Carbon dot enhanced gold-based nanoflower material and preparation method and application thereof

Abstract

The application belongs to the technical field of biomedical materials and diagnosis and treatment integrated nanometer materials, and specifically discloses a carbon dot enhanced gold-based nanoflower material and a preparation method and application thereof. The application discloses a technology for reducing and inducing gold nanoparticles to aggregate by dopamine and alcohol heat sintering lanthanide metal cerium (Ce) doped carbon dots (CDCe), and synthesizing CDCe loaded gold-based nanoflower composite particles, which has the advantages of simple preparation method, low cost, good stability, high specific surface area and high biological safety, etc. Meanwhile, the technology combines the double advantages of gold nanoflowers and Ce doped carbon dots CDCe, exhibits significant fluorescence enhancement characteristics and high nanometer enzyme activity, and can realize the purpose of diagnosis-treatment integration, and has great potential application prospect in the fields of biomedicine, medical diagnosis and treatment, biological imaging, etc.

Description

Technical Field

[0001] This invention belongs to the field of biomedical materials and therapeutic nanomaterials technology, and specifically discloses a carbon dot-reinforced gold-based nanoflower material and its preparation method. Background Technology

[0002] Therapeutic materials are an indispensable part of the medical field, encompassing a wide range of tools and materials used for diagnosis, treatment, and monitoring. Compared to other therapeutic or imaging materials, therapeutic materials offer high precision and sensitivity, enabling accurate disease diagnosis and personalized treatment plans. Furthermore, some therapeutic materials are characterized by minimal invasiveness and rapid recovery, significantly enhancing the patient's healthcare experience.

[0003] However, therapeutic materials also face many challenges and limitations. On the one hand, the high cost of some therapeutic materials limits their widespread adoption and application in primary healthcare institutions. On the other hand, some therapeutic materials may have issues with biocompatibility, stability, and safety, requiring continuous improvement and optimization. In diagnosis, despite the rapid development of modern diagnostic technologies, problems remain regarding diagnostic accuracy, efficiency, and patient experience. In treatment, challenges exist in treatment effectiveness, side effects, and cost-effectiveness. Therefore, researching cost-effective, stable, biosafety-efficient, and high-performance therapeutic materials is a pressing issue facing the medical field.

[0004] Gold nanoparticles, with their high specific surface area, ease of modification, and good biocompatibility, have shown broad application prospects in biomedicine, catalysis, and drug delivery. However, the application of single gold nanoparticles in the medical field faces challenges due to their lack of sufficient robustness and less than ideal biocatalytic activity. Furthermore, the limited performance of gold nanoparticles and the difficulty in monitoring treatment processes restrict their application in the field of therapeutic materials.

[0005] Meanwhile, carbon dots, as an emerging nanomaterial, have attracted widespread attention due to their unique fluorescence properties and biocompatibility. Doping with elements such as Mn, Zn, Tb, Gd, and Fe not only enhances the fluorescence properties of carbon dots but also endows them with more functional characteristics, making them promising for applications in bioimaging, fluorescence sensing, and other fields. However, due to their small particle size, carbon dots are easily and rapidly metabolized in vivo, making long-term effects difficult to achieve; furthermore, their application is significantly limited because they possess only a single endonuclease activity.

[0006] Therefore, preparing diagnostic and therapeutic materials with both excellent stability and superior performance is a major challenge in the scientific research field. How to ensure that the materials remain stable in medical applications while giving full play to their dual functions of diagnosis and treatment has become a key issue that researchers urgently need to solve. Summary of the Invention

[0007] In view of this, the purpose of this invention is to address the problems existing in the prior art by providing a carbon dot-enhanced gold-based nanoflower material with significant fluorescence enhancement properties and highly efficient enzyme-like activity.

[0008] To achieve the above objectives, the present invention adopts the following technical solution:

[0009] The first technical objective of this invention is to provide a method for preparing carbon dot-reinforced gold-based nanoflower materials, the method specifically comprising the following steps:

[0010] (1) Prepare Tris buffer, then add HCl dropwise to adjust the pH, and add dopamine hydrochloride to prepare dopamine hydrochloride solution; then add chloroauric acid solution and stir to react, reduce and induce the aggregation of gold nanoparticles to form gold nanoflowers, and collect by centrifugation for later use.

[0011] (2) Dissolve o-phenylenediamine, dopamine and cerium nitrate in ethanol in sequence, and carry out an alcoholic reaction under high temperature and high pressure. Dialyze the resulting reaction solution to remove unreacted small molecules, and freeze dry.

[0012] (3) Weigh an appropriate amount of carbon dots and disperse them in a dimethyl sulfoxide solution. Slowly add AuNFs solution while stirring. Stir the reaction, centrifuge, and freeze dry to obtain the carbon dot-enhanced gold-based nanoflower composite particles.

[0013] Preferably, in step (1), hydrochloric acid is added dropwise to adjust the pH to 8.5, and the mass ratio of added dopamine hydrochloride to chloroauric acid is 2:1 to 1:2, and the mixture is stirred at room temperature for 9 to 12 hours.

[0014] Furthermore, in step (1), the stirring speed is 400-600 r / min; the centrifugation speed is 3500-6500 r / min; and the centrifugation time is 10-20 min.

[0015] Preferably, in step (2), the mass ratio of o-phenylenediamine, dopamine, and cerium nitrate is 0.5–1.5 mg: 0.5–1.5 mg: 0.25–1.5 mg, the volume of ethanol is 30 mL, the alcoholic reaction temperature is 140–220 °C, the reaction time is 10–14 h, the dialysis time is 12–24 h, and the freeze-drying time is 72 h.

[0016] Preferably, in step (3), the mass ratio of carbon dots to gold nanoflowers is 1:1 to 1:10, and the reaction time at room temperature is 2 to 12 hours.

[0017] The second technical objective of this invention is to provide a carbon dot-reinforced gold-based nanoflower material prepared by the above method, wherein the carbon dot-reinforced gold-based nanoflower material is a carbon dot-reinforced gold-based nanoflower composite particle (AuNFs@CDCe), and the size of the nanoflower composite particle is 110-180 nm.

[0018] The third technical objective of this invention is to provide the application of carbon dot-enhanced gold-based nanoflower materials prepared by the above method in biomedical materials and nanomedicine, enabling various applications such as medical imaging, diagnosis, and treatment.

[0019] Furthermore, antibacterial, anticancer, or growth-promoting drug particles can be grafted onto the carbon dot-reinforced gold-based nanoflower material, thereby expanding its wide range of clinical applications.

[0020] As can be seen from the above technical solution, compared with the prior art, the present invention provides a carbon dot-reinforced gold-based nanoflower material, its preparation method and application, which has the following excellent effects:

[0021] This invention utilizes a technique to synthesize gold-based nanoflower composite particles by reducing and inducing the aggregation of gold nanoparticles with dopamine and by ethanolothermal calcination of lanthanide metal cerium (Ce)-doped carbon dots (CDCe). This technique offers advantages such as simple preparation method, low cost, good stability, high specific surface area, and high biosafety. Furthermore, it combines the dual advantages of gold nanoflowers and Ce-doped carbon dots (CDCe), exhibiting significant fluorescence enhancement properties and highly efficient nanozyme activity. This enables integrated diagnostic and therapeutic applications and holds immense potential in biomedicine, medical diagnosis and treatment, and bioimaging. Attached Figure Description

[0022] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on the provided drawings without creative effort.

[0023] Figure 1 This is a TEM image of the AuNFs@CDCe nanomaterial in Example 1.

[0024] Figure 2 This is an elemental scan of the AuNFs@CDCe nanomaterial in Example 1.

[0025] Figure 3The fluorescence spectra of AuNFs and AuNFs@CDCe nanomaterials at the same concentration in Example 1 are shown.

[0026] Figure 4 The diagram shows the multi-endoenzyme performance of AuNFs and AuNFs@CDCe nanomaterials in Example 1, where: (a) elimination of hydroxyl radicals; (b) CAT-like activity. Detailed Implementation

[0027] The technical solutions in the embodiments of the present invention will be clearly and completely described below. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of the present invention.

[0028] The term "embodiment" used herein, as an example, is not necessarily to be construed as superior to or better than other embodiments. Performance testing in the embodiments of this application, unless otherwise specified, employs conventional testing methods in the art. It should be understood that the terminology used in this application is merely for describing particular implementations and is not intended to limit the scope of this disclosure.

[0029] Unless otherwise stated, the technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application pertains; other experimental methods and technical means not specifically mentioned herein refer to experimental methods and technical means commonly used by one of ordinary skill in the art.

[0030] To better illustrate the content of this application, numerous specific details are provided in the following detailed embodiments. Those skilled in the art should understand that this application can be implemented even without certain specific details. In the embodiments, some methods, means, instruments, and devices well known to those skilled in the art are not described in detail in order to highlight the main points of this application.

[0031] Without conflict, the technical features disclosed in the embodiments of this application can be combined arbitrarily, and the resulting technical solution belongs to the content disclosed in the embodiments of this application.

[0032] This invention discloses a method for preparing carbon dot-enhanced gold-based nanoflower materials with fluorescence enhancement effect and high-efficiency enzyme-like activity.

[0033] To better understand the present invention, the following embodiments are provided for further detailed description of the present invention, but they should not be construed as limiting the present invention. Any non-essential improvements and adjustments made by those skilled in the art based on the above-described invention are also considered to fall within the protection scope of the present invention.

[0034] Example 1: A method for preparing carbon dot-reinforced gold-based nanoflower materials

[0035] (1) Prepare 100 mL of Tris-HCl buffer with pH 8.5, add 0.12 g of dopamine hydrochloride to prepare a dopamine hydrochloride solution, then add 0.8 mL of chloroauric acid solution to make the final mass concentration 0.01%. Stir the reaction at room temperature for 9 h to reduce the gold nanoparticles, and collect them by centrifugation for later use.

[0036] (2) Weigh 0.08g o-phenylenediamine, 0.12g dopamine and 0.05g cerium nitrate (IV) and dissolve them in 30mL ethanol. The reaction is carried out at 160°C and high pressure for 6h. The reaction solution is dialyzed for 5h to remove unreacted small molecules and then freeze-dried to obtain dry carbon dot (CDCe) powder.

[0037] (3) Weigh 1 mg of carbon dot (CDCe) powder and dissolve it in dimethyl sulfoxide solution. Slowly add 2 mg of AuNFs solution while stirring and then stir for 6 h. After multiple centrifugation and washing, the carbon dot-enhanced gold-based nanoflower material can be obtained and stored at 4°C.

[0038] The size and morphology of the carbon dot-reinforced gold-based nanoflower material are as follows: Figure 1 As shown, by Figure 1 It is known that the size of the carbon dot-enhanced gold-based nanoflowers is 110-180 nm, and they exhibit a flower-like shape.

[0039] Elemental analysis of the carbon dot-reinforced gold-based nanoflower material is as follows: Figure 2 As shown, the distribution of Au and Ce elements proves the successful preparation of AuNFs@CDCe.

[0040] Example 2: A method for preparing carbon dot-reinforced gold-based nanoflower materials

[0041] (1) Prepare 100 mL of Tris-HCl buffer with pH 8.5, add 0.12 g of dopamine hydrochloride to prepare a dopamine hydrochloride solution, then add 0.8 mL of chloroauric acid solution to make the final mass concentration 0.01%. Stir the reaction at room temperature for 9 h to reduce the gold nanoparticles, and collect them by centrifugation for later use.

[0042] (2) Weigh 0.08g o-phenylenediamine, 0.12g dopamine and 0.05g cerium nitrate (IV) and dissolve them in 30mL ethanol. The reaction is carried out at 160°C and high pressure for 6h. The reaction solution is dialyzed for 5h to remove unreacted small molecules and then freeze-dried to obtain dry carbon dot (CDCe) powder.

[0043] (3) Weigh 0.5 mg of carbon dot (CDCe) powder and dissolve it in dimethyl sulfoxide solution. Slowly add 2 mg of AuNFs solution while stirring and stir for 3 h. After multiple centrifugation and washing, carbon dot-enhanced gold-based nanoflower material can be obtained and stored at 4°C.

[0044] Example 3: A method for preparing carbon dot-reinforced gold-based nanoflower materials

[0045] (1) Prepare 100 mL of Tris-HCl buffer solution with pH 8.5, add 0.12 g of dopamine hydrochloride to prepare a dopamine hydrochloride solution, then add 0.8 mL of chloroauric acid solution to make the final mass concentration 0.01%. Stir the reaction at room temperature for 9 h to reduce the gold nanoparticles, and collect them by centrifugation for later use.

[0046] (2) Weigh 0.08g o-phenylenediamine, 0.12g dopamine and 0.05g cerium nitrate (IV) and dissolve them in 30mL ethanol. The reaction is carried out under high temperature and high pressure at 180 degrees for 5h of alcoholic reaction. The reaction solution is dialyzed for 7h to remove unreacted small molecules and then freeze-dried to obtain dry carbon dot (CDCe) powder.

[0047] (3) Weigh 2 mg of carbon dot (CDCe) powder and dissolve it in dimethyl sulfoxide solution. Add 2 mg of AuNFs solution slowly while stirring and then stir for 6 h. After multiple centrifugation and washing, carbon dot-enhanced gold-based nanoflower material can be obtained and stored at 4°C.

[0048] The scope of this invention is not limited to the above embodiments; a combination of one or more embodiments can also achieve the purpose of this invention.

[0049] To further verify the superior effects of the present invention, the inventors also conducted the following experiments:

[0050] Experiment 1: To illustrate the fluorescence enhancement performance of AuNFs@CDCe

[0051] To investigate the fluorescence enhancement performance of AuNFs@CDCe, the 50ug / mL AuNFs and 50ug / mL AuNFs@CDCe solutions obtained in Example 1 were placed in a four-sided transparent quartz dish, and their fluorescence intensity was detected using a fluorescence spectrophotometer.

[0052] Depend on Figure 3 It can be seen that loading carbon dots can significantly enhance the fluorescence intensity of AuNFs@CDCe nanomaterials.

[0053] Experiment 2: To illustrate the hydroxyl radical scavenging activity of AuNFs@CDCe

[0054] To investigate the hydroxyl radical scavenging activity of AuNFs@CDCe, AuNFs and AuNFs@CDCe solutions of the same concentration obtained in Example 1 were placed in a four-sided transparent quartz dish. Acetic acid-sodium acetate buffer and ferrous sulfate solution were added, and H2O2 solution was slowly added. An equal amount of acetate-sodium acetate buffer was added to the control group. The reaction was carried out in the dark for 30 min. The fluorescence intensity at 450 nm was detected by excitation at 315 nm using a fluorescence spectrophotometer.

[0055] Depend on Figure 4 (a) shows that loading carbon dots can enhance the hydroxyl radical elimination performance of AuNFs@CDCe nanomaterials.

[0056] Experiment 3: Demonstrating the CAT-like activity of AuNFs@CDCe

[0057] To investigate the CAT-like properties of AuNFs@CDCe, AuNFs and AuNFs@CDCe solutions of the same concentration were added to pre-prepared H2O2 solution and PBS buffer, while the control group was added with an equal amount of PBS buffer. The dissolved oxygen content in the solution was detected using a liquid phase oxygen electrode.

[0058] Depend on Figure 4 (b) It can be seen that loading carbon dots can enhance the CAT performance of AuNFs@CDCe nanomaterials.

[0059] Experiment 4: To illustrate the preparation method of AuNFs@CDCe loaded with antibiotics

[0060] 20 mg of the anticancer drug doxorubicin (DOX) was dissolved in DMSO in a 50 mL beaker. After complete dissolution, 10 mg of AuNFs@CDCe obtained in Example 1 was added. The mixture was stirred at room temperature for 12 h and washed twice with DMSO to obtain AuNFs@CDCe drug-loaded nanoparticles grafted with the anticancer drug, thus endowing the carbon dot-enhanced gold-based nanoflower particles with multifunctionality.

[0061] Experiment 5: To illustrate the preparation method of AuNFs@CDCe loaded with antibiotics

[0062] 20 mg of the antibacterial drug vancomycin (Van) was dissolved in ethanol and placed in a 50 mL beaker. After complete dissolution, 10 mg of AuNFs@CDCe obtained in Example 1 was added. The mixture was stirred at room temperature for 3 h and washed twice with ethanol to obtain AuNFs@CDCe drug-loaded nanoparticles grafted with antibacterial drugs, thus endowing carbon dot-enhanced gold-based nanoflower particles with multifunctionality.

[0063] The above description of the disclosed embodiments enables those skilled in the art to make or use the invention. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the invention. Therefore, the invention is not to be limited to the embodiments shown herein, but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A method for preparing carbon dot-reinforced gold-based nanoflower materials, characterized in that, The carbon dot-reinforced gold-based nanoflower material is a carbon dot-reinforced gold-based nanoflower composite particle AuNFs@CDCe; the method specifically includes the following steps: (1) One-pot synthesis of gold nanoflowers by dopamine: Tris buffer was prepared, and then HCl was added dropwise to adjust the pH. Dopamine hydrochloride was added to prepare a dopamine hydrochloride solution. Then chloroauric acid solution was added and the reaction was stirred. Gold nanoflowers were synthesized by reduction and induction of aggregation by dopamine. The nanoflowers were collected by centrifugation for later use. (2) Synthesis of CDCe by alcohol thermal method: o-phenylenediamine, dopamine and cerium nitrate are dissolved in ethanol in sequence and subjected to alcohol thermal reaction under high temperature and high pressure. The resulting reaction solution is dialyzed to remove unreacted small molecules and then freeze-dried. The alcohol thermal reaction temperature is 140~220℃, and the reaction time is 10~14h; (3) Synthesis of AuNFs@CDCe: Weigh an appropriate amount of carbon dots prepared in step (2) and disperse them in dimethyl sulfoxide solution. Slowly add gold nanoflower solution while stirring. Stir the reaction, centrifuge and freeze dry to obtain the carbon dot-enhanced gold-based nanoflower composite particles. The mass ratio of carbon dots to gold nanoflowers added is 1:1 to 1:10, and the reaction time is 2 to 12 hours with stirring at room temperature.

2. The method for preparing carbon dot-reinforced gold-based nanoflower materials according to claim 1, characterized in that, In step (1), hydrochloric acid is added dropwise to adjust the pH to 8.5, and the mass ratio of added dopamine hydrochloride to chloroauric acid is 2:1 to 1:

2. The mixture is stirred at room temperature for 9 to 12 hours.

3. The method for preparing carbon dot-reinforced gold-based nanoflower materials according to claim 1 or 2, characterized in that, In step (1), the stirring speed is 400~600 r / min; the centrifugation speed is 3500~6500 r / min; and the centrifugation time is 10~20 min.

4. The method for preparing carbon dot-reinforced gold-based nanoflower materials according to claim 1, characterized in that, In step (2), the mass ratio of o-phenylenediamine, dopamine and cerium nitrate is 0.5~1.5mg:0.5~1.5mg:0.25~1.5mg, and the volume of ethanol is 30mL.

5. The method for preparing carbon dot-reinforced gold-based nanoflower materials according to claim 1 or 4, characterized in that, In step (2), the dialysis time is 12-24 hours and the freeze-drying time is 72 hours.

6. A carbon dot-reinforced gold-based nanoflower material prepared by the method described in claim 1, characterized in that, The carbon dot-enhanced gold-based nanoflower composite particles AuNFs@CDCe have a size of 110-180 nm.

7. The application of a carbon dot-reinforced gold-based nanoflower material prepared by the method of claim 1 or the carbon dot-reinforced gold-based nanoflower material of claim 6 in the preparation of biomedical materials.

8. The application according to claim 7, characterized in that, Antibacterial drug particles or anticancer drug particles are grafted onto the carbon dot-reinforced gold-based nanoflower material.

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