A multimetallic synergistic network nanoplatform and a preparation method and application thereof

Abstract

This invention relates to a multi-metal synergistic network nanoplatform, characterized in that the multi-metal synergistic network nanoplatform comprises particles and a framework, the particles comprising copper-containing particles and iron, the framework comprising manganese dioxide, and the particles being doped into the framework. The preparation method of the multi-metal synergistic network nanoplatform includes the following steps: preparation of the framework; preparation of the iron-doped framework; and preparation of the nanoplatform. This invention also provides a drug for treating tumors, comprising a drug and the multi-metal synergistic network nanoplatform, the drug comprising doxorubicin. This invention constructs a highly efficient multi-metal electronic synergistic network nanoplatform, systematically achieving efficient synergy and cascade enhancement of multiple treatment modalities, forming a multi-mechanism synergistic therapeutic system of "photothermal-chemotherapy-chemokinetics-immunoactivation".

Description

Technical Field

[0001] This invention relates to the field of biomedicine, and in particular to a multi-metal synergistic network nanoplatform, its preparation method, and its applications. Background Technology

[0002] Traditional nanocarriers for tumor therapy generally suffer from problems such as single function, poor targeting, treatment resistance, and inability to monitor efficacy in real time. Although manganese dioxide carriers have attracted attention due to their pH-responsive degradability and good biocompatibility, their single therapeutic modality limits their efficacy. In recent years, research has attempted to improve the performance of nanocarriers through functional composites. For example, some studies have constructed copper-manganese hybrid nanogels for MRI-guided photothermal and chemikinetic therapy. Other work has developed a CuS / CuO2 composite nanozyme system, which utilizes near-infrared light to trigger a cascade reaction to enhance bactericidal effects. Other iron / manganese co-doped nanostructures (such as MXene) have also been shown to be useful for multimodal imaging and synergistic therapy.

[0003] With the continuous development of social technology, research on anti-tumor treatment methods has become increasingly in-depth, and the strategy of combining multimodal imaging with synergistic therapy has become a hot topic of concern both domestically and internationally. This strategy aims to visualize the tumor treatment process and achieve closed-loop management of "diagnosis-treatment-monitoring". However, current technology still faces a key challenge: how to construct a nanoplatform that can organically integrate multiple functions such as drug loading and controlled release, efficient photothermal conversion, chemokinetic therapy, and multimodal imaging, and achieve synergistic enhancement between functional units, rather than simple superposition. At the material design and synthesis level, the following main problems exist: First, nanoparticles are prone to aggregation, surface passivation, or catalytic inactivation, which not only directly affects the therapeutic effect but may also cause biosafety issues; at the same time, insufficient metal loading in the nanozyme matrix will also limit its catalytic activity. In addition, unintended interactions may occur between different metal centers, triggering non-selective reactions or generating undesirable byproducts, thereby reducing the specificity of the reaction and the overall catalytic efficiency. In addition, for carriers with hollow structures, how to achieve controllable doping and precise positioning of multiple active components (such as specific metal ions and nanoparticles) within a limited internal space, while simultaneously maintaining the integrity of the carrier structure itself and the dispersion stability of the system, is a core technical challenge that must be solved to build high-performance, multifunctional nanoplatforms. Summary of the Invention

[0004] To address the shortcomings of existing technologies, this invention provides a multi-metal synergistic network nanoplatform, characterized in that the multi-metal synergistic network nanoplatform comprises particles and a framework, the particles comprising copper-containing particles and iron elements, the framework comprising manganese dioxide (MnO2), and the particles being doped into the framework.

[0005] In one embodiment, the copper-containing particles comprise copper sulfide (CuS), and the iron element comprises Fe. 3+ The manganese dioxide is hollow manganese dioxide (HMnO2).

[0006] In one embodiment, the copper sulfide is supported on the surface and in the cavity of the hollow manganese dioxide, and the Fe... 3+ Ions are doped into the hollow manganese dioxide.

[0007] A second aspect of the present invention also provides a method for preparing the above-mentioned multi-metal synergistic network nanoplatform, comprising the following steps: Preparation of the framework (HMnO2): Cyclohexane, n-hexanol and Triton X-100 were mixed and stirred. Ammonia and water were added and stirred. Tetraethyl orthosilicate and 3-aminopropyltriethoxysilane were added and stirred to obtain silica nanospheres. The silica nanospheres were washed and dispersed in water. The mixture was stirred and potassium permanganate aqueous solution was added dropwise. The mixture was reacted, centrifuged and washed, and etched in sodium carbonate solution to obtain the framework. Preparation of iron-doped framework (Fe / HMnO2): The framework was dispersed in water, ferric nitrate aqueous solution was added, the reaction was stirred, the product was collected by centrifugation and washed to obtain the iron-doped framework; Preparation of the nanoplatform (CuS@Fe / HMnO2): The iron-doped framework was dispersed in water, copper chloride aqueous solution was added, stirred, thioacetamide aqueous solution was added, the mixture was heated under reflux, cooled, the product was collected by centrifugation, and washed to obtain the nanoplatform.

[0008] In one embodiment, in the preparation of the skeleton, the following dosage ratios are used: cyclohexane: n-hexanol: Triton X-100: ammonia: tetraethyl orthosilicate: 3-aminopropyltriethoxysilane: potassium permanganate: (10~50) mL: (1~10) mL: (1~10) mL: (0.2~1) mL: (0.1~0.5) mL: (0.1~0.5) mL: (300~1200) mg.

[0009] In one embodiment, in the preparation of the skeleton, the following dosage ratio is used: cyclohexane: n-hexanol: Triton X-100: ammonia: tetraethyl orthosilicate: 3-aminopropyltriethoxysilane: potassium permanganate is 22.5 mL: 5.4 mL: 5.3 mL: 0.75 mL: 0.5 mL: 0.1 mL: 600 mg.

[0010] In one embodiment, the concentration of potassium permanganate in the preparation of the skeleton is 5~20 mg / mL.

[0011] In one embodiment, the concentration of potassium permanganate in the preparation of the skeleton is 10 mg / mL.

[0012] In one embodiment, the concentration of the sodium carbonate solution is 1-5 mM during the preparation of the skeleton.

[0013] In one embodiment, the concentration of the sodium carbonate solution is 2 mM during the preparation of the skeleton.

[0014] In one embodiment, the stirring reaction time during the preparation of the skeleton is 6-24 hours.

[0015] In one embodiment, the stirring reaction time during the preparation of the skeleton is 12 hours.

[0016] In one embodiment, the reaction time during the preparation of the skeleton is 6-24 hours.

[0017] In one embodiment, the reaction time during the preparation of the skeleton is 12 hours.

[0018] In one embodiment, the centrifugation time during the preparation of the skeleton is 1 to 10 minutes.

[0019] In one embodiment, the centrifugation time during the preparation of the skeleton is 5 minutes.

[0020] In one embodiment, during the preparation of the skeleton, the etching is performed in an oil bath for 6 to 24 hours.

[0021] In one embodiment, during the fabrication of the skeleton, the etching is performed by etching in an oil bath for 12 hours.

[0022] In one embodiment, in the preparation of the iron-doped framework, the ratio of the framework to the ferric nitrate is (10~30) mg: (0.01~0.1) mmol.

[0023] In one embodiment, in the preparation of the iron-doped framework, the ratio of the framework to the ferric nitrate is 20 mg to 0.05 mmol.

[0024] In one embodiment, the concentration of the ferric nitrate aqueous solution is 1~10 mM during the preparation of the iron-doped framework.

[0025] In one embodiment, the concentration of the ferric nitrate aqueous solution is 5 mM during the preparation of the iron-doped framework.

[0026] In one embodiment, the stirring reaction time in the preparation of the iron-doped framework is 1-5 hours.

[0027] In one embodiment, the stirring reaction time in the preparation of the iron-doped framework is 4 hours.

[0028] In one embodiment, the stirring reaction temperature is 50~100°C during the preparation of the iron-doped framework.

[0029] In one embodiment, the stirring reaction temperature is 80°C during the preparation of the iron-doped framework.

[0030] In one embodiment, the centrifugation time is 1 to 10 minutes during the preparation of the iron-doped framework.

[0031] In one embodiment, the centrifugation time is 5 minutes during the preparation of the iron-doped framework.

[0032] In one embodiment, in the preparation of the nanoplatform, the iron-doped framework: copper chloride: thioacetamide is (10~50) mg: (0.01~0.04) mmol: (0.05~0.25) mmol in the following proportions.

[0033] In one embodiment, during the preparation of the nanoplatform, the iron-doped framework: copper chloride: thioacetamide is in the following proportions: 20 mg: 0.02 mmol: 0.2 mmol.

[0034] In one embodiment, the concentration of the copper chloride aqueous solution is 5-20 mM during the preparation of the nanoplatform.

[0035] In one embodiment, the concentration of the copper chloride aqueous solution is 10 mM during the preparation of the nanoplatform.

[0036] In one embodiment, the concentration of the thioacetamide aqueous solution is 5-25 mM during the preparation of the nanoplatform.

[0037] In one embodiment, the concentration of the thioacetamide aqueous solution is 20 mM during the preparation of the nanoplatform.

[0038] In one embodiment, the heating reflux reaction temperature is 50~80°C during the preparation of the nanoplatform.

[0039] In one embodiment, the heating reflux reaction temperature is 70°C during the preparation of the nanoplatform.

[0040] In one embodiment, the heating reflux reaction time in the preparation of the nanoplatform is 1-4 hours.

[0041] In one embodiment, the heating reflux reaction time in the preparation of the nanoplatform is 1 hour.

[0042] In one embodiment, the centrifugation time in the preparation of the nanoplatform is 1 to 10 minutes.

[0043] In one embodiment, the centrifugation time is 5 minutes during the preparation of the nanoplatform.

[0044] A third aspect of the present invention also provides a medicament for treating tumors, the medicament comprising a drug and the aforementioned multi-metal synergistic network nanoplatform, the drug being loaded onto the multi-metal synergistic network nanoplatform.

[0045] A fourth aspect of the present invention also provides a method for preparing the above-mentioned medicament for treating tumors, comprising the following steps: The multi-metal synergistic network nanoplatform was dispersed in water, a drug was added, the mixture was shaken in the dark, and the product was collected by centrifugation to obtain the drug-loaded nanoplatform. The drugs mentioned include doxorubicin.

[0046] In one embodiment, the multi-metal synergistic network nanoplatform: the drug is (5~20): (1~10) by mass ratio.

[0047] In one embodiment, the ratio of the multi-metal synergistic network nanoplatform to the drug is 1:1 by mass.

[0048] In one embodiment, the light-shielding oscillation time is 6~24h.

[0049] In one embodiment, the light-shielding oscillation time is 12 hours.

[0050] In one embodiment, the centrifugation time is 1 to 10 minutes.

[0051] In one embodiment, the centrifugation time is 5 minutes.

[0052] In addition, the present invention also provides the application of the above-mentioned multi-metal synergistic network nanoplatform or the multi-metal synergistic network nanoplatform obtained by the above preparation method in the preparation of drugs for treating tumors.

[0053] Compared with the prior art, the present invention has the following beneficial effects: This invention, based on a cross-scale interface engineering strategy, constructs a highly efficient multi-metal electronic synergistic network, significantly improving the performance of catalytic kinetic therapy (CDT). Its core mechanism lies in the cascade synergy and strong electronic coupling among the three metal cycles of Fe, Mn, and Cu: First, Fe... 3+ / Fe2+ The cycle, acting as the backbone of the Fenton reaction, continuously catalyzes the production of ·OH from H2O2 in the tumor microenvironment; secondly, Mn... 4+ / Mn 2+ The loop consumes H + This broadens the active pH window and improves substrate utilization, providing an auxiliary catalytic pathway; most importantly, Cu... + / Cu 2+ The loop acts as an "electronic transfer station," efficiently reducing Fe through strong interface coupling. 3+ With Mn 4+ This greatly accelerates the regeneration of active centers, breaks through the kinetic bottleneck of the traditional Fenton reaction, and achieves a doubling of the ·OH yield. To achieve the above synergistic mechanism, this invention employs a step-by-step controllable preparation strategy to construct a multifunctional nanocarrier: using monodisperse hollow MnO2 as the carrier substrate, Fe is incorporated through gradient doping. 3+ Atomic-level embedding into its lattice initially establishes a Mn / Fe electron transfer pathway; further, CuS is epitaxially grown via heterojunction bonding, forming stable SO-Fe interfacial chemical bonds and constructing a low-resistance heterojunction to ensure efficient electron transport between the three metal active sites. Based on this nanostructure, the system achieves efficient synergy and cascade enhancement of multiple therapeutic modalities.

[0054] On the one hand, the photothermal effect of CuS composition and Fe 3+ The Fenton reaction is organically combined with local heating, which significantly accelerates the reaction kinetics, forming a synergistic therapeutic effect of "photothermal-chemokinetic kinetics". On the other hand, the carrier responsively releases doxorubicin (DOX) in the tumor microenvironment, while simultaneously consuming glutathione (GSH) and promoting Mn 2+ with Fe 2+ This process further enhances the efficiency of bimetallic Fenton therapy, ultimately forming a multi-mechanism synergistic treatment system of "photothermal-chemotherapy-chemokinetics-immune activation".

[0055] Furthermore, this system possesses integrated diagnostic and therapeutic capabilities, enabling real-time monitoring of nanoparticle enrichment at tumor sites via magnetic resonance imaging (MRI), guiding the timing of photothermal therapy and simultaneously assessing efficacy, thus achieving closed-loop management of "diagnosis-treatment-monitoring." Regarding safety, its functional activation is highly dependent on tumor microenvironment characteristics (such as acidic pH, high GSH, and high H2O2), remaining inert in normal tissues and significantly reducing off-target toxicity. In terms of preparation technology, this method offers advantages such as readily available raw materials, mild conditions, simple steps, and high yield, demonstrating good reproducibility and scalability, laying a solid foundation for subsequent clinical translation. This project not only reveals the electron migration and recycling mechanism of multi-metal synergistic enhancement of CDT from a theoretical perspective but also provides a systematic material basis and technical path for constructing an efficient and intelligent collaborative diagnostic and therapeutic platform through cross-scale material design and functional integration. Finally, regarding the preparation technology, the method features readily available raw materials, mild conditions, simple steps, and high yield, demonstrating good process reproducibility and scalability, laying a solid foundation for subsequent industrial production and clinical translation. Attached Figure Description

[0056] Figure 1 This is a transmission electron microscope (TEM) image of HMnO2. Figure 2 (A) Time-temperature graphs of CuS@Fe / HMnO2 with different powers under NIR irradiation; (B) Time-temperature graphs of CuS@Fe / HMnO2 with different concentrations under NIR irradiation; (C) Time-temperature graphs of cyclic heating and cooling; (D) Time constant graph. Figure 3 (A) is the UV-Vis spectrum of TMB and H2O2 catalyzed by CuS@Fe / HMnO2; (B) is the concentration of dissolved oxygen of CuS, HMnO2, CuS@Fe / HMnO2+NIR, and CuS@Fe / HMnO2 at different times. Figure 4 (A) is the Michaelis-Menten kinetic analysis diagram; (B) is the Lineweaver-Burk diagram used to study the POD enzyme activities of HMnO2, Fe / HMnO2, and CuS@Fe / HMnO2 under H2O2 substrate conditions. Figure 5 (A) is the residual rate of GSH under different pH conditions; (B) is the residual rate of GSH in different samples at pH=5.2; (C) is the residual rate of GSH in different concentrations of CuS@Fe / HMnO2 at pH=5.2; (D) is the residual rate of GSH at different times. Figure 6 The cumulative release rate of CuS@Fe / HMnO2@DOX under different release conditions. Detailed Implementation

[0057] The purpose of this invention is to provide a novel composite nanomaterial and its preparation method, aiming to solve key problems such as the efficient integration of multifunctional nanocomponents, overcoming the limitations of single imaging modes, and realizing visualized synergistic therapy in response to the tumor microenvironment. Specifically, this invention constructs a nanoplatform based on the synergistic effect of the Mn / Fe / Cu trimetallic compounds, which enhances chemokinetic therapy (CDT). Leveraging the properties of each component, a multi-metal cascade amplification synergistic mechanism is designed, enabling photothermal therapy (PTT), CDT, and chemotherapy to not only function independently but also overcome the problem of low catalytic efficiency in the tumor environment, effectively reversing the inhibitory effect of the tumor microenvironment (TME) and producing a super-superimposed synergistic killing effect of "1+1+1>3". This platform enables intelligent controlled release of therapeutic units at the tumor site, thereby maximizing therapeutic efficacy; simultaneously, combined with multimodal imaging technology, it can achieve integrated closed-loop management of "diagnosis-treatment-monitoring".

[0058] To facilitate understanding of the present invention, a more complete description will be given below with reference to the accompanying drawings. Preferred embodiments of the invention are shown in the drawings. However, the invention can be implemented in many different forms and is not limited to the embodiments described herein. Rather, these embodiments are provided to provide a thorough and complete understanding of the disclosure of the invention.

[0059] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention pertains. The terminology used herein in the description of the invention is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention. The term "and / or" as used herein includes any and all combinations of one or more of the associated listed items.

[0060] Unless otherwise specified, all reagents, materials, and equipment used in this embodiment are commercially available; unless otherwise specified, all test methods are conventional test methods in this field.

[0061] Example This invention provides a method for preparing a multi-metal synergistic network nanoplatform, comprising the following steps: 1. Synthesis of HMnO2 Hollow manganese dioxide was prepared using a template method. First, appropriate amounts of cyclohexane, n-hexanol, and Triton X-100 were mixed and stirred thoroughly to form a homogeneous system. Then, ammonia and ultrapure water were added sequentially, and the mixture was stirred continuously at room temperature. After homogeneity, tetraethyl orthosilicate and 3-aminopropyltriethoxysilane were added, and the reaction was continued for a specified time. After the reaction, the obtained silica nanospheres were washed three times sequentially with anhydrous ethanol and ultrapure water to remove residual reagents. The purified silica was redispersed in ultrapure water, and potassium permanganate aqueous solution was slowly added dropwise under stirring, reacting at room temperature for a certain time. After the reaction was complete, the core-shell structured SiO2@MnO2 was obtained by centrifugation and washing. Finally, the silica template was removed by etching in sodium carbonate solution to obtain HMnO2.

[0062] 2. Synthesis of Fe / HMnO2 The obtained hollow manganese dioxide was dispersed in ultrapure water and mixed with ferric nitrate aqueous solutions of different concentrations. The mixture was stirred and reacted at a certain temperature for a specified time, allowing Fe... 3+ The Fe / HMnO2 composite material was fully incorporated into the MnO2 framework. After the reaction was complete, the product was collected by centrifugation and washed three times with ultrapure water to remove unbound iron ions, thus obtaining the Fe / HMnO2 composite material.

[0063] 3. Synthesis of CuS@Fe / HMnO2 A suitable amount of Fe / HMnO2 was redispersed in deionized water, and a copper chloride aqueous solution of a certain concentration was added. The mixture was stirred continuously to allow Cu to dissolve. 2+ It is fully adsorbed onto the material surface and within the pores. Subsequently, an aqueous solution of thioacetamide is slowly added under stirring. After thorough mixing, the reaction system is transferred to a round-bottom flask and heated under reflux in an oil bath. During this process, thioacetamide decomposes to release S. 2- , with adsorbed Cu 2+ The reaction generated CuS nanoparticles, which were deposited in situ on a Fe / HMnO2 support. After the reaction was completed, the mixture was naturally cooled to room temperature, and the product was collected by centrifugation and washed alternately with deionized water and ethanol to finally obtain the CuS@Fe / HMnO2 nanocomposite.

[0064] 4. Synthesis of CuS@Fe / HMnO2@DOX CuS@Fe / HMnO2 nanomaterials were dispersed in an aqueous solution, and a certain concentration of doxorubicin aqueous solution was added. The mixture was shaken at room temperature in the dark for a certain period of time to allow the drug molecules to be fully loaded into the nanocarrier. Finally, the drug-loaded nanoparticles were collected by centrifugation to obtain CuS@Fe / HMnO2@DOX.

[0065] Example 1 Preparation of HMnO2: Hollow manganese dioxide was prepared using a template method. First, 22.5 mL of cyclohexane, 5.4 mL of n-hexanol, and 5.3 mL of Triton X-100 were mixed and stirred thoroughly to form a homogeneous system. Then, 0.75 mL of 28% ammonia and 1 mL of ultrapure water were added sequentially, and the mixture was stirred continuously at room temperature. After homogeneity, 0.5 mL of tetraethyl orthosilicate and 0.10 mL of 3-aminopropyltriethoxysilane were added, and the reaction was continued for 12 hours. After the reaction, the obtained silica nanospheres were washed three times sequentially with anhydrous ethanol and ultrapure water to remove residual reagents. The purified silica was redispersed in ultrapure water, and potassium permanganate aqueous solution (60 mL, 10 mg / mL) was slowly added dropwise under stirring, and the reaction was carried out at room temperature for 12 hours. After the reaction was complete, the core-shell structured SiO2@MnO2 was obtained by centrifugation and washing. Finally, the obtained nanomaterials were etched and the silica template was removed by stirring in a sodium carbonate solution (2 mM) at 60°C for 12 h. After centrifugation and washing, HMnO2 was obtained.

[0066] like Figure 1 The transmission electron microscopy (TEM) images show that hollow nanoparticles can be obtained, indicating that they can efficiently load drugs.

[0067] Example 2 Preparation of Fe / HMnO2: 20 mg of hollow manganese dioxide was dispersed in 40 mL of ultrapure water, and ferric nitrate aqueous solution (5 mM, 10 mL) was added dropwise. The mixture was then stirred at 80 °C for 4 hours. The product was collected by centrifugation and washed three times with ultrapure water to remove unbound iron ions, yielding the Fe / HMnO2 composite material.

[0068] Example 3 Preparation of CuS@Fe / HMnO2: 20 mg Fe / HMnO2 was redispersed in deionized water, and copper chloride aqueous solution (10 mM, 2 mL) was added. The mixture was stirred continuously until CuS@Fe / HMnO2 was dissolved in water. 2+ The adsorption was fully absorbed onto the material surface and within the pores. Subsequently, 10 mL of thioacetamide aqueous solution (20 mM) was slowly added under stirring. After mixing thoroughly, the reaction system was transferred to a round-bottom flask and heated under reflux in an oil bath at 70 °C for 1 hour. The mixture was then naturally cooled to room temperature. The product was collected by centrifugation and washed alternately with deionized water and ethanol to finally obtain CuS@Fe / HMnO2 nanocomposite.

[0069] Example 4 Preparation of CuS@Fe / HMnO2@DOX: 5 mg of CuS@Fe / HMnO2 nanomaterials were dispersed in 5 mL of aqueous solution, and 5 mg of doxorubicin was added. The mixture was shaken overnight at room temperature in the dark to allow the drug molecules to be fully loaded into the nanocarrier. Finally, the drug-loaded nanoparticles were collected by centrifugation to obtain CuS@Fe / HMnO2@DOX.

[0070] Implementation effect evaluation 1. Evaluation of the photothermal performance of CuS@Fe / HMnO2 CuS@Fe / HMnO2 was dissolved in water to prepare different concentrations (0, 50, 100, 150, and 200 μg / mL). 200 μL of each concentration was placed in a 96-well plate, and the entire sample surface was uniformly illuminated with a light source. Temperature changes were recorded every 10 seconds for 5 minutes using a temperature sensor. 100 μL of a 150 μg / mL sample was also placed in a 96-well plate, and different power light sources (0.5, 0.8, and 1.0 W / cm²) were used for illumination. 2 The sample surface was uniformly irradiated, and the temperature change was recorded every 10 seconds for 5 minutes using a temperature sensor. 150 μL of a 150 μg / mL sample was placed in a 96-well plate, and then irradiated with 1.0 W / cm² water. 2 The light source was evenly irradiated onto the entire sample surface, and the temperature change was recorded every 10 seconds for 5 minutes using a temperature sensor. Then the light source was turned off, and the recording was continued for another 5 minutes. This heating was repeated 4 times, each time for 5 minutes.

[0071] The results are as follows Figure 2 As shown, CuS@Fe / HMnO2 aqueous solutions of different concentrations were subjected to different wavelengths at 808 nm and 1.0 W / cm². -2 After irradiation for 5 minutes, the temperature reached over 50℃ at a concentration of 150 μg / mL. This indicates that increasing the concentration of CuS@Fe / HMnO2 leads to a corresponding increase in temperature. Furthermore, CuS@Fe / HMnO2 exhibited the same results at different power levels, demonstrating its excellent photothermal properties. Therefore, an irradiation concentration of 150 μg / mL and a power of 1.0 W / cm² were used. 2 Subsequent experiments were conducted using light intensity at 808 nm and 1.0 W / cm². To investigate the photothermal cycling stability of CuS@Fe / HMnO₂ over a short period, subsequent experiments were performed. -2 Under the conditions of 5 on-off cycles (5 min heating / 5 min natural cooling each time), the peak height and half-peak width remained almost unchanged, confirming that the material maintained structural integrity and stable performance under multiple photothermal excitations.

[0072] 2. Peroxidase (POD) activity To evaluate the peroxidase (POD) catalytic performance of the material, Michaelis-Menten enzyme kinetics experiments were performed using TMB as a probe. First, TMB (250 μg / mL, 10 mL) was prepared using sodium acetate solution at pH 4.0, and hydrogen peroxide solution (10 mM, 10 mL) was prepared to achieve a nanomaterial suspension concentration of 15.6 μg / mL. The absorbance at 650 nm was measured using a UV-Vis spectrophotometer.

[0073] The results are as follows Figure 3 As shown in Figure A, in the presence of H₂O₂, CuS@Fe / HMnO₂ can efficiently catalyze the oxidation of colorless TMB to blue-green oxTMB, producing a significant absorption peak at 650 nm. Furthermore, CuS@Fe / HMnO₂ can induce a Fenton-like reaction and generate ·OH under acidic conditions without the addition of H₂O₂. When additional H₂O₂ is added, a stronger Fenton-like reaction is induced, generating more ·OH, indicating that this material possesses excellent catalytic activity.

[0074] like Figure 4 As shown, based on steady-state kinetic analysis, the CuS@Fe / HMnO2 nanozyme exhibits excellent enzyme-like catalytic efficiency at pH 4.0, with a maximum reaction rate (Vmax) as high as 1.280 × 10⁻⁶. -7 Ms -1 Meanwhile, the Michaelis constant (Km) is as low as 0.06218 mM. This data indicates that the material not only possesses extremely high intrinsic catalytic activity but also exhibits a tight binding and strong affinity with the substrate H₂O₂. Its performance far surpasses that of single (HMnO₂) and bimetallic (Fe / HMnO₂) systems, which stems from the successful construction of a highly efficient electron transfer network for synergistic catalysis by Fe, Mn, and Cu. In this network, Cu… + / Cu 2+ The cycle, as the core driving unit, can continuously and efficiently dissipate accumulated inert Fe. 3+ Reduced to active Fe 2+ This significantly accelerates the classical Fenton reaction cycle; simultaneously, Mn 4+ / Mn 2+ The cycle not only contributes additional Fenton-like reaction pathways, but its valence state changes can also mutually promote the Fe cycle. This cascade and synergy among multiple metals fundamentally solves the bottleneck of sluggish metal ion valence state cycling and easy deactivation of active centers in single or binary catalysts, achieving efficient capture and conversion of low concentrations of H2O2 in the tumor microenvironment, thus explaining its extraordinary catalytic kinetics at the mechanistic level.

[0075] 3. Catalase (CAT) activity The activity of catalase (CTA) was indirectly evaluated by analyzing the rate at which hydrogen peroxide in nanomaterials is converted into dissolved oxygen. First, oxygen-free water was prepared by purging with nitrogen. Then, the dissolved oxygen concentration in oxygen-free water containing the same concentration of different nanomaterials and hydrogen peroxide was measured over 10 minutes using a dissolved oxygen meter, with data recorded every 20 seconds.

[0076] The results are as follows Figure 3 As shown in Figure B, the CuS component alone exhibited only weak CAT activity, while HMnO2 showed a clear and measurable catalytic ability. However, most significantly, the CuS@Fe / HMnO2 obtained through precise structural composite showed a qualitative leap in CAT activity, with a 15.83 mg / mL increase in dissolved oxygen concentration. This not only significantly surpassed either single component (CuS or HMnO2) but also far exceeded the theoretical summation achievable through simple physical mixing. This conclusively proves that Fe... 3+ The doped CuS and hollow HMnO2 support are not functionally parallel, but rather exhibit a strong intrinsic synergistic catalytic effect through tight coupling at the atomic / nanoscale. To further reveal the multidimensional response characteristics of this synergistic system, we introduced near-infrared light irradiation under simulated therapeutic conditions. Under 808 nm laser excitation, the CAT activity of CuS@Fe / HMnO2 was further enhanced, reaching approximately 2.4 times that of HMnO2 under the same conditions. This phenomenon clearly indicates that the efficient photothermal conversion capability of the CuS component in the system does not function independently, but rather directionally enables and significantly amplifies the chemical kinetic catalytic process of the Fe / HMnO2 unit, achieving active coupling and bidirectional enhancement between the "photothermal-chemical kinetic" therapeutic modes.

[0077] In summary, CuS@Fe / HMnO2 exhibits exceptional catalytic performance that cannot be explained by the simple superposition of its components, whether under basic catalysis or under external energy excitation conditions. This strongly confirms that the unique heterostructure constructed in this invention successfully achieves a leap from a "functional set" to a "synergistic system," producing a disruptive enhancement effect of "1+1>>2."

[0078] 4. Glutathione peroxidase (GSH) activity To evaluate the glutathione (GSH) oxidase activity of the material, DNTB was used as a probe for measurement. First, GSH (5 mM) was prepared using PBS solutions with pH=5.2, pH=6.0, and pH=7.4, and DNTB solution (pH=8.0, 2 mM) was prepared. The nanomaterial PBS suspension (200 μg / mL, 100 μL) was mixed with 100 μL of GSH solution and reacted in a shaker at 37°C for a certain time (5 h). After the reaction was completed, the supernatant was collected by centrifugation, and 40 μL of 2 mM DNTB solution was added. Then, the solution was diluted with PBS to 400 μL and incubated in the dark for 15 min. The absorbance at 412 nm was then measured using a microplate reader.

[0079] The results are as follows Figure 5 As shown in Figure A, under neutral conditions, GSH in CuS@Fe / HMnO2 is almost not consumed, while under acidic conditions, the concentration of GSH decreases, and the OD value decreases. The assessment of the glutathione (GSH) consumption capacity further reveals the synergistic mechanism among the multi-metal components from the perspective of "tumor antioxidant defense breakdown." Figure 5 As shown in Figure B, this three-component material exhibits a significantly higher GSH depletion efficiency than single-component (CuS or HMnO2) and two-component (Fe / HMnO2) materials. This is attributed to the cascade reaction network it constitutes: HMnO2 depletes GSH through the reaction MnO2 + 2GSH + 2H+. + →Mn 2+ The reaction +GSSG + 2H2O directly consumes GSH and generates the catalytically active center Mn. 2+ Doped Fe 3+ Can be transmitted via 2Fe 3+ +2GSH→2Fe 2+ +GSSG+2H + The pathway simultaneously consumes GSH and regenerates Fe, the key species for the Fenton reaction, in situ. 2+ ; while Cu on the CuS surface 2+ It can also be reduced to Cu by GSH. + Highly active Cu is generated while consuming GSH. + These reactions are tightly coupled at the nano-interface, forming a self-driven synergistic cycle—the consumption of GSH continuously regenerates the necessary reduced metal ions (Fe) for Fenton-like reactions. 2+ Mn 2+ Cu + The high levels of reactive oxygen species (·OH) generated by these ion catalysis induce oxidative stress, which further consumes and interferes with the regeneration of intracellular GSH. The effectiveness of this mechanism has been systematically verified: GSH consumption exhibits a significant concentration-dependent effect. Figure 5 C) and time dependence ( Figure 5(D) After 6 hours, the residual GSH level can be as low as 3.6%, and the reaction is pH-dependent, with higher efficiency in acidic microenvironments. Therefore, this "multi-pathway, self-reinforcing" GSH depletion capability not only directly reduces the probability of ·OH being removed, but also greatly improves the efficiency of chemokinetic therapy by maintaining the circulation of catalytic active centers, becoming the key cornerstone for this nanoplatform to achieve multiple synergistic effects of "chemokinetic therapy-photothermal therapy-chemotherapy".

[0080] 5. DOX Release To systematically evaluate the drug-controlled release performance of the CuS@Fe / HMnO2@DOX nanocarrier, we conducted in vitro drug release experiments simulating the tumor microenvironment.

[0081] like Figure 6 As shown, this carrier exhibits excellent stability and synergistic release capability: under physiological pH=7.4 conditions, the cumulative release rate after 72 hours is only 23.8%, effectively preventing premature leakage; in a weakly acidic environment (pH=5.5), the release rate increases to 41.5%; and under pH=7.4+GSH conditions, the release rate reaches 1.5 times that of the acid-responsive group, confirming that the redox reaction of MnO2 and GSH is the core driving force for drug release. Crucially, when acidic and reducing conditions are combined (pH=5.5+GSH), the 24-hour release rate significantly increases to 75.8%, demonstrating the synergistic amplification effect of endogenous signals. Finally, under exogenous near-infrared light triggering, the full-function group (pH=5.5+GSH+NIR) achieves a release rate as high as 89.7% within 8 hours and ultimately reaches 94.3% after 72 hours, with its release efficiency significantly exceeding any single or dual-factor stimulation group. This "internal and external combined, multi-level response" strategy provides a powerful platform for achieving efficient synergistic treatment of tumors (chemotherapy / chemokinetics / photothermal therapy) and visual monitoring, demonstrating enormous potential for clinical application.

[0082] This invention provides a CuS / Fe co-doped hollow manganese dioxide nanoparticle drug carrier constructed based on a "pre-modulation-guided epitaxy" strategy and its application in integrated tumor diagnosis and treatment. This carrier, with precisely regulated hollow manganese dioxide as its core, not only possesses excellent biocompatibility but also exhibits multiple intelligent responses within the tumor microenvironment: it undergoes controlled degradation in response to the overexpression of glutathione (GSH) at the tumor site, thereby achieving precise drug release; the degradation process simultaneously generates Mn... 2+ It can be used as a highly efficient contrast agent for T1-weighted magnetic resonance imaging (MRI), providing real-time visual monitoring of the treatment process. Innovatively, Fe is incorporated through atomic-level gradient iron doping technology. 3+By introducing a manganese dioxide lattice, the material is endowed with highly efficient Fenton-like catalytic activity, specifically catalyzing the conversion of endogenous H2O2 in tumors into highly toxic ·OH free radicals, thus achieving chemokinetic therapy. Simultaneously, CuS nanostructures are uniformly constructed on the carrier surface and within the cavity using ligand-guided in-situ epitaxial growth technology. These nanostructures possess excellent photothermal conversion properties, generating localized high temperatures under near-infrared laser irradiation to achieve photothermal therapy and synergistically enhance drug controlled-release efficacy. Ultimately, the constructed CuS@Fe / HMnO2@DOX composite nanosystem, through synergistic coupling and cascade amplification among its functional units, achieves highly efficient synergy between MRI-guided photothermal therapy and chemokinetic therapy, forming a precise diagnostic-treatment-monitoring closed loop, representing an advanced design concept for a new generation of intelligent nanomedicine platforms.

[0083] The technical features of the above embodiments can be combined in any way. For the sake of brevity, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0084] The embodiments described above are merely illustrative of several implementations of the present invention, and while the descriptions are relatively specific and detailed, they should not be construed as limiting the scope of the invention patent. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of the present invention, and these all fall within the protection scope of the present invention. Therefore, the protection scope of this invention patent should be determined by the appended claims.

Claims

1. A multi-metal collaborative network nanoplatform, characterized in that, The multi-metal synergistic network nanoplatform includes particles and a framework. The particles include copper-containing particles and iron elements, and the framework includes manganese dioxide. The particles are doped into the framework.

2. The multi-metal collaborative network nanoplatform according to claim 1, characterized in that, The copper-containing particles include copper sulfide, and the iron element includes Fe. 3+ The manganese dioxide is hollow manganese dioxide.

3. The method for preparing the multi-metal synergistic network nanoplatform as described in any one of claims 1-2, characterized in that, Includes the following steps: Preparation of the framework: Cyclohexane, n-hexanol and Triton X-100 were mixed and stirred. Ammonia and water were added and stirred. Tetraethyl orthosilicate and 3-aminopropyltriethoxysilane were added and stirred to react to obtain silica nanospheres. The silica nanospheres were washed and dispersed in water. Potassium permanganate aqueous solution was added dropwise and reacted. After centrifugation and washing, the framework was etched in sodium carbonate solution. Preparation of iron-doped framework: The framework is dispersed in water, ferric nitrate aqueous solution is added, the reaction is stirred, the product is collected by centrifugation and washed to obtain the iron-doped framework. Preparation of the nanoplatform: The iron-doped framework was dispersed in water, copper chloride aqueous solution was added, stirred, thioacetamide aqueous solution was added, the mixture was heated under reflux, cooled, the product was collected by centrifugation, and washed to obtain the nanoplatform.

4. The preparation method according to claim 3, characterized in that, In the preparation of the skeleton, the following dosage ratio is used: cyclohexane: n-hexanol: Triton X-100: ammonia: tetraethyl orthosilicate: 3-aminopropyltriethoxysilane: potassium permanganate is (10~50) mL: (1~10) mL: (1~10) mL: (0.2~1) mL: (0.1~0.5) mL: (0.1~0.5) mL: (300~1200) mg.

5. The preparation method according to claim 3, characterized in that, In the preparation of the iron-doped framework, the ratio of the framework to the ferric nitrate is (10~30) mg: (0.01~0.1) mmol.

6. The preparation method according to claim 3, characterized in that, In the preparation of the nanoplatform, the iron-doped framework, copper chloride, and thioacetamide are in the following proportions: (10~50) mg, (0.01~0.04) mmol, and (0.05~0.25) mmol, respectively.

7. A drug for treating tumors, characterized in that, The drug for treating tumors includes a drug and the multi-metal synergistic network nanoplatform according to any one of claims 1-2, wherein the drug is loaded in the multi-metal synergistic network nanoplatform.

8. The method for preparing a medicament for treating tumors as described in claim 7, characterized in that, Includes the following steps: The multi-metal synergistic network nanoplatform was dispersed in water, a drug was added, the mixture was shaken in the dark, and the product was collected by centrifugation to obtain the drug-loaded nanoplatform. The drugs mentioned include doxorubicin.

9. The preparation method according to claim 8, characterized in that, According to the mass ratio, the multi-metal synergistic network nanoplatform: the drug is (5~20):(1~10).

10. The application of the multi-metal synergistic network nanoplatform as described in claims 1-2, or the multi-metal synergistic network nanoplatform obtained by the preparation method described in claims 3-6, in the preparation of drugs for treating tumors.

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