A method for preparing core-shell structured mesoporous nanoparticles and their application in combined near-infrared photothermal and photodynamic antibacterial activity.
By preparing core-shell structured mesoporous nanoparticles MSN/G@mPDA/F and combining photodynamic and photothermal therapy, the shortcomings of existing therapies in the treatment of bacterial infections were overcome, achieving a highly efficient bactericidal effect in hypoxic environments.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- EAST CHINA UNIV OF SCI & TECH
- Filing Date
- 2026-03-11
- Publication Date
- 2026-05-26
AI Technical Summary
Existing photothermal and photodynamic therapies for treating bacterial infections suffer from uneven heat distribution, limited bacterial killing effects due to high expression of heat shock proteins, and high dependence of photodynamic therapy on oxygen concentration, making them difficult to apply effectively in hypoxic infection environments.
Core-shell mesoporous nanoparticles MSN/G@mPDA/F were prepared using emulsion epitaxy. The core was mesoporous silica loaded with S-nitrosoglutathione, and the shell was mesoporous polydopamine loaded with pentafluorophenyl chlorophyll. Combining the advantages of photodynamic therapy and photothermal therapy, nanoparticles with high singlet oxygen generation and photothermal conversion capabilities were formed.
It achieves the synergistic effect of photodynamic therapy and photothermal therapy, improves the bactericidal effect, is suitable for large-scale synthesis, and can effectively kill bacteria in hypoxic environments, with good biocompatibility and stability.
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Abstract
Description
Technical Field
[0001] This invention belongs to the field of biomedical materials and nanotechnology, specifically relating to a method for preparing core-shell structured mesoporous nanoparticles and their application in near-infrared photothermal and photodynamic combined antibacterial processes. Background Technology
[0002] Bacterial infections are one of the leading causes of death in humans, second only to cancer, claiming tens of thousands of lives each year. The advent of antibiotics has largely alleviated the harm caused by bacterial infections; common antibiotics include azithromycin, levofloxacin, and doxycycline, reducing the symptoms of postoperative bacterial infections. However, the widespread use of antibiotics has led to the gradual development of antibiotic resistance in bacteria, with some bacteria even evolving into drug-resistant "superbugs," seriously threatening human health. Therefore, we urgently need a treatment plan and strategy that is free from antibiotics, among which photodynamic therapy and photothermal therapy have received significant attention.
[0003] Photothermal therapy is an emerging minimally invasive and precise antibacterial treatment technology. It utilizes a photothermal converter to generate heat under laser irradiation at a specific wavelength (usually near-infrared light), locally and precisely burning and ablating bacterial colonies. It has the following advantages: precise and minimally invasive, controllable and efficient, synergistic effects, and immune stimulation. Photodynamic therapy is a minimally invasive therapy that uses photosensitizers, specific wavelength light sources, and oxygen to treat diseases (especially cancer). It has the following advantages: precise targeting and minimal invasiveness, low toxicity, high safety, and repeatability. However, both have their shortcomings. Photothermal therapy suffers from uneven heat distribution and limited effectiveness against bacteria expressing high levels of heat shock proteins. Photodynamic therapy is highly dependent on oxygen concentration, while the bacterial microenvironment is an anaerobic environment with a large infection area. Therefore, there is an urgent need to develop a core-shell structure-based mesoporous nanoparticle to combine the two, complementing each other to achieve a synergistic effect greater than the sum of its parts.
[0004] Core-shell mesoporous nanoparticles offer several advantages: extremely high specific surface area and pore volume, enabling efficient loading of large quantities of drugs, catalysts, or genes; tunable and uniform pore size, facilitating molecular sieving and controlled release; ease of functionalization, with flexible surface modification allowing for targeted delivery, intelligent response, and other advanced functions through the grafting of different functional groups; and excellent biocompatibility, being non-toxic and possessing broad application prospects in the biomedical field. Summary of the Invention
[0005] In view of this, the present invention provides a method for preparing and applying core-shell structured mesoporous nanoparticles. The method is characterized by the successful construction of mesoporous nanoparticles with a core-shell structure containing S-nitrosoglutathione, pentafluorophenylchlorophyll, mesoporous silica, and mesoporous polydopamine using an emulsion epitaxial growth method, forming MSN / G@mPDA / F nanoparticles. Furthermore, the core is mesoporous silica loaded with nitric oxide donor, and the outer shell is mesoporous polydopamine loaded with pentafluorophenylchlorophyll. These nanoparticles possess excellent photodynamic and photothermal therapy capabilities, allowing them to complement each other and achieve a synergistic effect greater than the sum of their parts (1+1>2).
[0006] To achieve the above-mentioned technical objectives, the present invention adopts the following technical solution:
[0007] The first aspect of the present invention provides MSN / G@mPDA / F nanoparticles.
[0008] Among them, the core-loaded drug S-nitrosoglutathione is mentioned.
[0009] Among them, the outer shell drug is pentafluorophenyl chlorophyll.
[0010] A second aspect of this invention provides a method for preparing MSN / G@mPDA / F nanoparticles, comprising the following steps:
[0011] S1: Using hydrochloric acid aqueous solution as solvent, glutathione and nitrosamine as reactants, and hydrochloric acid as catalyst, S-nitrosoglutathione is obtained by reaction.
[0012] S2: Using water as a solvent, hexadecyltrimethylammonium chloride as a structure directing agent, triethanolamine as a catalyst, tetraethyl orthosilicate and cyclohexane are stirred and mixed, and then slowly dripped into the water along the bottle wall to form two phases, thus obtaining silica nanoparticles.
[0013] S3 uses the silica nanoparticles from S2 as raw materials and hydrochloric acid and methanol as solvents to obtain mesoporous silica nanoparticles.
[0014] Using mesoporous silica obtained from S3 and dopamine hydrochloride as raw materials, hexadecyltrimethylammonium bromide and F-127 as structure directing agents, water, ethanol, and thiomethylbenzene as solvents, and tris(hydroxymethyl)aminomethane as a catalyst, core-shell structured mesoporous nanoparticles were obtained in S4.
[0015] In S5, the core-shell structured mesoporous nanoparticles obtained in S4 were dispersed evenly with S-nitrosoglutathione and pentafluorophenyl chlorophyll obtained in S1 in an ethanol solution, stirred vigorously for 12 hours, centrifuged, and washed three times with ethanol and distilled water to obtain MSN / G@mPDA / F nanoparticles.
[0016] Preferably, step S1 specifically includes: weighing a certain amount of glutathione and dissolving it in an aqueous hydrochloric acid solution, bathing it on ice for 30 minutes, then preparing an aqueous solution of sodium nitrite and slowly adding it dropwise to the above solution, reacting for 30 minutes, adding ice-cold acetone, and continuing the reaction for 10 minutes. The product is then filtered and washed three times with ice water, ice-cold acetone, and diethyl ether to obtain S-nitrosoglutathione.
[0017] Preferably, step S2 specifically includes: dissolving hexadecyltrimethylammonium chloride and triethanolamine in distilled water at 60 °C. o Stir at 150 r.pm under temperature C until clear. Mix tetraethyl orthosilicate and cyclohexane, sonicate until homogeneous, and slowly drip into the water along the flask wall to form two phases. After reacting for 48 hours, centrifuge and wash three times with distilled water and ethanol to obtain silica nanoparticles.
[0018] Preferably, step S3 specifically includes: adding the silica nanoparticles from S2, along with hydrochloric acid and methanol, into a flask. At 70°C... o Reflux at C for 4 h, repeat this process 3 times, and each time wash with distilled water and ethanol three times and then centrifuge to obtain mesoporous silica nanoparticles.
[0019] Preferably, step S4 specifically includes: dispersing the mesoporous silica obtained in S3 in distilled water and ethanol, then adding hexadecyltrimethylammonium bromide, F-127, and dopamine, and stirring to form a transparent solution. Adding tricresylbenzene and stirring for 30 min forms a milky white emulsion, followed by the addition of tris(hydroxymethyl)aminomethane. The reaction proceeds overnight, then the mixture is centrifuged and washed three times with water and ethanol. Finally, it is sonicated with acetone and ethanol solution and centrifuged three times to obtain core-shell structured mesoporous nanoparticles.
[0020] Preferably, step S5 specifically includes: dispersing the core-shell structured mesoporous nanoparticles obtained in S4 with S-nitrosoglutathione and pentafluorophenyl chlorophyll obtained in S1 in an ethanol solution, stirring vigorously for 12 hours, centrifuging, and washing three times with ethanol and distilled water to obtain MSN / G@mPDA / F nanoparticles.
[0021] A third aspect of the present invention provides an application of MSN / G@mPDA / F nanoparticles in antibacterial applications.
[0022] The MSN / G@mPDA / F nanoparticles provided by this invention have good biocompatibility and stability, high singlet oxygen generation capacity, and good antibacterial effect, and can be used for antibacterial applications.
[0023] The application includes the following tests:
[0024] S1: Mesoporous silica nanoparticles and core-shell structured mesoporous nanoparticles were prepared into an ethanol solution, and their morphology was tested using a transmission electron microscope.
[0025] S2: MSN / G@mPDA / F nanoparticles were prepared into phosphate buffer, wrapped in dialysis bags, placed in plastic tubes, and the extravasation fluid was collected. Drug release and NO release were tested using a UV-Vis spectrophotometer, and the particle size distribution of core-shell mesoporous nanoparticles and mesoporous silica samples was tested using dynamic light scattering.
[0026] S3: The singlet oxygen generation capacity was characterized by blending DPBF solution (a singlet oxygen test reagent) with MSN / G@mPDA / F nanoparticles, irradiating the solution with light, and measuring the UV absorption at 425 nm. The decrease rate of UV absorption was used to characterize the singlet oxygen generation capacity.
[0027] S4: Irradiate MSN / G@mPDA / F nanoparticles with an 808 nm laser and test the photothermal temperature using a precision thermometer probe.
[0028] S5: Using Escherichia coli as the experimental strain, the antibacterial effect of MSN / G@mPDA / F nanoparticles was tested by absorbance method.
[0029] The beneficial effects of this invention are:
[0030] 1. Experiments have shown that the core-shell structured mesoporous nanoparticles of this invention are easy to synthesize, have a stable structure, and are simple to synthesize, making them suitable for large-scale synthesis.
[0031] 2. Experiments have shown that the MSN / G@mPDA / F nanoparticles in this invention have good antibacterial ability.
[0032] 3. Experiments have shown that the MSN / G@mPDA / F nanoparticles in this invention can effectively release drugs.
[0033] 4. Experiments have shown that the MSN / G@mPDA / F nanoparticles in this invention can enable photodynamic therapy and photothermal therapy to work synergistically, and have broad application prospects. Attached Figure Description
[0034] Figure 1 S-nitrosoglutathione 1 H-NMR spectrum;
[0035] Figure 2 Transmission electron microscope image of mesoporous silica;
[0036] Figure 3 Transmission electron microscope image of core-shell mesoporous nanoparticles;
[0037] Figure 4This is a particle size distribution diagram of mesoporous silica nanoparticles;
[0038] Figure 5 This is a particle size distribution diagram of core-shell mesoporous nanoparticles;
[0039] Figure 6 The UV absorption spectrum of NO release from MSN / G@mPDA / F nanoparticles;
[0040] Figure 7 The UV absorption spectrum of dual-drug release from MSN / G@mPDA / F nanoparticles;
[0041] Figure 8 Photothermal temperature diagram of MSN / G@mPDA / F nanoparticles;
[0042] Figure 9 DPBF UV absorption degradation curves of MSN / G@mPDA / F nanoparticles;
[0043] Figure 10 The image shows the antibacterial experimental results (Staphylococcus aureus) of MSN / G@mPDA / F nanoparticles. Specific implementation methods
[0044] The following description, with reference to the accompanying drawings, illustrates preferred embodiments of the present invention, demonstrating its implementability. These embodiments provide a complete overview of the invention for those skilled in the art, making its technical content clearer and easier to understand. To better understand the essence of the invention, specific operational processes are used to illustrate the concept, but this is not intended to limit the invention. Those skilled in the art can make optimizations and improvements based on the basic principles of the invention, without departing from the fundamental ideas, all of which are within the scope of the invention.
[0045] Example 1
[0046] This embodiment 1 provides a method for preparing S-nitrosoglutathione.
[0047] The preparation method of the above-mentioned S-nitrosoglutathione is as follows:
[0048] Dissolve 1.5 g of glutathione in 8 mL of water, add 0.417 mL of hydrochloric acid (37%), and treat with an ice bath for 30 min. Then, dissolve 0.35 g of sodium nitrite in 2 mL of water and slowly add it dropwise to the above solution. After reacting for 30 min, add 10 mL of ice-cold acetone and react for another 10 min to obtain a pink suspension. Filter under reduced pressure and wash three times with ice water, ice-cold acetone, and diethyl ether to obtain the final product.
[0049] Example 2.
[0050] This embodiment 2 provides a method for synthesizing core-shell structured mesoporous nanoparticles.
[0051] The preparation method of the above-mentioned core-shell structured mesoporous nanoparticles is as follows:
[0052] Synthesis of S1 mesoporous silica
[0053] We synthesized MSN using a two-phase method. 6 g CTAC, 100 μL triethanolamine, and 60 mL distilled water were added to a 100 mL flask. The mixture was heated at 60 °C and stirred at 150 r·pm using a 2 cm rotor until clear. 4 mL TEOS and 16 mL cyclohexane were then stirred and sonicated until homogeneous. This mixture was then slowly added dropwise along the flask wall to the water to form a two-phase reaction. After 48 h of reaction, the mixture was centrifuged and washed three times with distilled water and ethanol.
[0054] Synthesis of S2 core-shell structured mesoporous nanoparticles
[0055] The solution was prepared using an emulsion assembly method. Typically, 5 mg of MSN-100, from which CTAB was extracted, was dispersed in 5 mL of H₂O and 5 mL of ethanol. Then, 10 mg of CTAB, 200 mg of F-127, and 150 mg of dopamine were added, and the mixture was stirred to form a clear solution. 1 mL of TMB was added, and the mixture was stirred for 30 min to form a milky white emulsion. Then, 10 mg of tris(hydroxymethyl)aminomethane was added. The reaction was allowed to proceed overnight, followed by centrifugation and washing three times with water and ethanol.
[0056] Example 3
[0057] This embodiment 3 provides a method for preparing MSN / G@mPDA / F nanoparticles, the preparation method of which is as follows:
[0058] S-nitrosoglutathione and pentafluorophenyl chlorophyll from Example 1 were prepared into distilled aqueous solutions and ethanol solutions of a certain concentration, respectively. Core-shell mesoporous nanoparticles were added, mixed and stirred for 12 hours, and then washed with distilled water and ethanol respectively. After centrifugation three times, MSN / G@mPDA / F nanoparticles were obtained.
[0059] Example 4
[0060] Particle size testing of core-shell mesoporous nanoparticles
[0061] 1. Experimental materials: Core-shell structured mesoporous nanoparticles and mesoporous silica nanoparticles from Example 2.
[0062] 2. Experimental method: Dynamic light scattering was used to determine the particle size distribution of supramolecular nanoparticle solutions.
[0063] 3. Experimental Results: Particle size distribution as follows Figure 4 and Figure 5 As shown, the hydrodynamic diameter of mesoporous silica is 167 nm, and the polydispersity index is 0.20. The hydrodynamic diameter of core-shell structured mesoporous nanoparticles is 206 nm, and the polydispersity index is 0.25.
[0064] Example 5
[0065] Dual-drug release UV absorption assay of MSN / G@mPDA / F nanoparticles
[0066] 1. Experimental materials: MSN / G@mPDA / F nanoparticles in Example 3 of this study.
[0067] 2. Experimental method: First, use phosphate buffer to scan the baseline, then take the external solution of MSN / G@mPDA / F nanoparticle dialysis bag, with a wavelength range of 500 nm-600 nm.
[0068] 3. Experimental results: such as Figure 7 As shown, the MSN / G@mPDA / F nanoparticles exhibit a strong absorption peak at 504 nm, which is the UV absorption of pentafluorophenyl chlorophyll, proving that pentafluorophenyl chlorophyll was successfully released. There is a weaker absorption peak at 548 nm, which is the UV absorption peak of S-nitrosoglutathione, indicating that S-nitrosoglutathione was successfully released.
[0069] Example 6
[0070] Photothermal temperature diagram of MSN / G@mPDA / F nanoparticles
[0071] 1. Experimental materials: MSN / G@mPDA / F nanoparticles in Example 3 of this study.
[0072] 2. Experimental method: MSN / G@mPDA / F nanoparticles were dispersed in phosphate buffer, a temperature detector was placed in the buffer, and the temperature was observed by irradiating the particles with 808 nm lasers of different powers.
[0073] 3. Experimental results: such as Figure 8 As shown, the highest temperature of MSN / G@mPDA / F nanoparticles reaches about 55 ℃, and the highest temperature will be reached even faster when the power is high.
[0074] Example 7
[0075] DPBF UV absorption degradation curve of MSN / G@mPDA / F nanoparticles
[0076] 1. Experimental materials: MSN / G@mPDA / F nanoparticles in Example 3 of this study.
[0077] 2. Experimental method: MSN / G@mPDA / F nanoparticles were mixed with singlet oxygen detection reagent DPBF to form a solution. Each group was irradiated with a light source with a wavelength of 650 nm. The ultraviolet absorption of the solution at 425 nm was detected every 10 seconds of irradiation. The experiment was repeated 6 times.
[0078] 3. Experimental results: such as Figure 9 As shown, the absorption peak at 425 nm gradually decreases, indicating the successful generation of singlet oxygen.
[0079] Example 8
[0080] NO release curve of MSN / G@mPDA / F nanoparticles
[0081] 1. Experimental materials: MSN / G@mPDA / F nanoparticles in Example 3 of this study.
[0082] 2. Experimental method: MSN / G@mPDA / F nanoparticles were mixed evenly with Griess reagent and measured using a UV absorption spectrometer.
[0083] 3. Experimental Results: Figure 6 The absorbance at 526 nm gradually increases, indicating that NO was successfully released.
[0084] Example 9
[0085] 1. Experimental materials: MSN / G@mPDA / F nanoparticles in Example 3 of this study.
[0086] 2. Experimental Methods: Bacteria were placed in LB medium at 37 ℃ and shaken overnight. The bacterial culture was then transferred to 96-well plates and cultured with different concentrations of MSN / G@mPDA / F nanoparticles at 37 ℃. At 0.5 h, the plates were irradiated with an 808 nm laser, followed by irradiation with a 750 nm laser. After 24 h, the bacterial OD value at 600 nm was measured using a microplate reader.
[0087] 3. Experimental results: such as Figure 10 As shown, bacterial mortality was determined by calculating the relative percentage of the remaining concentration using the OD value of PBS as 100%. Bacterial activity was well inhibited at a concentration of 4 mg / mL.
[0088] Depend on Figure 6 The results show that the MSN / G@mPDA / F nanoparticles prepared in Example 3 of this invention can release NO. Figure 7 The successful release of the two drugs. Figure 8 , 9 As can be seen from the above, the MSN / G@mPDA / F nanoparticles prepared in Example 3 of this invention have good photothermal capabilities and singlet oxygen generation capabilities. Figure 10 The MSN / G@mPDA / F nanoparticles prepared in Example 3 of this invention have excellent antibacterial properties.
[0089] The above description is only a preferred embodiment of the present invention. It should be noted that other embodiments obtained by those skilled in the art without creative effort should also be considered within the scope of protection of the present invention.
Claims
1. A core-shell structured mesoporous nanoparticle, characterized in that... Mesoporous nanoparticles containing S-nitrosoglutathione, pentafluorophenylchlorophyll, mesoporous silica, and mesoporous polydopamine were successfully constructed using an emulsion epitaxy method based on hydrophilic-hydrophobic interactions. The core is a mesoporous silica-loaded nitric oxide donor, and the outer shell is a mesoporous polydopamine-loaded pentafluorophenylchlorophyll.
2. The method for preparing core-shell structured mesoporous nanoparticles according to claim 1, characterized in that, The process includes the following steps: S1. A certain amount of glutathione is weighed and dissolved in an aqueous hydrochloric acid solution. The solution is treated in an ice bath for 30 minutes. Then, an aqueous solution of sodium nitrite is slowly added dropwise to the above solution. The reaction is allowed to proceed for 30 minutes. Ice acetone is added, and the reaction continues for another 10 minutes. The product is then filtered and washed three times with ice water, ice acetone, and diethyl ether to obtain S-nitrosoglutathione. S2. Cetyltrimethylammonium chloride and triethanolamine are dissolved in distilled water and stirred at 150 r.pm at 60°C until clear. Tetraethyl orthosilicate and cyclohexane are stirred and mixed, sonicated until homogeneous, and then slowly added dropwise along the wall of the flask to the above water to form a two-phase reaction. After reacting for 48 hours, the mixture is centrifuged and washed three times with distilled water and ethanol to obtain silica nanoparticles. S3. The silica nanoparticles from S2 are added to a flask with hydrochloric acid and methanol. The mixture is refluxed at 70°C for 4 hours. This process is repeated three times, with each washing three times with distilled water and ethanol followed by centrifugation to obtain mesoporous silica nanoparticles. S4: The mesoporous silica obtained in S3 was dispersed in distilled water and ethanol, then hexadecyltrimethylammonium bromide, F-127, and dopamine were added, and the mixture was stirred to form a transparent solution. Trimethylbenzene was added, and the mixture was stirred for 30 min to form a milky white emulsion, followed by the addition of tris(hydroxymethyl)aminomethane. The reaction was carried out overnight, then centrifuged, and washed three times with water and ethanol. The mixture was then sonicated with acetone and ethanol solution, and centrifuged three times to finally obtain core-shell structured mesoporous nanoparticles. S5: The core-shell structured mesoporous nanoparticles obtained in S4 were dispersed uniformly with S-nitrosoglutathione and pentafluorophenyl chlorophyll obtained in S1 in an ethanol solution, stirred vigorously for 12 hours, centrifuged, and washed three times with ethanol and distilled water to obtain MSN / G@mPDA / F nanoparticles.
3. The preparation method of MSN / G@mPDA / F according to claim 2, characterized in that, The core-shell structured mesoporous nanoparticles described in step S4.
4. The preparation method of MSN / G@mPDA / F according to claim 2, characterized in that, The nitric oxide donor in step S5 is S-nitrosoglutathione.
5. An application of the MSN / G@mPDA / F as described in claims 1-4, characterized in that... Nanoparticles that combine photodynamic therapy and photothermal therapy for antibacterial applications exhibit good antibacterial capabilities.