A photosensitive compound based on a triphenylamine derivative, its preparation method and application

Abstract

This invention belongs to the field of photodynamic antibacterial materials technology, specifically relating to a photosensitive compound based on a triphenylamine derivative, its preparation method, and its application. The photosensitive compound based on the triphenylamine derivative of this invention is compound I or compound II; the structural formula of compound I is: [structural formula would be inserted here]; the structural formula of compound II is: [structural formula would be inserted here]. The photosensitive compound based on the triphenylamine derivative of this invention exhibits good antibacterial effects, achieving the killing of Staphylococcus aureus and Listeria monocytogenes at significantly lower concentrations (below 0.5 μM; even below 0.25 μM) under white light irradiation.

Description

Technical Field

[0001] This invention belongs to the field of photodynamic antibacterial materials technology, specifically relating to a photosensitive compound based on a triphenylamine derivative, its preparation method, and its application. Background Technology

[0002] With the increasing demands for microbial control in public health, food safety, and healthcare, the development of antimicrobial materials has become a crucial research direction in materials science, biomedicine, and food engineering. Bacterial infections and the resulting food spoilage, biocontamination, and cross-infection not only seriously threaten human health but also cause enormous economic losses. Especially against the backdrop of long-term and extensive use of antibiotics, multidrug-resistant strains are constantly emerging, posing a severe challenge to the effectiveness and sustainability of traditional antimicrobial methods. Therefore, developing novel antimicrobial strategies with high efficiency, low drug resistance risk, and good biosafety is of significant scientific and practical value for reducing infection risks, extending food shelf life, and promoting the development of green and safe antimicrobial technologies.

[0003] Currently, antibacterial agents exist in various forms in packaging materials or protective coatings, mainly including antibiotics, plant essential oils, and metal-based nanomaterials (such as silver and copper nanoparticles). However, the limitations of traditional antibacterial methods are becoming increasingly apparent: First, the long-term overuse of antibiotics has led to serious bacterial resistance problems, giving rise to the emergence of "superbugs"; second, essential oil-based active ingredients have drawbacks such as high volatility and poor thermal stability; and while metal-based nanomaterials have significant bactericidal effects, their potential cytotoxicity and heavy metal residue risks raise questions about their safety in the food industry and human contact materials. More importantly, most traditional antibacterial agents need to penetrate inside bacteria to exert their effects, which increases the difficulty of sterilization.

[0004] Photodynamic inactivation (PDI) is a non-antibiotic antibacterial strategy that generates reactive oxygen species (such as singlet oxygen) through photoexcitation. 1 O2, superoxide anion radical O2 -Photodynamic antibacterial agents (PDIs) have attracted widespread attention due to their non-specific oxidative damage to bacteria caused by hydroxyl radicals (·OH, etc.). PDIs, with their advantages of rapid bactericidal action, low risk of resistance, and well-defined mechanism of action, are considered a potential alternative to traditional antibacterial agents. However, existing photodynamic antibacterial systems still face key technological bottlenecks. On the one hand, most traditional photosensitizers undergo aggregation-induced quenching (ACQ) in the aggregated state, leading to weakened fluorescence signals and a significant decrease in reactive oxygen species generation efficiency, thus limiting their antibacterial performance under solid-state, thin-film, or high-load conditions. On the other hand, some photosensitizers have poor water solubility, insufficient photostability, or weak targeting of bacteria, making it difficult to achieve efficient and controllable antibacterial effects in complex application environments. These problems severely restrict the practical application and large-scale promotion of photodynamic antibacterial technology.

[0005] In recent years, the emergence of aggregation-induced emission (AIE) materials has provided a new solution to overcome the aforementioned defects of traditional photosensitizers. Photosensitizers with AIE properties exhibit restricted intramolecular motion in the aggregated state, thus maintaining or even enhancing their fluorescence emission and reactive oxygen species (ROS) generation capabilities. Among these, triphenylamine derivatives, due to their non-planar structure, excellent electron-donating properties, and good molecular designability, have become important candidate structural units for constructing AIE-type photodynamic antibacterial agents. However, existing photodynamic antibacterial systems based on triphenylamine structures are still relatively limited, and systematic research on their molecular structure design, photosensitivity regulation, and antibacterial application mechanisms is still lacking.

[0006] Therefore, there is an urgent need to develop a photodynamic antibacterial agent based on triphenylamine derivatives with a well-defined structure, high photodynamic efficiency, and good biosafety, in order to make up for the shortcomings of existing technologies and expand its application in the fields of food safety and biomedicine. Summary of the Invention

[0007] The purpose of this invention is to provide photosensitive compounds based on triphenylamine derivatives, their preparation methods, and applications, in order to help solve or improve the problem that the antibacterial effect of existing photodynamic antibacterial systems based on triphenylamine structures needs to be improved.

[0008] To achieve the above objectives, the present invention provides the following technical solution: a photosensitive compound based on a triphenylamine derivative, wherein the photosensitive compound is compound I or compound II; The structural formula of compound I is: ; The structural formula of compound II is: .

[0009] The present invention also provides a method for preparing a photosensitive compound based on a triphenylamine derivative, which adopts the following technical solution: A method for preparing a photosensitive compound based on a triphenylamine derivative, comprising the following steps: (1) dissolving (E)-3-(5'-(4-(diphenylamino)phenyl)-[2,2'-bithiophene]-5-yl)-2-(pyridin-4-yl)acrylonitrile and the reaction raw material in N,N-dimethylformamide and mixing them, heating to reflux overnight to obtain a reflux liquid; wherein the reaction raw material is 1-bromine -2-(2-(2-methoxyethoxy)ethoxy)ethane or 3-bromo-N-trimethylpropane-1-aminobromide; (2) After cooling the reflux liquid obtained in step (1) to room temperature, remove the solvent N,N-dimethylformamide by rotary evaporation to obtain a black solid; (3) Dissolve the black solid obtained in step (2) in acetone, mix it thoroughly with a saturated potassium hexafluorophosphate solution, and remove the organic solvent by rotary evaporation to obtain a crude product; (4) Recrystallize the crude product obtained in step (3) to obtain the photosensitive compound.

[0010] Preferably, in step (1), the reactants are 1-bromo-2-(2-(2-methoxyethoxy)ethoxy)ethane, and the molar ratio of (E)-3-(5'-(4-(diphenylamino)phenyl)-[2,2'-bithiophene]-5-yl)-2-(pyridin-4-yl)acrylonitrile and 1-bromo-2-(2-(2-methoxyethoxy)ethoxy)ethane is 1:(10-60); or, in step (1), the reactants are 3-bromo-N-trimethylpropane-1-aminobromide, and the molar ratio of (E)-3-(5'-(4-(diphenylamino)phenyl)-[2,2'-bithiophene]-5-yl)-2-(pyridin-4-yl)acrylonitrile and 3-bromo-N-trimethylpropane-1-aminobromide is 10:9; in step (1), the mixture is heated to 175-185°C and refluxed overnight.

[0011] Preferably, in step (1), the ratio of (E)-3-(5'-(4-(diphenylamino)phenyl)-[2,2'-bithiophene]-5-yl)-2-(pyridin-4-yl)acrylonitrile to N,N-dimethylformamide is 0.2 mmol:(10-20 mL); in step (3), the volume ratio of acetone to N,N-dimethylformamide is 10:(10-20), and the volume ratio of acetone to saturated potassium hexafluorophosphate solution is 10:(4-6); in step (3), the stirring time is ≥0.5 h.

[0012] The present invention also provides a photodynamic antibacterial agent, which adopts the following technical solution: a photodynamic antibacterial agent, wherein the components of the photodynamic antibacterial agent include the photosensitive compound based on the triphenylamine derivative as described above.

[0013] The present invention also provides a photodynamic sterilization device, which adopts the following technical solution: a photodynamic sterilization device, wherein the photodynamic sterilization device contains the photosensitive compound or the photodynamic antibacterial agent as described above.

[0014] The present invention also provides an antibacterial film, which adopts the following technical solution: an antibacterial film, wherein the components of the antibacterial film include the photosensitive compound as described above or the photodynamic antibacterial agent as described above.

[0015] Preferably, the antibacterial film further comprises a film-forming agent; the film-forming agent is polyvinyl alcohol.

[0016] The present invention also provides a packaging material, which adopts the following technical solution: a packaging material containing an antibacterial film as described above.

[0017] Beneficial effects: (1) The photosensitive compound based on triphenylamine derivative of the present invention introduces the electron-donating structure of triphenylamine and the conjugated thiophene bridging unit to construct a molecular structure with obvious aggregation-induced emission (AIE) characteristics, so that it can maintain good fluorescence emission performance and photostability under aggregated or solid conditions. This effectively overcomes the defect of traditional photosensitizers that are prone to aggregation-induced quenching (ACQ) in the aggregated state, thereby significantly improving its stability and reliability in photodynamic antibacterial applications.

[0018] (2) The photosensitive compound based on triphenylamine derivatives of the present invention has a high reactive oxygen species (ROS) generation capacity under light conditions. This ROS can cause non-specific oxidative damage to key structures such as bacterial cell membranes, proteins, and nucleic acids, thereby achieving highly efficient sterilization. Experimental results show that the antibacterial agent of the present invention exhibits excellent killing effects against a variety of common pathogenic bacteria, including Staphylococcus aureus, Escherichia coli, and Listeria monocytogenes. It has good broad-spectrum antibacterial properties and does not rely on the traditional antibiotic mechanism of action, thus reducing the risk of inducing bacterial resistance.

[0019] (3) The present invention also provides a method for preparing a photosensitive compound based on a triphenylamine derivative. The method has a clear reaction route and simple steps. The raw materials used are easy to obtain and have low cost. The target product can be obtained by solvent reflux, ion exchange and recrystallization. The purification process is simple, reproducible and has high yield. It is suitable for laboratory preparation and subsequent large-scale production and has high industrial application feasibility.

[0020] (4) The photodynamic antibacterial agent of the present invention can not only be used alone as an antibacterial active ingredient, but can also be further prepared into formulations, materials or integrated into sterilization devices, thus expanding its application forms. Preferably, the photodynamic antibacterial agent of the present invention can also be incorporated into polyvinyl alcohol (PVA) matrix to prepare an antibacterial film, which, while maintaining the original mechanical properties and film-forming properties of the material, endows it with stable and long-lasting antibacterial ability, and is suitable for food packaging, environmental disinfection and medical protection, with clear application prospects. Attached Figure Description

[0021] The accompanying drawings, which form part of this application, are used to provide a further understanding of the invention. The illustrative embodiments of the invention and their descriptions are used to explain the invention and do not constitute an undue limitation of the invention. Wherein: Figure 1 This is a synthetic route diagram of the photosensitive compound based on triphenylamine derivatives of the present invention; Figure 2 The photosensitive compound TBTCP-PEG (compound I) based on triphenylamine derivatives of this invention has a hydrogen nuclear magnetic resonance spectrum. Figure 3 This is the carbon NMR spectrum of TBTCP-PEG (compound I), a photodynamic antibacterial agent based on triphenylamine derivatives in this invention. Figure 4 The photosensitive compound TBTCP-QA (compound II) based on triphenylamine derivatives of this invention has a hydrogen nuclear magnetic resonance spectrum. Figure 5 The carbon NMR spectrum of the photosensitive compound TBTCP-QA (compound II) based on triphenylamine derivatives of this invention is shown below. Figure 6 The UV-Vis spectrum of the photosensitive compound based on triphenylamine derivatives of the present invention in dimethyl sulfoxide and its fluorescence emission spectrum in aqueous solution are shown. Figure 7 The photoluminescence spectra of the photosensitive compounds based on triphenylamine derivatives of the present invention in dimethyl sulfoxide / toluene mixed solvents with different toluene contents are shown. Figure 8 This is a particle size distribution diagram of the photosensitive compound based on triphenylamine derivatives of the present invention; Figure 9 The present invention relates to a photosensitive compound based on a triphenylamine derivative that generates ROS and singlet oxygen under white light irradiation. 1 O2), hydroxyl free radicals, reactive oxygen species ( ) and singlet oxygen ( 1 The performance of O2); where AD is, in order, the ROS intensity and hydroxyl radical reactive oxygen species generated by the photosensitive compound TBTCP-PEG under white light irradiation. Intensity, superoxide anion ( Intensity and singlet oxygen ( 1 O2) intensity; EH represents the ROS intensity of the photosensitive compound TBTCP-QA, and the reactive oxygen species (ROS) of hydroxyl radicals, in descending order. Intensity, superoxide anion ( Intensity and singlet oxygen ( 1 O2) intensity; Figure 10 The photodynamic antibacterial effect of the triphenylamine derivative-based photosensitive compound TBTCP-PEG on Staphylococcus aureus, Listeria monocytogenes and Escherichia coli is shown in the figure. Figure 11 The photodynamic antibacterial effect of the triphenylamine derivative-based photosensitive compound TBTCP-QA on Staphylococcus aureus, Listeria monocytogenes and Escherichia coli is shown in the figure. Figure 12 Visual appearance of polyvinyl alcohol film and polyvinyl alcohol antibacterial film doped with photodynamic antibacterial agent; Figure 13 The image shows the photodynamic antibacterial effect of a polyvinyl alcohol antibacterial film doped with a photodynamic antibacterial agent. Detailed Implementation

[0022] The technical solutions in the embodiments of the present invention will be clearly and completely described below. Obviously, the described embodiments are only a part of the embodiments of the present invention, and not all of them. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention are within the scope of protection of the present invention.

[0023] The present invention will now be described in detail with reference to embodiments. It should be noted that, unless otherwise specified, the embodiments and features described in the embodiments of the present invention can be combined with each other.

[0024] This invention addresses the problem that the antibacterial effect of existing photodynamic antibacterial systems based on triphenylamine structures needs to be improved, by providing a photosensitive compound based on a triphenylamine derivative.

[0025] The photosensitive compound based on the triphenylamine derivative in this embodiment of the invention is compound I or compound II; The molecular structural formula of compound I is: ; The molecular structural formula of compound II is: .

[0026] This invention introduces a triphenylamine electron-donating structure and a conjugated thiophene bridging unit to construct a molecular structure with significant aggregation-induced emission (AIE) characteristics. This allows it to maintain good fluorescence emission performance and photostability under both aggregated and solid-state conditions, effectively overcoming the defect of traditional photosensitizers that are prone to aggregation-induced quenching (ACQ) in the aggregated state. This significantly improves its stability and reliability in photodynamic antibacterial applications. The triphenylamine derivative-based photosensitive compound of this invention has a high reactive oxygen species (ROS) generation capacity under light conditions. This ROS can cause non-specific oxidative damage to key structures such as bacterial cell membranes, proteins, and nucleic acids, achieving highly efficient sterilization. Experimental results show that this triphenylamine derivative-based photosensitive compound exhibits excellent killing effects against various common pathogenic bacteria, including Staphylococcus aureus, Escherichia coli, and Listeria monocytogenes, demonstrating good broad-spectrum antibacterial properties. Furthermore, it does not rely on traditional antibiotic mechanisms of action, reducing the risk of inducing bacterial resistance.

[0027] Furthermore, the photosensitive compound based on triphenylamine derivatives of the present invention has good antibacterial effect, and under white light irradiation, it can kill Staphylococcus aureus and Listeria monocytogenes at significantly lower concentrations (below 0.5 μM; even below 0.25 μM).

[0028] This invention also proposes a method for preparing a photosensitive compound based on a triphenylamine derivative. The method for preparing the photosensitive compound based on a triphenylamine derivative in this embodiment includes the following steps: (1) Dissolving (E)-3-(5'-(4-(diphenylamino)phenyl)-[2,2'-bithiophene]-5-yl)-2-(pyridin-4-yl)acrylonitrile and the reaction raw material in N,N-dimethylformamide and mixing them, heating to reflux overnight to obtain a reflux liquid; the reaction raw material is 1-bromo-2-(2-(2-methyl)-(5'-(4-(diphenylamino)phenyl)-[2,2'-bithiophene]-5-yl)-2-(pyridin-4-yl)acrylonitrile and the reaction raw material in N,N-dimethylformamide and mixing them, heating to reflux overnight to obtain a reflux liquid; (1) Ethoxy(ethoxy) ethane or 3-bromo-N-trimethylpropane-1-aminobromide; (2) After cooling the reflux liquid obtained in step (1) to room temperature, remove the solvent N,N-dimethylformamide by rotary evaporation to obtain a black solid; (3) Dissolve the black solid obtained in step (2) in acetone, mix it thoroughly with a saturated potassium hexafluorophosphate solution, and remove the organic solvent by rotary evaporation to obtain a crude product; (4) Recrystallize the crude product obtained in step (3) (preferably, recrystallize multiple times) to obtain the photosensitive compound.

[0029] The present invention provides a method for preparing photosensitive compounds based on triphenylamine derivatives (process route diagram as follows). Figure 1 The reaction route (shown) is clear and the steps are simple. The raw materials used are readily available and low in cost. The target product can be obtained through conventional solvent reflux, ion exchange and recrystallization. The purification process is simple, reproducible and has a high yield. It is suitable for laboratory preparation and subsequent large-scale production and has high feasibility for industrial application.

[0030] In a preferred embodiment of the method for preparing the photosensitive compound based on triphenylamine derivatives of the present invention, in step (1), the reaction raw materials are 1-bromo-2-(2-(2-methoxyethoxy)ethoxy)ethane, (E)-3-(5'-(4-(diphenylamino)phenyl)-[2,2'-bithiophene]-5-yl)-2-(pyridin-4-yl)acrylonitrile and 1-bromo-2-(2-(2-methoxyethoxy)ethoxy)ethane in a molar ratio of 1:(10-60) (e.g., 1:10, 1:20, 1:30, 1:40, 1:50 or 1:60; wherein, if the proportion of 1-bromo-2-(2-(2-methoxyethoxy)ethoxy)ethane is too high, it is easy to waste the raw materials). If the amount of 1-bromo-2-(2-(2-methoxyethoxy)ethoxy)ethane is too low, the reaction will be incomplete and subsequent separation will be difficult. Alternatively, in step (1), the reaction raw material is 3-bromo-N-trimethylpropane-1-aminobromide, and the molar ratio of (E)-3-(5'-(4-(diphenylamino)phenyl)-[2,2'-bithiophene]-5-yl)-2-(pyridin-4-yl)acrylonitrile and 3-bromo-N-trimethylpropane-1-aminobromide is 10:9 (if the molar ratio of the two is not appropriate, it will affect the subsequent separation and purification). In step (1), the mixture is heated to 175-185℃ (e.g., 175℃, 178℃, 180℃, 182℃ or 185℃) and refluxed overnight.

[0031] In a preferred embodiment of the method for preparing the photosensitive compound based on triphenylamine derivatives of the present invention, in step (1), the ratio of (E)-3-(5'-(4-(diphenylamino)phenyl)-[2,2'-bithiophene]-5-yl)-2-(pyridin-4-yl)acrylonitrile to N,N-dimethylformamide is 0.2 mmol:(10-20 mL) (e.g., 0.2 mmol:10 mL, 0.2 mmol:12 mL, 0.2 mmol:15 mL, 0.2 mmol:17 mL, or 0.2 mmol:20 mL); in step (3) The volume ratio of acetone to N,N-dimethylformamide is 10:(10-20) (e.g., 10:10, 10:12, 10:15, 10:17 or 10:20), and the volume ratio of acetone to saturated potassium hexafluorophosphate solution is 10:(4-6) (e.g., 10:4, 10:4.5, 10:5, 10:5.5 or 10:6); in step (3), the stirring and mixing time is ≥0.5h (preferably, the stirring and mixing time in step (3) is 0.5-1h; for example, 0.5h, 0.6h, 0.7h, 0.8h, 0.9h or 1h). Among these, the stirring and mixing in step (3) is uniform, which is beneficial for ion exchange.

[0032] The present invention also proposes a photodynamic antibacterial agent, wherein the components of the photodynamic antibacterial agent of the present invention include the photosensitive compound based on the triphenylamine derivative as described above.

[0033] The present invention also proposes a photodynamic sterilization device, wherein the photodynamic sterilization device of the present invention contains the photosensitive compound or the photodynamic antibacterial agent as described above.

[0034] The present invention also proposes an antibacterial film, wherein the antibacterial film of the present invention comprises the photosensitive compound as described above or the photodynamic antibacterial agent as described above.

[0035] In a preferred embodiment of the antibacterial film of the present invention, the antibacterial film further comprises a film-forming agent; the film-forming agent is polyvinyl alcohol.

[0036] The present invention also proposes a packaging material, wherein the packaging material of the present invention embodiment contains an antibacterial film as described above.

[0037] The following detailed embodiments illustrate the photosensitive compounds based on triphenylamine derivatives of the present invention, their preparation methods, and applications.

[0038] The sources of the main raw materials used in the following embodiments: There are no particular restrictions on the source of any of the raw materials used in this invention; they can be purchased from the market or prepared using conventional methods well known to those skilled in the art. Specifically: (E)-3-(5'-(4-(diphenylamino)phenyl)-[2,2'-bithiophene]-5-yl)-2-(pyridin-4-yl)acrylonitrile was prepared according to the method described in the literature Ping Yang, Ya-Feng Song, et al. AIE-doped agar-based photodynamicsterilization film for antimicrobial food wrapping[J]. LWT-Food Science and Technology, 202 (2024) 116330; The remaining raw materials were purchased from Bid Pharmaceuticals.

[0039] Example 1 The photosensitive compound based on the triphenylamine derivative in this embodiment is TBTCP-PEG (compound I), and its structural formula is as follows: .

[0040] The synthetic route of the photosensitive compound based on triphenylamine derivatives in this embodiment is as follows:

[0041] The preparation method of the photosensitive compound based on triphenylamine derivatives in this embodiment includes the following steps: (1) Add (E)-3-(5'-(4-(diphenylamino)phenyl)-[2,2'-bithiophene]-5-yl)-2-(pyridin-4-yl)acrylonitrile (107.5 mg, 0.2 mmol), 1-bromo-2-(2-(2-methoxyethoxy)ethoxy)ethane (454.2 mg, 10 mmol) and 15 mL of N,N-dimethylformamide (DMF) to a 50 mL round-bottom flask; heat the mixture to 180 °C and reflux overnight to obtain the reflux solution; (2) After the reflux liquid is cooled to room temperature, the solvent is removed by rotary evaporation under vacuum to obtain a black solid; (3) Dissolve the obtained black solid in 10 mL of acetone and mix it with saturated KPF6 solution (dissolved in 5 mL of acetone). Stir at room temperature for 1 h and remove the organic solvent by vacuum to obtain the crude product. (4) The crude product was recrystallized multiple times using petroleum ether / dichloromethane and diethyl ether / methanol (the number of recrystallizations with petroleum ether / dichloromethane was 2-3 times, and the number of recrystallizations with diethyl ether / methanol was also 2-3 times; specifically, the crude product obtained in the previous step was first dissolved in dichloromethane, and then precipitated with petroleum ether to obtain the purified product; then dissolved in methanol, and then precipitated with diethyl ether to obtain the secondary purified product), and finally a black solid was obtained, which is the photosensitive compound TBTCP-PEG based on the triphenylamine derivative in this embodiment. The yield of the photosensitive compound based on the triphenylamine derivative prepared by this preparation method was 90%.

[0042] The prepared photosensitive compound TBTCP-PEG based on triphenylamine derivatives was analyzed and characterized by nuclear magnetic resonance spectroscopy. (See below) Figure 2-3 The data is as follows: 1 H NMR (400 MHz, DMSO-d6): δ ppm = 9.01 (s, 1H), 8.97 (d, J = 6.4 Hz, 2H), 8.30 (d, J = 6.4 Hz, 2H), 7.98 (d, J = 4.4 Hz, 1H), 7.69-7.63 (m, 4H),7.51(d, J = 2.4 Hz, 1H), 7.35 (t, J = 8.4 Hz, 4H), 7.13-7.06 (m, 6H), 6.97(d, J = 8.4 Hz, 2H), 4.74-4.73 (m, 2H), 3.91-3.89 (m, 2H), 3.57-3.55 (m, 2H),3.47-3.42 (m, 6H), 3.22 (s, 3H); 13 C NMR (100 MHz, DMSO-d6): δ ppm = 151.0, 149.2, 148.5, 148.0, 147.6,146.2, 144.8, 143.7, 136.2, 134.4, 131.3, 130.3, 128.1, 127.5, 126.5, 126.2,125.9, 125.5, 123.5, 123.4, 117.9, 100.5, 72.6, 71.1, 70.9, 70.8, 61.0, 59.5.

[0043] The antibacterial membrane of this embodiment was prepared by the following steps: 16g of PVA was dissolved in 184mL of distilled water and stirred at 95°C for 6h; then, 1.656mg of TBTCP-PEG was added and stirred for 1h; the mixture was defoamed in an ultrasonic bath for 0.5h; finally, the solution was carefully poured into a mold and dried at room temperature for 2d to obtain the antibacterial membrane of this embodiment.

[0044] Example 2 The photosensitive compound based on the triphenylamine derivative in this embodiment is TBTCP-QA (compound II), and its structural formula is as follows: .

[0045] The synthetic route of the photosensitive compound based on triphenylamine derivatives in this embodiment is as follows: .

[0046] The preparation method of the photosensitive compound based on triphenylamine derivatives in this embodiment includes the following steps: (1) Add (E)-3-(5'-(4-(diphenylamino)phenyl)-[2,2'-bithiophene]-5-yl)-2-(pyridin-4-yl)acrylonitrile (107.5 mg, 0.2 mmol), 3-bromo-N-trimethylpropane-1-aminobromide (47 mg, 0.18 mmol) and 15 mL of N,N-dimethylformamide (DMF) to a 50 mL round-bottom flask; heat the mixture to 180 °C and reflux overnight to obtain the reflux solution; (2) After the reflux liquid is cooled to room temperature, the solvent is removed by rotary evaporation to obtain a black solid; (3) Dissolve the obtained black solid in 10 mL of acetone and mix it with saturated KPF6 solution (dissolved in 5 mL of acetone). Stir at room temperature for 1 h and remove the organic solvent by rotary evaporation to obtain the crude product. (4) The crude product was recrystallized multiple times using diethyl ether / methanol (specifically, the crude product was first dissolved in methanol and then precipitated with diethyl ether to obtain the purified product), and the final black solid obtained was the photosensitive compound TBTCP-QA based on the triphenylamine derivative in this embodiment. The yield of the photosensitive compound based on the triphenylamine derivative prepared by this method was 92%.

[0047] The photosensitive compound TBTCP-QA based on triphenylamine derivatives was analyzed and characterized by nuclear magnetic resonance spectroscopy. (See below) Figure 4-5 The data is as follows: 1 H NMR (400 MHz, DMSO-d6): δ ppm = 9.02-9.00 (m, 2H), 8.97 (s, 1H), 8.33 (d, J = 6.4 Hz, 2H), 7.95 (d, J = 4.4 Hz, 1H), 7.64 (t, J = 4.4 Hz, 2H),7.59 (d, J = 8.4 Hz, 2H), 7.47 (d, J = 3.6 Hz, 1H), 7.33 (t, J = 8.0 Hz, 4H),7.10 (t, J = 7.2 Hz, 2H), 7.50 (d, J = 7.6 Hz, 4H), 6.93 (d, J = 8.4 Hz, 2H),4.59 (t, J = 7.2 Hz, 2H), 3.39-3.35 (m, 2H), 3.08 (s, 9H), 2.44-2.41 (m, 2H); 13 C NMR (100 MHz, DMSO-d6): δ ppm = 150.7, 148.7, 148.2, 147.6, 147.2,145.7, 144.7, 143.2, 135.8, 133.9, 130.7, 130.1, 127.7, 127.1, 126.2, 125.7,125.5, 124.9, 123.4, 123.2, 117.5, 100.1, 62.8, 57.8, 53.5, 25.1.

[0048] The antibacterial membrane of this embodiment was prepared by the following steps: 16g of PVA was dissolved in 184mL of distilled water and stirred at 95°C for 6h; then, 1.656mg of TBTCP-QA was added and stirred for 1h; the mixture was defoamed in an ultrasonic bath for 0.5h; finally, the solution was carefully poured into a mold and dried at room temperature for 2d to obtain the antibacterial membrane of this embodiment.

[0049] Experimental Example I. Optical and physical property testing of photosensitive compounds based on triphenylamine derivatives: 1. UV absorption and fluorescence tests in different solvents: Figure 6 The UV-Vis absorption spectrum of a triphenylamine derivative-based photosensitive compound (20 μM) in dimethyl sulfoxide (DMSO) and its fluorescence emission spectrum in aqueous solution are shown. Figure 6 It can be seen that the photodynamic antibacterial agents TBTCP-PEG and TBTCP-QA both exhibit significant absorption characteristics in the visible light region, with their maximum absorption peak located at approximately 550 nm, indicating that these two compounds can effectively absorb visible light as an excitation source. This absorption wavelength falls within the ideal wavelength range for commonly used photodynamic applications, which is beneficial for excitation under mild lighting conditions, thereby enhancing their application potential in photodynamic antibacterial processes. Simultaneously, they still exhibit detectable fluorescence emission in aqueous systems, indicating that these photodynamic antibacterial agents possess a certain optical response capability in aquatic environments.

[0050] Figure 7 The photoluminescence spectra of photosensitive compounds based on triphenylamine derivatives in DMSO / toluene mixed solvent systems with different toluene volume fractions are shown. Figure 7 It can be seen that as the content of the polar solvent DMSO gradually decreases and the content of the nonpolar solvent toluene gradually increases in the system, the emission peak positions of TBTCP-PEG and TBTCP-QA show a gradual blue shift trend, while the fluorescence intensity is significantly enhanced. This phenomenon can be attributed to the twisted intramolecular charge transfer (TICT) effect in the molecule, that is, the change in solvent polarity affects the excited-state configuration and radiative transition process of the molecule. When the volume fraction of toluene reaches 99%, the fluorescence emission intensity of the photosensitive compounds TBTCP-PEG and TBTCP-QA reaches its maximum at 575 nm and 560 nm, respectively, exhibiting typical aggregation-induced emission (AIE) characteristics. The above results indicate that the nonradiative energy transition of this triphenylamine derivative-based photosensitive compound is suppressed in the aggregated state, which is beneficial for maintaining high fluorescence emission and photodynamic activity. This is of great significance for its photodynamic antibacterial application on bacterial surfaces or in aggregated environments.

[0051] 2. Particle size test: Figure 8This is a particle size distribution diagram of the photosensitive compounds based on triphenylamine derivatives. To characterize the dispersion state of the photosensitive compounds in solution (solvent: water), a particle size analyzer was used to test the particle size of the 10 μM photosensitive compounds. The test results show that the particle sizes of the photosensitive compounds TBTCP-PEG and TBTCP-QA are mainly distributed around 196 nm and 225 nm, respectively, with a relatively concentrated particle size distribution, indicating good dispersibility and stability in the solution system. This particle size range is beneficial for the uniform doping of the triphenylamine derivative-based photosensitive compounds of this invention into other carrier materials, such as polyvinyl alcohol films, or for their uniform dispersion in spraying systems, thereby achieving effective loading on solid surfaces and providing a good physical basis for their further use in antibacterial materials and related applications.

[0052] 3. Photodynamic activity test: Figure 9 The photosensitive compounds based on triphenylamine derivatives in Examples 1-2 generate ROS and hydroxyl radicals under white light irradiation. ), superoxide anion ( ) and singlet oxygen ( 1 Test results of O2 performance.

[0053] Test methods: The total ROS generation of TBTCP-PEG and TBTCP-QA was measured using 2',7'-dichlorodihydrofluorescein diacetate (DCFH-DA) as an indicator; singlet oxygen (ROS) was detected using 9,10-anthracene-neodymyl-bis(methylene)dimalonic acid (ABDA) as an indicator. 1 The generation of O2; using hydroxyphenylfluorescein (HPF) as an indicator, the detection of hydroxyl radicals (O2) The generation of superoxide anions (SAO) was observed; dihydroethidium (DHE) was used as an indicator to detect SAO anions. The generation of ).

[0054] Under white light illumination, the absorbance of ABDA decreased significantly with prolonged illumination time, while the fluorescence of DCFH-DA, DHE, and HPF gradually increased, indicating the generation of a large amount of singlet oxygen. 1 O2), hydroxyl radicals ( ) and superoxide anion ( The above results indicate that the photosensitive compounds TBTCP-PEG and TBTCP-QA, based on triphenylamine derivatives, possess excellent ROS production capabilities and can efficiently generate ROS. 1 O2, and .

[0055] II. The bactericidal effect of photosensitive compounds based on triphenylamine derivatives: Figure 10 and Figure 11 The photodynamic antibacterial effects of the triphenylamine derivative photosensitive compounds TBTCP-PEG and TBTCP-QA on Staphylococcus aureus, Listeria monocytogenes and Escherichia coli are shown in the figure.

[0056] Test method: 100 μL (10 9 Bacteria (including Escherichia coli, Staphylococcus aureus, and Listeria monocytogenes) at CFU / mL were dispersed in solutions containing different concentrations of TBTCP-PEG and TPTCP-QA and incubated at 37°C and 200 rpm. A portion of the solution was exposed to white light (60 mW / cm²). 2 One portion was kept in the dark for 5 minutes (10 minutes for E. coli); the other portion was kept in the dark for 30 minutes. Then, 100 μL (10 4 Bacteria (CFU / mL) were sprayed onto LB agar plates (Listeria monocytogenes on TSA-YE plates). All LB agar plates containing the treated bacteria were then incubated at 37°C for 12 h, followed by imaging to calculate the number of colony-forming units (CFU). The experimental results are shown below. Figure 10 and Figure 11 As shown.

[0057] As shown in the figure, with the increase of the concentrations of the photodynamic antibacterial agents TBTCP-PEG and TPTCP-QA, under white light irradiation, Staphylococcus aureus and Listeria monocytogenes were almost completely killed, while the kill rate of Escherichia coli also reached over 40%. These results indicate that the photosensitive compound based on triphenylamine derivatives of this invention exhibits good photodynamic antibacterial activity against a variety of bacteria under light irradiation.

[0058] Table 1. Results of photodynamic antibacterial activity test of TBTCP-PEG

[0059] Table 2. Results of photodynamic antibacterial activity test of TBTCP-QA

[0060] III. The bactericidal effect of PVA antibacterial films doped with photosensitive compounds based on triphenylamine derivatives: To verify the feasibility of the photosensitive compound based on triphenylamine derivatives of this invention in practical applications such as food packaging, the photosensitive compound based on triphenylamine derivatives was doped into a polyvinyl alcohol (PVA) matrix to prepare a polymeric film material with photodynamic antibacterial function. This antibacterial film can be used as a functional packaging material to extend the shelf life of food and improve food safety.

[0061] Pure PVA films were prepared as a control (the preparation method was the same as in Examples 1-2, the only difference from the antibacterial films in Examples 1-2 was that the photosensitive compound based on triphenylamine derivatives in Examples 1 and 2 was omitted; all other steps remained the same).

[0062] A comparison of the appearances of pure PVA film, the antibacterial film of Example 1 (PVA / TBTCP-PEG), and the antibacterial film of Example 2 (PVA / TBTCP-QA) is shown below. Figure 12 As shown.

[0063] Depend on Figure 12 It can be seen that the PVA film doped with the photosensitive compound based on the triphenylamine derivative of this invention still has good light transmittance and does not significantly affect the visibility of the coated object. Furthermore, the water resistance, air permeability, tensile strength, and morphological characteristics of the prepared antibacterial film were tested. The results show that after introducing the photosensitive compounds of Examples 1 and 2, the mechanical properties and film-forming properties of the PVA antibacterial film were not significantly negatively affected compared to the pure PVA film, and it will not affect its normal use in food packaging and other application scenarios.

[0064] The antibacterial properties of the antimicrobial membranes from Examples 1-2 were further evaluated using colony counting. The specific method is as follows: To determine the antibacterial properties of the membranes using colony counting, first, the membranes were cut into squares (1cm × 1cm) and placed under ultraviolet light for 0.5 hours (pre-sterilized to ensure no interference from other microorganisms). Then, in a 6-well plate, 100 μL of bacterial suspension (1 × 10⁻⁶) was added to two overlapping membranes. 5 CFU / mL, Staphylococcus aureus). Then use white light (60mW / cm). 2 Irradiate for 5 min, and place the control group in the dark for 30 min. Finally, add 1 mL of PBS to each well, spread 0.1 mL of the mixed solution on an agar plate, and incubate at 37°C for 18 h.

[0065] Experimental results are as follows Figure 13 As shown. By Figure 13 It can be seen that, under white light irradiation, the PVA antibacterial film doped with photodynamic antibacterial agents TBTCP-PEG and TPTCP-QA has a significant killing effect on Staphylococcus aureus. The bacteria in the treatment group were almost completely killed (antibacterial rate 100%), which fully demonstrates that the antibacterial film of the present invention has good photodynamic antibacterial performance in practical applications.

[0066] The above description is merely a preferred embodiment of the present invention and is not intended to limit the invention. Various modifications and variations can be made to the present invention by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. A photosensitive compound based on a triphenylamine derivative, characterized in that, The photosensitive compound is compound I or compound II; The structural formula of compound I is: ; The structural formula of compound II is: .

2. The method for preparing the photosensitive compound based on a triphenylamine derivative as described in claim 1, characterized in that, Includes the following steps: (1) Dissolve (E)-3-(5'-(4-(diphenylamino)phenyl)-[2,2'-bithiophene]-5-yl)-2-(pyridin-4-yl)acrylonitrile and the reaction raw material in N,N-dimethylformamide and mix well. Heat to reflux overnight to obtain a reflux liquid; the reaction raw material is 1-bromo-2-(2-(2-methoxyethoxy)ethoxy)ethane or 3-bromo-N-trimethylpropane-1-aminobromide; (2) After cooling the reflux liquid obtained in step (1) to room temperature, remove the solvent N,N-dimethylformamide by rotary evaporation to obtain a black solid; (3) Dissolve the black solid obtained in step (2) in acetone, mix it thoroughly with saturated potassium hexafluorophosphate solution, and remove the organic solvent by rotary evaporation to obtain the crude product; (4) The crude product obtained in step (3) is recrystallized to obtain the photosensitive compound.

3. The method for preparing the photosensitive compound based on the triphenylamine derivative as described in claim 2, characterized in that, In step (1), the reactants are 1-bromo-2-(2-(2-methoxyethoxy)ethoxy)ethane, and the molar ratio of (E)-3-(5'-(4-(diphenylamino)phenyl)-[2,2'-bithiophene]-5-yl)-2-(pyridin-4-yl)acrylonitrile and 1-bromo-2-(2-(2-methoxyethoxy)ethoxy)ethane is 1:(10-60); or, In step (1), the reaction raw material is 3-bromo-N-trimethylpropane-1-aminobromide, and the molar ratio of (E)-3-(5'-(4-(diphenylamino)phenyl)-[2,2'-bithiophene]-5-yl)-2-(pyridin-4-yl)acrylonitrile to 3-bromo-N-trimethylpropane-1-aminobromide is 10:9; In step (1), heat to 175-185°C and reflux overnight.

4. The method for preparing the photosensitive compound based on the triphenylamine derivative as described in claim 2, characterized in that, In step (1), the ratio of (E)-3-(5'-(4-(diphenylamino)phenyl)-[2,2'-bithiophene]-5-yl)-2-(pyridin-4-yl)acrylonitrile to N,N-dimethylformamide is 0.2 mmol:(10-20 mL); In step (3), the volume ratio of acetone to N,N-dimethylformamide is 10:(10-20), and the volume ratio of acetone to saturated potassium hexafluorophosphate solution is 10:(4-6). In step (3), the mixing time is ≥0.5h.

5. A photodynamic antibacterial agent, characterized in that, The photodynamic antibacterial agent comprises a photosensitive compound based on a triphenylamine derivative as described in claim 1.

6. A photodynamic sterilization device, characterized in that, The photodynamic sterilization device contains the photosensitive compound as described in claim 1 or the photodynamic antibacterial agent as described in claim 5.

7. An antibacterial film, characterized in that, The antibacterial film comprises the photosensitive compound as described in claim 1 or the photodynamic antibacterial agent as described in claim 5.

8. The antibacterial film as described in claim 7, characterized in that, The antibacterial film also includes a film-forming agent; the film-forming agent is polyvinyl alcohol.

9. A packaging material, characterized in that, The packaging material contains the antimicrobial film as described in claim 7 or 8.

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