.1–0.15 g of triethanolamine, and 8–15 mg of 1-butyl-3-methyl-imidazolium trifluoromethanesulfonate were mixed in deionized water. The resulting mixture was then stirred at 80–100 °C for 1–2 h. 7–8 mL of tetraethyl orthosilicate was added, and the reaction was continued at 80–100 °C for 2–3 h. The resulting product was then centrifuged and washed. Finally, template removal was performed to remove the template CTA·Tos. The centrifuged and washed product was dispersed in anhydrous ethanol, stirred, and soaked for 20–24 h. It was then centrifuged for 5–10 min and washed twice with anhydrous ethanol. Finally, the product was transferred to an oven at 40–60 °C and dried. The resulting white powder is MSNs.
4. Near-infrared II photoresponsive molybdenum-based nanozymes prepared by any of the preparation methods described in claims 1-3.
5. The application of the near-infrared II photoresponsive molybdenum-based nanozyme of claim 4 in the preparation of drug carriers.