Preparation method and application of MXene-Au nanocomposite multifunctional antibacterial platform

Abstract

The invention discloses a preparation method and application of an MXene-Au nano composite material multifunctional antibacterial platform. According to the technical scheme, the preparation method is characterized in that a Ti3C2-Au nano composite material is constructed by adopting an electrostatic assembly method in combination with a seed growth method. An ultrathin Ti3C2 nanosheet is stripped from a Ti3AlC2MAX block, gold seeds are loaded by adopting an electrostatic self-assembly method after amination, and composite materials with different gold nanostructures are formed on the Ti3C2 nanosheet by adopting a seed growth method or an electrostatic adsorption effect. The method is simple in process and safe to operate, the synthesized composite material (Ti3C2-Au NWs) of gold nanowire arrays on the two faces of the Ti3C2 nanosheet can achieve sensitive SERS bacterial detection and bacterial adhesion, multiple functions of bacterial capture, SERS detection, photo-thermal sterilization and the like are achieved, and a direction is provided for clinically achieving rapid, sensitive and accurate detection and killing of pathogenic bacteria.

Description

Technical Field

[0001] The present invention belongs to the field of biomedical nanomaterials, and specifically relates to a preparation method and application of a MXene-Au nanocomposite multifunctional antibacterial platform. Background Art

[0002] With the rapid development of modern medicine and biomaterials technology, especially in-depth research in cross-fields such as nanotechnology, biomedicine, and sensor detection, biological infection control has become a very promising research direction. Since bacterial infections may cause a variety of health problems, including surgical site infections, wound infections, and other medical-related infections, timely and accurate detection and effective antibacterial treatment have become clinical solutions urgently needed. Especially in the case of increasingly serious bacterial resistance, traditional antibiotic therapy is not only time-consuming and has limited effects, but also often induces bacterial resistance, resulting in a gradual reduction in its application in clinical practice. Therefore, a multifunctional integrated platform for antibacterial detection and treatment has gradually become a frontier direction for antibacterial material research. At present, bacterial detection methods mainly include bacterial culture, PCR amplification detection, enzyme-linked immunosorbent assay, etc. Although these methods have high sensitivity and specificity, they are complex to operate, time-consuming and costly to detect, and are not suitable for real-time rapid detection needs. In contrast, the detection method based on surface enhanced Raman scattering (SERS) technology is gradually becoming a research hotspot for bacterial detection due to its advantages such as high sensitivity, short detection time, non-invasiveness, and wide application range. On this basis, photothermal therapy, as an emerging physical sterilization method, can use the absorption of light by nanomaterials to convert into heat, directly destroy the cell membrane structure of bacteria, and thus effectively kill pathogens. MXene materials have attracted widespread attention due to their excellent conductivity, hydrophilicity, rich surface chemical properties, and good compatibility with a variety of metal nanomaterials. In particular, Ti3C2 MXene materials, whose two-dimensional layered structure can provide a large area of ​​reaction sites, can be combined with metal nanoparticles to form nanocomposites, thus showing excellent performance in surface enhanced Raman scattering (SERS) detection and photothermal sterilization. The combination of Ti3C2 and gold nanoparticles, through electrostatic assembly and seed growth techniques, can not only enhance the antibacterial properties of the material, but also achieve triple functions in capture, detection and sterilization, simplifying the steps of detection and treatment. This multifunctional platform can sterilize through efficient photothermal action without increasing dependence on antibiotics, and combined with real-time detection of SERS signals, it provides a new and efficient infection control solution for the clinic.

[0003] Invention patent content

[0004] In view of the shortcomings of the prior art, the purpose of the present invention is to provide a new multifunctional antibacterial platform based on MXene-Au nanocomposite materials, which not only integrates the functions of capture, detection and killing, but also is applied to biological wound dressings to provide innovative solutions for the comprehensive treatment of bacterial infections. In order to achieve the above purpose, the patent of this invention adopts the following technical solutions:

[0005] (1) Preparation of Ti3C2-NH2: Ti3C2 was dissolved in ethanol and subjected to ultrasonic treatment for 30 min to make it uniformly dispersed. APTES was then added and stirred at room temperature for 48 h. To remove unbound APTES molecules, Ti3C2-NH2 was washed with a 50% ethanol / water mixture to obtain Ti3C2-NH2.

[0006] (2) Preparation of Ti3C2-Au seeds: Add excess gold seeds to the obtained Ti3C2-NH2 and disperse it evenly by ultrasonication for 0.5 h. Then stir it at 400 rpm for 12 h. After the reaction is completed, wash it with a 50% ethanol / water mixture to obtain Ti3C2-Auseeds.

[0007] (3) Preparation of Ti3C2-Au NWs: Anhydrous ethanol and Ti3C2-Au seeds were added to water and ultrasonicated for 20 min to make them evenly dispersed. Then, p-Mercaptobenzoic acid (MBA), ascorbic acid (AA), and HAuCl4 solution were added under stirring. After stirring for 1 min, the mixture was allowed to grow for 15 min. After the reaction was completed, the Ti3C2-Au NWs were washed with a 50% ethanol / water mixture to obtain the NWs.

[0008] (4) Preparation of Ti3C2-Au NRs: Au NRs solution was added to the synthesized Ti3C2-Au seed and stirred for 12 h. The mixture was then washed three times with ethanol water to obtain Ti3C2-Au NRs.

[0009] (5) Preparation of Ti3C2-Au NPs: Anhydrous ethanol and Ti3C2-Au seeds were added to water and ultrasonicated for 20 min to disperse them evenly. Then, ascorbic acid (AA) and HAuCl4 solution were added under stirring. The mixture was rotated at a medium speed for 15 min and then washed with ethanol water to obtain Ti3C2-Au NPs.

[0010] Furthermore, the concentration of the APTES is 1 to 5 mg / L.

[0011] Furthermore, the concentration of the p-mercaptobenzoic acid is 0.5-10 mM.

[0012] Furthermore, the concentration of the ascorbic acid is 0.5-0.5M.

[0013] Furthermore, the concentration of HAuCl4 is 1-50 mM.

[0014] Furthermore, the concentration of the Ti3C2-Au seeds is 1 to 20 mg / mL.

[0015] Furthermore, a composite material of gold nanowire arrays on both sides of Ti3C2 nanosheets (Ti3C2-AuNWs) was synthesized.

[0016] Beneficial effects of the invention patent:

[0017] The present invention can achieve high photothermal conversion efficiency by regulating the Ti3C2-Au morphology, and the materials have good photothermal stability and can be used for the research of photothermal antibacterial therapy.

[0018] The Ti3C2-Au NWs material synthesized by the present invention has dense nano tentacles that can closely contact bacteria. Because the substrate is soft Ti3C2, the material exhibits natural curvature and can better wrap bacteria. Strong adhesion is generated through a large number of contacts, and Escherichia coli and Staphylococcus aureus can be captured.

[0019] The AuNWs of the Ti3C2-Au NWs material synthesized by the present invention tend to gather at the head and form more SERS hot spots, which can achieve a higher SERS effect and has its own internal standard molecule MBA, thus realizing sensitive detection of characteristic peaks of Escherichia coli and Staphylococcus aureus.

[0020] The multifunctional antibacterial platform of Ti3C2-Au nanocomposite materials developed in the present invention provides a direction for the rapid, sensitive and accurate detection and killing of pathogens in clinical practice, and provides an innovative solution for the comprehensive treatment of bacterial infections. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 This is the SEM image of Ti3C2 nanosheets and the gold seeds attached to them.

[0022] Figure 2 SEM characterization of (a, b) Ti3C2-NWs; (c) Ti3C2-NRs; (d) Ti3C2-NPs.

[0023] Figure 3 (ab) SEM images of Ti3C2-AuNWs after incubation with E. coli; (cd) SEM images of Ti3C2-Au NPs after incubation with E. coli; (ef) SEM images of Ti3C2-AuNRs after incubation with E. coli.

[0024] Figure 4 (a) 10 8SERS spectrum of Escherichia coli on silicon wafer; (b) 10 8 SERS spectra of CFU / mL of Escherichia coli on Ti3C2-AuNWs.

[0025] Figure 5 (a) Temperature curve of Ti3C2-AuNWs irradiated with 1064nm laser for 10min and then turned off the laser. (b) Linear relationship between -lnθ and time obtained from e.

[0026] Figure 6 Infrared thermal imaging photos of Ti3C2-AuNWs with different concentrations.

[0027] Figure 7 The Ti3C2-Au composites with different concentrations were prepared with or without near-infrared radiation (1064 nm, 1.0 W / cm 2 Bacterial plate image of Escherichia coli treated with 4% paraformaldehyde (5% paraformaldehyde) for 10 minutes.

[0028] Figure 8 The wound healing status of mice under different conditions from 1 to 7 days. DETAILED DESCRIPTION

[0029] The present invention will be further described below in conjunction with the accompanying drawings and embodiments, so that the above contents can be better understood.

[0030] Example 1: Synthesis of Ti3C2-AuNWs: 450 μL of anhydrous ethanol and 50 μL of 1 mg mL -1 Ti3C2-AuNWs were ultrasonically dispersed for 20 minutes, and then 110 μl of 10 mM p-mercaptobenzoic acid (MBA), 17 μl of 0.492 M ascorbic acid (AA), and 67.5 μl of 50 mM HAuCl4 solution were added in sequence under stirring. After the addition, the mixture was stirred for 1 minute and then allowed to grow for 15 minutes. After the reaction was completed, the obtained product was washed three times with a 50% ethanol / water mixture to prepare Ti3C2-AuNWs.

[0031] Example 2: Synthesis of Ti3C2-AuNPs: 350 μL of anhydrous ethanol and 150 μL of 1 mg mL -1 Ti3C2-Au useds, after ultrasonication for 20 minutes, 17 μL 0.492M ascorbic acid and 67.5 μL 50mM HAuCl solution were added in sequence under stirring. After the addition, the mixture was stirred for 1 minute and then allowed to grow for 15 minutes. After the reaction was completed, the obtained product was washed three times with a 50% ethanol / water mixture to prepare Ti3C2-Au NPS.

[0032] Example 3: Synthesis of Ti3C2-Au NRs. First, prepare the gold seed. Add 0.25mL 0.010M HAuCl4 to 9mL 0.10M CTAB to prepare the gold solution. Quickly add the frozen, freshly prepared 0.60mL 0.010M NaBH4 to the stirred gold solution. The solution immediately changes from yellow to yellow-brown. After vigorous stirring for 10min, let it stand at 27℃ for 1.5h. Then, add 0.5mL 0.01M HAuCl4, 8.0mL 0.10M CTAB, 0.1M 0.01MAgNO3, 0.2mL 1MHCI, 80μL 0.1M ascorbic acid and 1ml of the prepared gold seed solution in turn. Gently invert the solution after adding each solution. Finally, let it stand at 27℃ for 20h and then centrifuge at 16000 rpm for 35min. The colored supernatant was transferred to a new centrifuge tube and purified again at the same centrifugation speed and time. The particles were collected and dispersed in ultrapure water for further use. Ti3C2-AuNRs composites were prepared by electrostatic interaction. 1 mL of Ti3C2 aqueous solution was added to 4 mL of AuNRs solution and ultrasonicated for 45 min. The dispersion was washed and centrifuged 3 times to remove excess non-adsorbed AuNRs, and the precipitate was dissolved in 500 mL of ultrapure water to prepare Ti3C2-AuNRs.

Claims

1. A preparation method and application of a MXene-Au nanocomposite multifunctional antibacterial platform, characterized in that The specific steps are as follows: (1) Preparation of Ti3C2-NH2: Ti3C2 was dissolved in ethanol (EtOH) and ultrasonicated for 30 min to make it evenly dispersed. 3-aminopropyltriethoxysilane (APTES) was then added and stirred at room temperature for 48 h. To remove unbound APTES molecules, Ti3C2-NH2 was washed with a 50% ethanol / water mixture to obtain Ti3C2-NH2. (2) Preparation of Ti3C2-Au seeds: Add excess gold seeds to the obtained Ti3C2-NH2 and disperse it evenly by ultrasonication for 0.5 h. Then stir it at 400 rpm for 12 h. After the reaction is completed, wash it with a 50% ethanol / water mixture to obtain Ti3C2-Au seeds. (3) Preparation of Ti3C2-Au NWs: Anhydrous ethanol and Ti3C2-Au seeds were added to water and ultrasonicated for 20 min to make them evenly dispersed. Then, p-Mercaptobenzoic acid (MBA), ascorbic acid (AA), and HAuCl4 solution were added under stirring. After stirring for 1 min, the mixture was allowed to stand for 15 min. After the reaction was completed, the Ti3C2-Au NWs were washed with a 50% ethanol / water mixture to obtain the Ti3C2-Au NWs. (4) Preparation of Ti3C2-AuNRs: AuNRs solution was added to the synthesized Ti3C2-Au seed and stirred for 12 h. The mixture was then washed three times with ethanol water to obtain Ti3C2-AuNRs. (5) Preparation of Ti3C2-AuNPs: Anhydrous ethanol and Ti3C2-Au seeds were added to water and ultrasonicated for 20 min to disperse them evenly. Then, 4-mercaptobenzoic acid (MBA), ascorbic acid (AA), and HAuCl4 solution were added under stirring. The mixture was rotated at a medium speed for 15 min and then washed with ethanol water to obtain Ti3C2-AuNPs.

2. The preparation method and application of a MXene-Au nanocomposite multifunctional antibacterial platform according to claim 1, characterized in that: The concentration of the APTES is 1-5 mg / L.

3. The preparation method and application of a MXene-Au nanocomposite multifunctional antibacterial platform according to claim 1, characterized in that: The concentration of the p-mercaptobenzoic acid is 0.5-100 mM.

4. The preparation method and application of a MXene-Au nanocomposite multifunctional antibacterial platform according to claim 1, characterized in that: The concentration of the ascorbic acid is 0.05-1M.

5. The preparation method and application of a MXene-Au nanocomposite multifunctional antibacterial platform according to claim 1, characterized in that: The concentration of HAuCl4 is 0.5-50 mM.

6. The preparation method and application of a MXene-Au nanocomposite multifunctional antibacterial platform according to claim 1, characterized in that: The concentration of the Ti3C2-Au seeds is 0.5-5 mg / mL.

7. The preparation method and application of a MXene-Au nanocomposite multifunctional antibacterial platform according to claims 1 to 6, characterized in that: The Ti3C2-Au nanocomposite material is constructed by combining an electrostatic assembly method with a seed growth method to synthesize a composite material (Ti3C2-Au NWs) with gold nanowire arrays on both sides of a Ti3C2 nanosheet.

8. The preparation method and application of a MXene-Au nanocomposite multifunctional antibacterial platform according to claim 7, characterized in that: The composite material of gold nanowire arrays on both sides of the Ti3C2 nanosheet integrates the functions of capture, detection and killing. The large number of nano tentacles in Ti3C2-AuNWs improve the ability to capture bacteria. By adjusting the wavelength of the irradiated light, the material can undergo photothermal conversion to achieve the purpose of photothermal conversion sterilization. Since Ti3C2-AuNWs has its own MBA molecules, it can be used as an internal standard to provide a stable and effective signal to achieve SERS detection of bacteria.

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