A method for preparing porphyrin-based graphyne analog-modified titanium carbide nanosheets and its application in the field of antibacterial agents.

Abstract

A method for preparing porphyrin-based graphyne analog-modified titanium carbide nanosheets and its application in the antibacterial field belongs to the field of functional nanomaterial preparation. First, titanium carbide is prepared by selectively etching an aluminum layer from aluminum-carbon titanium. Then, 4-trimethylsilynylbenzaldehyde and pyrrole are used as raw materials to undergo a condensation reaction to obtain TTPP. Next, anhydrous zinc acetate is used for metal coordination, and tetrabutylammonium fluoride is used for TMS deprotection to obtain Zn-TEPP. Finally, Zn-TEPP and titanium carbide are prepared by a Glaser-Hay coupling reaction, which does not destroy the surface structure of titanium carbide, maintains the original morphology and structure of the titanium carbide nanosheets, and has a large specific surface area. The photodynamic properties of PDY combined with the photothermal properties of MXene can further enhance the bactericidal performance of the composite material. In addition, PDY-modified MXene is more stable in air and water, thereby further improving the bactericidal stability of MXene.

Description

Technical Field

[0001] This invention belongs to the field of functional nanomaterial preparation, specifically relating to a method for preparing porphyrin-based graphyne analog-modified titanium carbide nanosheets and their application in the field of antibacterial agents. Background Technology

[0002] Bacterial infections are a leading cause of death from disease worldwide, with numerous cases globally. They currently cause high morbidity and mortality rates, posing significant challenges to biomedicine and becoming one of the most serious problems recognized globally. Since the discovery and use of penicillin as an antibiotic, the problem of bacterial infections has been effectively alleviated. However, the overuse of antibiotics has led to the emergence of drug-resistant bacteria, gradually reducing the effectiveness of traditional antibiotics in treating bacterial infections. In particular, "superbugs" exhibit significant antibacterial activity against almost all antibiotics, posing a major threat to the treatment of bacterial infections. Therefore, the development of novel antibacterial materials is of great importance.

[0003] In recent years, advancements in nanotechnology have driven the exploration of innovative nanoplatforms for treating serious diseases. Among these, photodynamic therapy (PDT) and photothermal therapy (PTT) have received significant attention. PDT utilizes light irradiation to activate a photothermal agent, converting the absorbed light into heat, thereby killing bacteria by disrupting cell membrane structures and denaturing proteins. PDT does not induce drug-resistant bacteria, thus exhibiting good bactericidal effects against superbugs. PDT uses light of a specific wavelength to excite a photosensitizer, which transfers energy to surrounding oxygen, generating highly reactive singlet oxygen. This singlet oxygen further reacts with nearby biomolecules, producing cytotoxicity and killing pathogenic microorganisms. PDT is considered an effective novel antibacterial strategy due to its non-invasive nature, fewer side effects, and lack of drug-resistant bacteria. Chinese patent CN 118217395 A reports a selenium-doped gold-silver bimetallic nanoparticle exhibiting a rapid photothermal heating response under near-infrared light irradiation. Chinese patent CN114209826 B reports the preparation and application of zinc porphyrin nanoparticles, which can effectively generate singlet oxygen and convert photons into heat energy under specific wavelength light irradiation, giving the particles excellent drug loading capacity and enabling combined PDT and PTT treatment.

[0004] This invention attempts to prepare two-dimensional MXene nanosheets modified with porphyrin-based graphyne analogues (PDY-MXene) and apply them to photothermal / photodynamic synergistic antibacterial therapy, hoping to exert their excellent bactericidal properties. Summary of the Invention

[0005] The technical problem to be solved by the present invention is to overcome the shortcomings of the prior art and provide a method for preparing porphyrin-based graphyne analog-modified titanium carbide nanosheets and their application in the field of antibacterial.

[0006] To achieve the above objectives, the technical solution adopted by the present invention is as follows:

[0007] A method for preparing porphyrin-based graphyne analog-modified titanium carbide nanosheets involves first selectively etching an aluminum layer from carbon-aluminum-titanium to obtain titanium carbide. Then, 4-trimethylsilynylbenzaldehyde and pyrrole are used as raw materials to undergo a condensation reaction to obtain 5,10,15,20-tetra(4-ethynylphenyl)porphyrin (TTPP). Next, anhydrous zinc acetate is used for metal coordination, and tetrabutylammonium fluoride is used for TMS deprotection to obtain Zn(II)5,10,15,20-tetra(4-ethylphenyl)porphyrin (Zn-TEPP). Finally, Zn-TEPP and titanium carbide are coupled via a Glaser-Hay coupling reaction to obtain porphyrin-based graphyne analog-modified titanium carbide (PDY-MXene) nanosheets.

[0008] Furthermore, the preparation steps of porphyrin-based graphyne analog-modified titanium carbide nanosheets are as follows:

[0009] 1) First, titanium carbide precipitate is prepared by etching the aluminum atom layer in titanium carbide with a mixed solution of hydrochloric acid and lithium fluoride. Then, the titanium carbide precipitate is dispersed in water by ultrasonication, the precipitate is removed by centrifugation, the supernatant is taken and dried to obtain titanium carbide nanosheets.

[0010] 2) Using 4-trimethylsilynylbenzaldehyde and pyrrole as raw materials, a condensation reaction was carried out to obtain 5,10,15,20-tetra(4-ethynylphenyl)porphyrin (TTPP) powder;

[0011] 3) Zn(II)5,10,15,20-tetra(4-ethynylphenyl)porphyrin (Zn-TTPP) powder was obtained by metal coordination of TTPP and anhydrous zinc acetate;

[0012] 4) Zn(II)5,10,15,20-tetra(4-ethylphenyl)porphyrin (Zn-TEPP) powder was obtained by removing TMS protection from Zn-TTPP with tetrabutylammonium fluoride;

[0013] 5) According to the mass ratio of Zn-TEPP to titanium carbide of 1:2-4, add the Zn-TEPP powder obtained in step 4) and the titanium carbide nanosheets obtained in step 1) into N,N-dimethylformamide solution. The nanoparticle precipitate obtained after the reaction is porphyrin-based graphyne analog modified titanium carbide (PDY-MXene) nanosheets.

[0014] As a further preferred technical solution of the present invention, the specific steps of step 1) in the preparation method for preparing titanium carbide nanosheets are as follows: First, take 500 mg of aluminum titanium carbon, 500 mg of lithium fluoride, 2.5 mL of deionized water and 7.5 mL of hydrochloric acid, mix them thoroughly, and put them into an oil bath at 41°C and stir for 48-72 h. After the reaction is completed, add deionized water and wash with a centrifuge until pH=7. Take the precipitate and add it to 100-120 mL of deionized water, sonicate at 0-25°C for 40-60 min, then centrifuge, take the supernatant, and freeze-dry to obtain titanium carbide nanosheets.

[0015] As a further preferred technical solution of the present invention, the specific steps of step 2) in the preparation method for preparing 5,10,15,20-tetra(4-ethynylphenyl)porphyrin (TTPP) powder are as follows: Take 15g 4-Trimethylsilynylbenzaldehyde, 30-50 mL of propionic anhydride, and 200-250 mL of propionic acid were added to a three-necked flask, stirred, and nitrogen gas was introduced for 15 min. A mixture of 50-75 mL of propionic anhydride and 10.5-12 mL of pyrrole was slowly added dropwise to a constant-temperature oil bath at 100-120 °C. Nitrogen gas was continuously introduced for 15 min, and the reaction was stirred for 3 h. The mixture was then cooled to room temperature. The solvent was removed by vacuum filtration to obtain a crude purplish-black porphyrin product. The crude product was purified by column chromatography (using dichloromethane: petroleum ether = 1:2 as the eluent), and the solvent was completely removed under reduced pressure. The product was dried in a vacuum drying oven at 60 °C to obtain 5,10,15,20-tetra(4-ethynylphenyl)porphyrin (TTPP) powder.

[0016] As a further preferred technical solution of the present invention, the specific steps of step 3) in the preparation method for preparing Zn(II)5,10,15,20-tetra(4-ethynylphenyl)porphyrin (Zn-TTPP) powder are as follows: 900 mg TTPP and 2.8 g anhydrous zinc acetate are added to N,N-dimethylformamide, stirred at 80-100 °C for 10-14 h under a nitrogen atmosphere, cooled to room temperature, and the solvent is completely removed under reduced pressure. The powder is washed with deionized water and methanol, and dried in a vacuum drying oven at 60 °C to obtain Zn(II)5,10,15,20-tetra(4-ethynylphenyl)porphyrin (Zn-TTPP) powder.

[0017] As a further preferred technical solution of the present invention, the specific steps of step 4) in the preparation method for preparing Zn(II)5,10,15,20-tetra(4-ethylphenyl)porphyrin (Zn-TEPP) powder are as follows: under a nitrogen atmosphere, 400 mg of Zn-TTPP is dissolved in 40 mL of tetrahydrofuran, and then 2.4 mL of a TBAF / THF mixed solution is added. The mixture is stirred at room temperature for 12-24 h, then extracted with dichloromethane and water, dried with anhydrous sodium sulfate, and finally filtered under vacuum to obtain the solvent. The solvent is then removed under reduced pressure and dried in a vacuum drying oven to obtain Zn(II)5,10,15,20-tetra(4-ethylphenyl)porphyrin (Zn-TEPP) powder.

[0018] As a further preferred technical solution of the present invention, in step 5) of the preparation method, 25 mg of Zn(II)5,10,15,20-tetra(4-ethylphenyl)porphyrin (Zn-TEPP) powder obtained in step 4) and 50-100 mg of titanium carbide nanosheets obtained in step 1) are added to an N,N-dimethylformamide solution, and cuprous chloride is added. The mixture is stirred and reacted at 60°C for 24-48 h. After the reaction is completed, the product is obtained by washing with N,N-dimethylformamide and methanol, vacuum filtering, and then freeze-drying. The product is porphyrin-based graphyne analog modified titanium carbide (PDY-MXene) nanosheets.

[0019] This invention first prepares a two-dimensional titanium carbide (MXene) through a reasonable preparation process. As a photothermal agent, it exhibits high photothermal conversion efficiency and good bactericidal effect even at relatively low concentrations. When the concentration of two-dimensional titanium carbide (MXene) is 60 μg·mL... -1 It can be achieved in NIR (808nm, 2W·cm) -2 When exposed to light for 6 minutes, the temperature is raised, and bacteria can be inactivated in a short time, with a sterilization rate of over 99%. However, titanium carbide is easily oxidized in air and water, which drastically reduces its antibacterial properties. This invention utilizes porphyrin-based graphyne analogs to modify the interface of titanium carbide (MXene), resulting in PDY-MXene nanosheets with antibacterial properties comparable to titanium carbide, but with greater stability in air and water, thus significantly increasing the antibacterial stability of MXene.

[0020] Compared with the prior art, the superior effects of the present invention are as follows:

[0021] 1) The porphyrin-based graphdiyne analog-modified titanium carbide nanosheets prepared in this invention are formed by the Glaser-Hay coupling reaction of Zn-TEPP and titanium carbide. This process does not damage the surface structure of titanium carbide, maintains the original morphology and structure of the titanium carbide nanosheets, and has a large specific surface area.

[0022] 2) The porphyrin-based graphdiyne analog-modified titanium carbide nanosheets prepared by this invention have good biocompatibility, and the near-infrared light used has spatial controllability and strong penetration ability, and causes very little damage to the human body.

[0023] 3) The porphyrin-based graphyne analog-modified titanium carbide nanosheets prepared in this invention can generate singlet oxygen to further kill bacteria on the basis of photothermal destruction of cell structure, and are more stable in air and water, thereby improving their antibacterial stability. Attached Figure Description

[0024] Figure 1 The 5,10,15,20-tetrakis(4-ethynylphenyl)porphyrin (TTPP) prepared in Example 1 1 1H NMR spectrum (a) and Zn(II)5,10,15,20-tetra(4-ethylphenyl)porphyrin (Zn-TEPP) 1 H NMR spectrum (b).

[0025] Figure 2 Transmission electron microscopy (Cd) images of titanium carbide nanosheets (MXene) (ab) and porphyrin-based graphyne analog-modified titanium carbide (PDY-MXene) prepared in Example 1.

[0026] Figure 3 X-ray diffraction (XRD) patterns of the exfoliated titanium carbide nanosheets (MXene) and porphyrin-based graphdiyne analog-modified titanium carbide (PDY-MXene) prepared in Example 1.

[0027] Figure 4 X-ray photoelectron spectra (XPS) of the exfoliated titanium carbide nanosheets (MXene), porphyrin-based graphyne analog-modified titanium carbide (PDY-MXene), and porphyrin-based graphyne analog (PDY) prepared in Example 1.

[0028] Figure 5 Raman spectra of the exfoliated titanium carbide nanosheets (MXene), porphyrin-based graphyne analog-modified titanium carbide (PDY-MXene), and porphyrin-based graphyne analog (PDY) prepared in Example 1.

[0029] Figure 6 The image shows infrared photothermal imaging and time-temperature changes of the porphyrin-based graphynyne analog-modified titanium carbide nanosheets (PDY-MXene) prepared in Example 1 dispersed in an aqueous solution.

[0030] Figure 7Images of the bactericidal effects of exfoliated titanium carbide nanosheets (MXene) and porphyrin-based graphyne analog-modified titanium carbide (PDY-MXene) prepared in Example 1 using plate counting method (a: Staphylococcus aureus; b: Escherichia coli).

[0031] Figure 8 Images of the bactericidal effects of the exfoliated titanium carbide nanosheets (MXene) and porphyrin-based graphdiyne analog-modified titanium carbide (PDY-MXene) prepared in Example 1 after soaking in water for seven days using plate count method (a: Staphylococcus aureus; b: Escherichia coli) and counts (c: Staphylococcus aureus; d: Escherichia coli). Detailed Implementation

[0032] The following description, in conjunction with embodiments and accompanying drawings, provides a more detailed explanation of the preparation method of porphyrin-based graphyne analog-modified graphyne nanosheets of the present invention and their application in the field of antibacterial applications.

[0033] Example 1

[0034] Preparation of porphyrin-based graphyne analogue-modified graphyne (PDY-MXene) nanosheets:

[0035] 1) Take 500 mg of titanium aluminum carbon, 500 mg of lithium fluoride, 2.5 mL of deionized water and 7.5 mL of hydrochloric acid, mix them thoroughly and place them in an oil bath at 41 °C with stirring for 48 h. After the reaction is complete, add deionized water, centrifuge at 9500 r / min for 5 min and wash until the supernatant reaches pH = 7. Take the precipitate and add it to 100 mL of deionized water, sonicate at 0 °C for 40 min, then centrifuge at 4000 r / min for 5 min, take the supernatant and freeze-dry to obtain titanium carbide nanosheets.

[0036] 2) Add 15g of 4-trimethylsilynylbenzaldehyde, 50mL of propionic anhydride, and 250mL of propionic acid to a three-necked flask, stir, and purge with nitrogen for 15min. Slowly add a mixture of 75mL of propionic anhydride and 10.5mL of pyrrole dropwise to a constant-temperature oil bath, setting the reaction temperature to 100℃. Continue purging with nitrogen for 15min, stir for 3h, and then cool to room temperature. Remove the solvent by vacuum filtration to obtain a crude purplish-black porphyrin product. Purify the crude product by column chromatography (using dichloromethane:petroleum ether = 1:2 as eluent), completely remove the solvent under reduced pressure, and dry in a vacuum drying oven at 60℃ to obtain 5,10,15,20-tetrakis(4-ethynylphenyl)porphyrin (TTPP) powder.

[0037] 3) Take 900 mg of TTPP and 2.8 g of anhydrous zinc acetate obtained in step 2) and add them to N,N-dimethylformamide. Stir at 80 °C for 10 h under a nitrogen atmosphere, cool to room temperature, and completely remove the solvent under reduced pressure. Wash the powder with deionized water and methanol, and dry it in a vacuum drying oven at 60 °C to obtain Zn(II)5,10,15,20-tetra(4-ethynylphenyl)porphyrin (Zn-TTPP) powder.

[0038] 4) Dissolve 400 mg of Zn-TTPP obtained in step 3) in 40 mL of tetrahydrofuran. Under a nitrogen atmosphere, add 2.4 mL of a TBAF / THF mixed solution and stir at room temperature for 12 h. Then extract with dichloromethane and water, dry with anhydrous sodium sulfate, filter under vacuum to obtain the solvent, remove the solvent under reduced pressure, and dry in a vacuum drying oven to obtain Zn(II)5,10,15,20-tetra(4-ethylphenyl)porphyrin (Zn-TEPP) powder.

[0039] 5) Take 25 mg of Zn(II)5,10,15,20-tetra(4-ethylphenyl)porphyrin (Zn-TEPP) powder obtained in step 4) and 100 mg of titanium carbide nanosheets obtained in step 1) and add them to N,N-dimethylformamide solution, and add 8 mg of cuprous chloride. Stir the reaction at 60 °C for 24 h. After the reaction is completed, wash with N,N-dimethylformamide and methanol, filter under vacuum and freeze dry to obtain the product, which is porphyrin-based graphyne analog modified titanium carbide (PDY-MXene) nanosheets.

[0040] In contrast, porphyrin-based graphyne analogues (PDY) were prepared using the following method:

[0041] Under a nitrogen atmosphere, copper foil (3cm×1cm) (which was ultrasonically treated in 2mol / L hydrochloric acid, ethanol and acetone in sequence to remove surface impurities) was added to 50mL of pyridine and heated to 70℃. Then, Zn-TEPP (40mg) from step 4) was dissolved in 20mL of acetone and added through a syringe. The reaction was carried out for 48h and cooled to room temperature. The copper foil was then washed with DMF and methanol in sequence and vacuum dried to obtain porphyrin-based graphyne analogue (PDY).

[0042] Figure 1 The 5,10,15,20-tetrakis(4-ethynylphenyl)porphyrin (TTPP) prepared in Example 1 1 1H NMR spectrum (a) and Zn(II)5,10,15,20-tetra(4-ethylphenyl)porphyrin (Zn-TEPP) 1¹H NMR spectrum (b). The singlet at chemical shift 8.82 corresponds to a hydrogen atom on the porphyrin ring. The doublets at chemical shifts 8.15 and 7.88 correspond to hydrogen atoms on the benzene ring. The singlet at chemical shift 0.38 corresponds to a methyl hydrogen atom. The singlet at chemical shift -2.85 corresponds to an amino hydrogen atom on the porphyrin ring. This indicates that TTPP and Zn-TTPP were successfully prepared.

[0043] Figure 2 Transmission electron microscopy (TEM) images (cd) of titanium carbide nanosheets (MXene) (ab) and porphyrin-based graphyne analog-modified titanium carbide (PDY-MXene) prepared in Example 1. Figure 2 As can be seen from (ab), MXene has a two-dimensional sheet structure with a large surface area and a smooth surface. Figure 2 c shows the lattice fringes of MXene and PDY, with corresponding lattice spacing and interlayer spacing of MXene (0.256 nm) and PDY (0.356 nm), respectively. Figure 2 d). The successful synthesis of PDY-MXene nanocomposites was confirmed.

[0044] Figure 3 X-ray diffraction (XRD) patterns of the exfoliated titanium carbide nanosheets (MXene) and porphyrin-based graphyne analog-modified titanium carbide (PDY-MXene) prepared in Example 1. Figure 3 As can be seen, pure MXene nanosheets exhibit a distinct diffraction peak at 6.38°. Corresponding to the (002) crystal plane of MXene, according to Bragg's formula 2dsinθ=nλ, the interlayer spacing on the (002) crystal plane is 1.39 nm. The diffraction peak of the (002) crystal plane of PDY-MXene shifts to the left to 6.02° compared to pure MXene, with an interlayer spacing of 1.47 nm, indicating that the incorporation of PDY leads to an increase in the lattice spacing of PDY-MXene.

[0045] Figure 4 X-ray photoelectron spectroscopy (XPS) spectra of the exfoliated titanium carbide nanosheets (MXene), porphyrin-based graphyne analog-modified titanium carbide (PDY-MXene), and porphyrin-based graphyne analog (PDY) prepared in Example 1. Figure 4 As can be seen from the data, compared with MXene nanosheets, PDY-MXene has additional N1s and Zn2p peaks on its surface. N and Zn are unique elements of PDY-MXene, indicating that PDY-MXene was successfully prepared.

[0046] Figure 5Raman spectra of the exfoliated titanium carbide nanosheets (MXene), porphyrin-based graphyne analog-modified titanium carbide (PDY-MXene), and porphyrin-based graphyne analog (PDY) prepared in Example 1. Figure 5 It can be clearly seen that PDY and PDY-MXene are at 999, 1058, 1237 and 1347 cm⁻¹ -1 The peaks at [value] originate from the vibrations of phenyl, CH, C-ph, and CN, respectively. Meanwhile, at 1489 cm⁻¹... -1 and 1546cm -1 Both peaks at 2196 cm⁻¹ originate from the vibration of carbon-carbon double bonds. In particular, the peak at 2196 cm⁻¹... -1 The characteristic peak at this location originates from the vibration of the -C≡CC≡C- (conjugated diacetylene bond). Furthermore, the Raman spectrum of pure MXene shows a peak in the 900-2300 cm⁻¹ range. -1 No obvious peaks were observed within the specified range, indicating that PDY-MXene was successfully prepared.

[0047] Figure 6 This is an infrared photothermal imaging and time-temperature variation data graph of the porphyrin-based graphdiyne analog-modified titanium carbide nanosheets (PDY-MXene) prepared in Example 1 dispersed in an aqueous solution. Figure 6 As can be seen, PDY-MXene has significant photothermal properties.

[0048] Example 2

[0049] Preparation of porphyrin-based graphyne analogue-modified graphyne (PDY-MXene) nanosheets:

[0050] 1) Take 500 mg of titanium aluminum carbon, 500 mg of lithium fluoride, 2.5 mL of deionized water and 7.5 mL of hydrochloric acid, mix them thoroughly, and place them in an oil bath at 41 °C with stirring for 60 h. After the reaction is complete, add deionized water, centrifuge at 9500 r / min for 5 min and wash until the supernatant reaches pH 7. Take the precipitate and add it to 120 mL of deionized water, sonicate at 10 °C for 60 min, then centrifuge at 4000 r / min for 5 min, take the supernatant and freeze-dry to obtain titanium carbide nanosheets.

[0051] 2) Add 15g of 4-trimethylsilynylbenzaldehyde, 30mL of propionic anhydride, and 200mL of propionic acid to a three-necked flask, stir, and purge with nitrogen for 15min. Slowly add a mixture of 50mL of propionic anhydride and 12mL of pyrrole in a constant-temperature oil bath, setting the reaction temperature to 120℃. Continue purging with nitrogen for 15min, stir, and react for 3h, then cool to room temperature. Remove the solvent by vacuum filtration to obtain a crude purplish-black porphyrin product. The crude product is subjected to column chromatography (dichloromethane:petroleum ether = 1:2 as eluent), and the solvent is completely removed under reduced pressure. Dry in a vacuum drying oven at 60℃ to obtain 5,10,15,20-tetrakis(4-ethynylphenyl)porphyrin (TTPP) powder.

[0052] 3) Take 900 mg of TTPP and 2.8 g of anhydrous zinc acetate obtained in step 2) and add them to N,N-dimethylformamide. Stir at 100 °C for 14 h under a nitrogen atmosphere, cool to room temperature, and completely remove the solvent under reduced pressure. Wash the powder with deionized water and methanol, and dry it in a vacuum drying oven at 60 °C to obtain Zn(II)5,10,15,20-tetra(4-ethynylphenyl)porphyrin (Zn-TTPP) powder.

[0053] 4) Dissolve 400 mg of Zn-TTPP obtained in step 3) in 40 mL of tetrahydrofuran. Under a nitrogen atmosphere, add 2.4 mL of a TBAF / THF mixed solution and stir at room temperature for 24 h. Then extract with dichloromethane and water, dry with anhydrous sodium sulfate, and finally filter under vacuum to obtain the solvent. Remove the solvent under reduced pressure and dry in a vacuum drying oven to obtain Zn(II)5,10,15,20-tetra(4-ethylphenyl)porphyrin (Zn-TEPP) powder.

[0054] 5) Take 25 mg of Zn(II)5,10,15,20-tetra(4-ethylphenyl)porphyrin (Zn-TEPP) powder obtained in step 4) and 50 mg of titanium carbide nanosheets obtained in step 1) and add them to N,N-dimethylformamide solution, and add 8 mg of cuprous chloride. Stir and react at 60 °C for 28 h. After the reaction is completed, wash with N,N-dimethylformamide and methanol, filter under vacuum and freeze dry to obtain the product, which is porphyrin-based graphyne analog modified titanium carbide (PDY-MXene) nanosheets.

[0055] Example 3

[0056] Antibacterial activity test of porphyrin-based graphyne analog-modified graphyne (PDY-MXene) nanosheets:

[0057] The exfoliated titanium carbide nanosheets (MXene) and porphyrin-based graphyne analog-modified titanium carbide (PDY-MXene) prepared in Example 1 were dispersed in broth used for bacterial culture at concentrations of 0, 30, 60, and 90 μg·mL, respectively. -1 At 2W·cm -2 Irradiation with an 808 nm laser for 6 min, followed by incubation at 37 °C for 4 h, followed by dilution with phosphate buffer (10000-fold), and 100 μL of the diluted suspension was plated onto Luria Bertani agar medium and incubated at 37 °C for 16 h to obtain colony images. The exfoliated titanium carbide nanosheets (MXene) and porphyrin-based graphyne analog-modified titanium carbide (PDY-MXene) were then immersed in water for 7 days before antibacterial experiments were conducted. Colony images were obtained after treatment, and bacterial counts were performed to calculate the bactericidal rate. Results are as follows: Figure 7 , 8 And as shown in Table 1.

[0058] The bactericidal effects of exfoliated titanium carbide nanosheets (MXene) and porphyrin-based graphyne analog-modified titanium carbide (PDY-MXene) prepared in Example 1, as shown in the plate count image. Figure 7 As shown in the figure. The results indicate that the antibacterial properties of both MXene and PDY-MXene increase with increasing concentration, and the effect is most pronounced at a concentration of 60 μg·mL⁻¹. -1 At the same time, the antibacterial properties of the two nanomaterials were comparable, both showing a near 100% bactericidal rate against Escherichia coli and a bactericidal rate of over 99% against Staphylococcus aureus.

[0059] The two materials were soaked in water in the air for 7 days, and then their antibacterial properties were tested. Figure 8 As shown, the results indicate that at a concentration of 60 μg·mL -1 At that time, the photothermal antibacterial properties of MXene decreased significantly, while the bactericidal effect of PDY-MXene was almost unchanged from before soaking in water. As can be seen from the bacterial survival rate in Table 1, PDY-MXene nanosheets treated with 7 days of soaking in water after exposure to air showed a significantly stronger antibacterial effect compared to MXene nanosheets. Furthermore, at a concentration of 60 μg·mL⁻¹... -1 After continuous irradiation for 6 minutes, the bacterial inactivation rate reached approximately 100%. Comparison of the two bacterial strains revealed that photothermal sterilization was more effective against Escherichia coli than against Staphylococcus aureus, due to the difference in cell wall composition between Gram-negative and Gram-positive bacteria.

[0060] Table 1

[0061]

[0062] Table 1 shows the concentrations of Escherichia coli and Staphylococcus aureus at different concentrations (0, 60 μg·mL). -1 MXene (M) and PDY-MXene (PM) (both MXene and PDY-MXene were immersed in water for 7 days), with or without NIR irradiation (808 nm, 2 W·cm⁻¹). -2 The bacterial survival rate of different treatment groups was determined by plate counting method (6 min). In Table 1, L(-) and L(+) represent no light and light, respectively.

[0063] The above description is merely an example and illustration of the concept of the present invention. Those skilled in the art can make various modifications or additions to the specific embodiments described or use similar methods to replace them, as long as they do not deviate from the concept of the invention or exceed the scope defined in the claims, they should all fall within the protection scope of the present invention.

Claims

1. A method for preparing porphyrin-based graphyne analog-modified titanium carbide nanosheets, characterized in that, First, titanium carbide was prepared by selectively etching an aluminum layer from titanium carbide. Then, 5,10,15,20-tetra(4-ethynylphenyl)porphyrin (TTPP) was obtained by condensation reaction of 4-trimethylsilynylbenzaldehyde and pyrrole. Next, anhydrous zinc acetate was used for metal coordination and tetrabutylammonium fluoride was used for deTMS protection to obtain Zn(II)5,10,15,20-tetra(4-ethylphenyl)porphyrin (Zn-TEPP). Finally, Zn-TEPP and titanium carbide were coupled via Glaser-Hay coupling reaction to obtain porphyrin-based graphyne analog-modified titanium carbide (PDY-MXene) nanosheets.

2. The preparation method according to claim 1, characterized in that, The steps are as follows: 1) First, titanium carbide precipitate is prepared by etching the aluminum atom layer in titanium carbide with a mixed solution of hydrochloric acid and lithium fluoride. Then, the titanium carbide precipitate is dispersed in water by ultrasonication, the precipitate is removed by centrifugation, the supernatant is taken and dried to obtain titanium carbide nanosheets. 2) Using 4-trimethylsilynylbenzaldehyde and pyrrole as raw materials, a condensation reaction was carried out to obtain 5,10,15,20-tetra(4-ethynylphenyl)porphyrin (TTPP) powder; 3) Zn(II)5,10,15,20-tetra(4-ethynylphenyl)porphyrin (Zn-TTPP) powder was obtained by metal coordination of TTPP and anhydrous zinc acetate; 4) Zn(II)5,10,15,20-tetra(4-ethylphenyl)porphyrin (Zn-TEPP) powder was obtained by removing TMS protection from Zn-TTPP with tetrabutylammonium fluoride; 5) According to the mass ratio of Zn-TEPP to titanium carbide of 1:2-4, add the Zn-TEPP powder obtained in step 4) and the titanium carbide nanosheets obtained in step 1) into N,N-dimethylformamide solution. The nanoparticle precipitate obtained after the reaction is porphyrin-based graphyne analog modified titanium carbide (PDY-MXene) nanosheets.

3. The preparation method according to claim 2, characterized in that, Step 1) The specific steps for preparing titanium carbide nanosheets are as follows: First, take 500 mg of aluminum titanium carbon, 500 mg of lithium fluoride, 2.5 mL of deionized water and 7.5 mL of hydrochloric acid, mix them thoroughly and put them into an oil bath at 41 °C and stir for 48-72 h. After the reaction is completed, add deionized water and wash with a centrifuge until pH=7. Take the precipitate and add it to 100-120 mL of deionized water. Sonicate at 0-25 °C for 40-60 min, then centrifuge, take the supernatant, and freeze-dry to obtain titanium carbide nanosheets.

4. The preparation method according to claim 3, characterized in that, Step 2) The specific steps for preparing 5,10,15,20-tetra(4-ethynylphenyl)porphyrin (TTPP) powder are as follows: 15g of 4-trimethylsilynylbenzaldehyde, 30-50mL of propionic anhydride and 200-250mL of propionic acid are added to a three-necked flask, stirred and nitrogen gas is introduced for 15min; 50-75mL of a mixture of propionic anhydride and 10.5-12mL of pyrrole is slowly added dropwise to a constant-temperature oil pan, the reaction temperature is set to 100-120℃; nitrogen gas is continuously introduced for 15min, and the reaction is stirred for 3h, then cooled to room temperature; the solvent is removed by vacuum filtration to obtain a crude purplish-black porphyrin product; the crude product is purified by column chromatography, and the solvent is completely removed under reduced pressure, and dried in a vacuum drying oven at 60℃ to obtain 5,10,15,20-tetra(4-ethynylphenyl)porphyrin (TTPP) powder.

5. The preparation method according to claim 4, characterized in that, Step 3) The specific steps for preparing Zn(II)5,10,15,20-tetra(4-ethynylphenyl)porphyrin (Zn-TTPP) powder are as follows: 900 mg of TTPP and 2.8 g of anhydrous zinc acetate are added to N,N-dimethylformamide, stirred at 80-100 °C for 10-14 h under a nitrogen atmosphere, cooled to room temperature, and the solvent is completely removed under reduced pressure. The powder is washed with deionized water and methanol, and dried in a vacuum drying oven at 60 °C to obtain Zn(II)5,10,15,20-tetra(4-ethynylphenyl)porphyrin (Zn-TTPP) powder.

6. The preparation method according to claim 5, characterized in that, Step 4) The specific steps for preparing Zn(II)5,10,15,20-tetra(4-ethylphenyl)porphyrin (Zn-TEPP) powder are as follows: Under a nitrogen atmosphere, 400 mg of Zn-TTPP is dissolved in 40 mL of tetrahydrofuran, and then 2.4 mL of a TBAF / THF mixed solution is added. The mixture is stirred at room temperature for 12-24 h, then extracted with dichloromethane and water, dried with anhydrous sodium sulfate, and finally filtered under vacuum to obtain the solvent. The solvent is then removed under reduced pressure and dried in a vacuum drying oven to obtain Zn(II)5,10,15,20-tetra(4-ethylphenyl)porphyrin (Zn-TEPP) powder.

7. The preparation method according to claim 6, characterized in that, In step 5), 25 mg of Zn(II)5,10,15,20-tetra(4-ethylphenyl)porphyrin (Zn-TEPP) powder obtained in step 4) and 50-100 mg of titanium carbide nanosheets obtained in step 1) are added to an N,N-dimethylformamide solution, and cuprous chloride is added. The mixture is stirred at 60°C for 24-48 h. After the reaction is completed, the mixture is washed with N,N-dimethylformamide and methanol, vacuum filtered, and then freeze-dried to obtain the product, which is porphyrin-based graphyne analog modified titanium carbide (PDY-MXene) nanosheets.

8. The application of porphyrin-based graphyne analog-modified titanium carbide nanosheets prepared by the method according to any one of claims 1-7 in the field of antibacterial agents, characterized in that, It is used as a photosensitizer or photothermal agent in sterilization.

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