Aie active photosensitizer, preparation method and application thereof

Abstract

The application discloses an AIE active photosensitizer and a preparation method and application thereof, adopts asymmetric molecular modification design, and designs a targeted compound with a donor-π-acceptor (D-π-A) structure. Different molecular segments have specific functions, DMA and TPA are selected as electron donors, the DMA unit can endow the photosensitizer with pH response behavior, and the TPA unit makes the photosensitizer have better AIE properties. A pyridine ring with a positive charge as an acceptor is used to manufacture a stronger intramolecular charge transfer state, and induce the generation of ROS. A low-dose photosensitizer can completely kill cancer cells, well inhibit tumor growth, and shows the potential for developing an efficient PDT technology.

Description

Technical Field

[0001] This invention relates to the field of photodynamic therapy technology, and more particularly to photosensitizers. Background Technology

[0002] Fluorescence imaging-guided photodynamic therapy (PDT) has garnered significant attention in clinical disease treatment due to its outstanding advantages, including non-invasiveness, low treatment resistance, real-time treatment visualization, and good spatiotemporal selectivity. Photosensitizers (PS), as a crucial component of the PDT process, have seen a significant research focus in their development as highly efficient and multifunctional agents. Photosensitizers containing positive charges in their π-conjugated molecular backbones have attracted increasing attention in PDT due to their superior targeting ability to mitochondria and their efficient generation of reactive oxygen species (ROS). However, the strong intramolecular charge transfer and intermolecular dipole-dipole interactions in charged photosensitizers often quench fluorescence. Traditionally, commercial photosensitizers, such as porphyrins, methylene blue, and some derivatives of rose bengal, are constructed from disc-shaped fused aromatic rings. Although they have the ability to generate effective reactive oxygen species (ROS), satisfactory absorption wavelengths, and mild dark cytotoxicity, their rigid molecular structure makes them prone to aggregation in the physiological environment through spontaneous π-π stacking interactions between adjacent molecules. This can lead to adverse behaviors such as fluorescence quenching and reduced ROS generation efficiency, which seriously affect the effectiveness of clinical disease diagnosis and treatment.

[0003] Simultaneously enhancing the ROS generation efficiency and fluorescence of charged photosensitizers is beneficial for real-time monitoring of drug dynamics and improving therapeutic efficacy, but this presents significant challenges. In contrast to traditional disc-shaped photosensitizers (PSs), next-generation photosensitizers with aggregation-induced emission (AIE) properties are typically constructed from rotating aromatic rings, which can simultaneously improve fluorescence and ROS generation efficiency from single molecules to aggregates. Brightness and ROS generation efficiency can be well-designed through purposeful tuning of the molecular structure. For example, more flexible aromatic rotors in the photosensitizer backbone often enhance fluorescence during aggregation, while strong intramolecular charge transfer effects are often designed to improve ROS generation efficiency and achieve near-infrared red fluorescence. Besides molecular structure design, host-guest interactions are an effective method for improving the performance of AIE-active photosensitizers. For instance, the co-assembly of amphiphilic polymers and AIE-active photosensitizers to provide polymer nanoparticles with better water dispersibility, higher brightness, and ROS generation efficiency has shown great promise due to their better biocompatibility and ideal tumor retention efficiency. Potential for biomedical applications. Leveraging the unique advantages of fabricating photosensitizer core and polymer shell structures, several functional polymers with specific structures have been designed to encapsulate AIE-active photosensitizers to enhance performance. Tang et al. reported that rigid coralene units can improve intraparticle rigidity, which is beneficial for simultaneously enhancing the fluorescence and ROS generation of nanoparticles loaded with AIE-active photosensitizers. Due to the overexpression of glutathione (GSH) in acidic environments and tumor microenvironments (TMEs), several pH- and GSH-responsive polymers were designed to encapsulate AIE-active photosensitizers. The resulting smart polymer nanoparticles were decomposed, releasing the photosensitizer to enhance ROS generation. Therefore, it can be seen that polymer modification of AIE-active photosensitizers to improve specific properties, particularly fluorescence and ROS generation efficiency, is particularly viable, but usually requires the pre-synthesis of complex functional polymers.

[0004] Therefore, there is an urgent need for simple strategies to simultaneously improve the fluorescence and ROS generation efficiency of AIE-active photosensitizers. It is anticipated that directly utilizing inherent stimulus-response conditions in the physiological environment, such as pH and proteins, can enhance the fluorescence and ROS generation of AIE-active photosensitizers. If we want to design stimulus-responsive AIE-active photosensitizers using inherent physiological stimuli, a clear and systematic study of the relationship between molecular structure and photosensitizer performance is essential. Summary of the Invention

[0005] The purpose of this invention is to provide an AIE-active photosensitizer, its preparation method, and its application, in order to solve the problem of how to simultaneously enhance the fluorescence and ROS generation of the AIE-active photosensitizer.

[0006] To achieve the above objectives, the present invention adopts the following technical solution:

[0007] like Figure 1 As shown, asymmetric molecular modification was used to design targeted compounds with donor-π-acceptor (D-π-A) structures. According to our design philosophy, different molecular segments have specific functions. For example, DMA and TPA were chosen as electron donors; the DMA unit imparts pH-responsive behavior to the photosensitizer, while the TPA unit enhances its AIE properties. The pyridine ring, with a positive charge as the acceptor, is used to create a stronger intramolecular charge transfer state, inducing ROS generation. Fusion π-bridges of Np, An, and BZ exhibiting different electron-donating / electron-withdrawing abilities were selected to modulate the fluorescence color and ROS generation efficiency of the photosensitizer. All photosensitizers were synthesized using the classic Suzuki and Knoevenagel reactions. 1 H / 13 C10 NMR spectroscopy fully demonstrated their chemical structure, which proves the successful preparation of the target product.

[0008] AIE active photosensitizers are selected from one of the following structures:

[0009]

[0010] This invention also provides a method for preparing an AIE-active photosensitizer. The preparation process includes: placing 4-(dimethylamino)phenylboronic acid pinacol ester / triphenylamine boric acid, 1,4-dibromonaphthalene, and Pd(PPh3)4 into a reaction vessel, and reacting with THF and K2CO3 aqueous solution under nitrogen protection to obtain intermediate product 1; adding intermediate product 1, 4-formylphenylboronic acid, and Pd(PPh3)4 into a reaction vessel, and reacting with THF and K2CO3 aqueous solution under nitrogen protection to obtain intermediate product 2; dissolving intermediate product 2 and 1,4-dimethylpyridine iodide in a solvent, and adding a few drops of piperidine to the mixture to react and obtain the AIE-active photosensitizer.

[0011] Furthermore, the preparation process of the DMANpPy includes:

[0012] 5 mmol of 1,4-dibromonaphthalene and 6 mmol of 4-(dimethylamino)phenylboronic acid pinacol ester, and 0.02 equivalents of Pd(PPh3)4 (based on bromine substitution) were placed in a reaction vessel, purged with N2, and under nitrogen protection, 20 mL of THF and 2 M, 8 mL of K2CO3 aqueous solution were injected into the reaction vessel. The mixture was refluxed overnight and purified to obtain DMANp-Br.

[0013] 2 mmol of DMANp-Br and 3 mmol of 4-formylphenylboronic acid, and 0.02 equivalents of Pd(PPh3)4 based on bromine substitution were placed in a reaction vessel, which was then filled with N2. Under nitrogen protection, 20 mL of THF and 2 M, 8 mL of K2CO3 aqueous solution were injected into the reaction vessel, and the mixture was refluxed overnight to obtain DMANp-CHO.

[0014] 0.5 mmol of DMANp-CHO and 0.7 mmol of 1,4-dimethylpyridine-1-iodide were dissolved in a THF / methanol mixture with a volume of 4 / 12. A few drops of piperidine were added to the mixture and the mixture was refluxed for 12 hours. DMANpPy was obtained by purification.

[0015] Further, the preparation process of TPANpPy includes: placing 5 mmol of 1,4-dibromonaphthalene and 6 mmol of triphenylamine boric acid, and 0.02 equivalents of Pd(PPh3)4 (based on bromine substitution) into a reaction vessel, purging with N2, and injecting 20 mL of THF and 2 M, 8 mL of K2CO3 aqueous solution into the reaction vessel under nitrogen protection, refluxing overnight, and purifying to obtain TPANp-Br;

[0016] 2 mmol of TPANp-Br and 3 mmol of 4-formylphenylboronic acid, and 0.02 equivalents of Pd(PPh3)4 based on bromine substitution were placed in a reaction vessel, purged with N2, and under nitrogen protection, 20 mL of THF and 2 M, 8 mL of K2CO3 aqueous solution were injected into the reaction vessel, and the reaction was refluxed overnight to obtain TPANp-CHO.

[0017] 0.5 mmol of TPANp-CHO and 0.7 mmol of 1,4-dimethylpyridine-1-iodide were dissolved in a THF / methanol mixture with a volume of 4 / 12. A few drops of piperidine were added to the mixture and the mixture was refluxed for 12 hours to obtain TPANpPy.

[0018] This invention also provides another method for preparing an AIE-active photosensitizer. The preparation process includes: placing 9,10-dibromoanthracene, 4-formylphenylboronic acid, and Pd(PPh3)4 into a reaction vessel; under nitrogen protection, injecting an aqueous solution of THF and K2CO3 into the reaction vessel to obtain intermediate product a; placing 4-(dimethylamino)phenylboronic acid pinacol ester / triphenylamineboronic acid, intermediate product a, and Pd(PPh3)4 into a reaction vessel; under nitrogen protection, injecting an aqueous solution of THF and K2CO3 into the reaction vessel to obtain intermediate product b; dissolving intermediate product b and 1,4-dimethylpyridine iodide in a solvent; and adding a few drops of piperidine to the mixture to react and obtain the photosensitizer.

[0019] Furthermore, the preparation process of DMAAnPy includes:

[0020] 5 mmol of 9,10-dibromoanthracene and 6 mmol of 4-formylphenylboronic acid, and 0.02 equivalents of Pd(PPh3)4 based on bromine substitution were placed in a reaction vessel, purged with N2, and under nitrogen protection, 20 mL of THF and 2 M, 8 mL of K2CO3 aqueous solution were injected into the reaction vessel, and the reaction was refluxed overnight to obtain BrAn-CHO.

[0021] 2 mmol of BrAn CHO and 3 mmol of 4-(dimethylamino)phenylboronic acid pinacol ester and 0.02 equivalents of Pd(PPh3)4 (based on bromine substitution) were placed in a reaction vessel, purged with N2, and under nitrogen protection, 20 mL of THF and 2 M, 8 mL of K2CO3 aqueous solution were injected into the reaction vessel. The mixture was refluxed overnight and purified to obtain DMAAn-CHO.

[0022] 0.5 mmol of DMAAn CHO and 0.7 mmol of 1,4-dimethylpyridine-1-iodide were dissolved in a THF / methanol mixture with a volume of 4 / 12. A few drops of piperidine were added to the mixture and the mixture was refluxed for 12 hours to obtain DMAAnPy.

[0023] Further, the preparation process of TPAAnPy includes: placing 2 mmol of BrAn CHO and 3 mmol of triphenylamine boric acid, and 0.02 equivalents of Pd(PPh3)4 (based on bromine substitution) into a reaction vessel, filling it with N2, and under nitrogen protection, injecting 20 mL of THF and 2M, 8 mL of K2CO3 aqueous solution into the reaction vessel, refluxing the reaction overnight, and purifying to obtain TPAAn-CHO;

[0024] 0.5 mmol of TPAAn-CHO and 0.7 mmol of 1,4-dimethylpyridine-1-iodide were dissolved in a THF / methanol mixture with a volume of 4 / 12. A few drops of piperidine were added to the mixture and the mixture was refluxed for 12 hours to purify TPAAnPy.

[0025] This invention also provides another method for preparing an AIE-active photosensitizer, the process comprising:

[0026] 4,7-Dibromo-2,1,3-benzothiadiazole, 4-(dimethylamino)phenylboronic acid pinacol ester, and Pd(PPh3)4 were placed in a reaction vessel. Under nitrogen protection, THF and K2CO3 aqueous solution were injected into the reaction vessel to react and obtain intermediate product I.

[0027] Intermediate product I, 4-formylphenylboronic acid, and Pd(PPh3)4 were placed in a reaction vessel. Under nitrogen protection, THF and K2CO3 aqueous solution were injected into the reaction vessel to react and obtain intermediate product II.

[0028] Intermediate product II and 1,4-dimethylpyridine iodide were dissolved in a solvent, and a few drops of piperidine were added to the mixture to react and obtain a photosensitizer.

[0029] Further, the preparation process of DMABZPy includes: placing 5 mmol of 4,7-dibromo-2,1,3-benzothiadiazole and 6 mmol of 4-(dimethylamino)phenylboronic acid pinacol ester, and 0.02 equivalents of Pd(PPh3)4 (based on brominated derivative) into a reaction vessel, purging with N2, and injecting 20 mL of THF and 2M, 8 mL of K2CO3 aqueous solution into the reaction vessel under nitrogen protection, refluxing overnight to obtain DMABZ-Br;

[0030] 2 mmol of DMABZ-Br, 3 mmol of 4-formylphenylboronic acid, and 0.02 equivalents of Pd(PPh3)4 (based on bromide) were placed in a reaction vessel, N2 was introduced, and under nitrogen protection, 20 mL of THF and 2 M, 8 mL of K2CO3 aqueous solution were injected into the reaction vessel. The mixture was refluxed overnight to obtain DMABZ-CHO.

[0031] 0.5 mmol of DMABZ-CHO and 0.7 mmol of 1,4-dimethylpyridine-1-iodide were dissolved in a THF / methanol mixture with a volume of 4 / 12. A few drops of piperidine were added to the mixture and the mixture was refluxed for 12 hours to obtain DMABZPy.

[0032] The present invention also provides the application of the aforementioned AIE-active photosensitizer in the preparation of photodynamic therapy drugs.

[0033] Compared with the prior art, the present invention has the following advantages:

[0034] By keeping the electron acceptor of charged pyridine unchanged, and using dimethylamine (DMA) and triphenylamine (TPA) as electron donors, and the fused rings of naphthalene (Np), anthracene (An), and benzothiadiazole (BZ) as π-bridges, we designed and synthesized a series of charged AIE-active photosensitizers by constructing the aforementioned electron fragments. Through molecular-level structural design and aggregation-level intermolecular interaction modulation, we were able to simultaneously improve their fluorescence and ROS generation efficiencies.

[0035] The photosensitizer itself forms self-aggregates or uses F127, DSPE-PEG 2000When preparing polymer nanoparticles with BSA, the electron donor rotor containing triphenylamine (TPA) enables TPA-substituted photosensitizers (TPABZPy) to exhibit stronger fluorescence and ROS efficiency. However, compared to TPA, dimethylamine (DMA) electron donors lack a benzene rotor, allowing DMA-substituted photosensitizers to improve fluorescence and ROS generation after pH stimulation. The charged nature and efficient ROS generation ensure that the photosensitizer exhibits targeted labeling of mitochondria and excellent PDT results at low dose concentrations. This invention provides a feasible molecular engineering approach to design responsive photosensitizers with enhanced fluorescence and ROS generation efficiency in acidic or aggregation-stimulated environments, showing promising potential in future smart PDTs. Attached Figure Description

[0036] The accompanying drawings, which are included to provide a further understanding of the invention and form part of this application, do not constitute an undue limitation of the invention. In the drawings:

[0037] Figure 1 This is a schematic diagram illustrating the structure of the photosensitizer of this invention;

[0038] Figure 2 This is the synthesis route diagram for DMANpPy;

[0039] Figure 3 It's DMANpPy. 1 H NMR spectrum;

[0040] Figure 4 It's DMANpPy. 13 C NMR spectrum;

[0041] Figure 5 This is the synthesis route diagram for TPANpPy;

[0042] Figure 6 It's TPANpPy. 1 HNMR spectrum;

[0043] Figure 7 It's TPANpPy. 13 C NMR spectrum;

[0044] Figure 8 This is the synthesis route diagram for DMAAnPy;

[0045] Figure 9 It's DMAAnPy. 1 H NMR spectrum;

[0046] Figure 10 It's DMAAnPy. 13 C NMR spectrum;

[0047] Figure 11 This is the synthesis route diagram for TPAAnPy;

[0048] Figure 12 It's TPAAnPy. 1 H NMR spectrum;

[0049] Figure 13 It's TPAAnPy. 13 C NMR spectrum;

[0050] Figure 14 This is the synthesis route diagram for DMABZPy;

[0051] Figure 15 It's DMABZPy. 1 H NMR spectrum;

[0052] Figure 16 It's DMABZPy. 13 C NMR spectrum;

[0053] Figure 17 This is the synthesis route diagram for TPABZPy;

[0054] Figure 18 It's TPABZPy. 1 H NMR spectrum;

[0055] Figure 19 It's TPABZPy. 13 C NMR spectrum;

[0056] Figure 20 This is a statistical graph of the absorption spectrum and photoluminescence (PL) spectrum of tetrahydrofuran solutions containing six photosensitizers;

[0057] Figure 21 This is a statistical chart of the maximum absorption peak and fluorescence peak of six photosensitizers in various solvents of different polarities (hexane, ethyl acetate, tetrahydrofuran, dichloromethane, and dimethylformamide);

[0058] Figure 22 It is a Stokes shift plot of 6 photosensitizers;

[0059] Figure 23 These are statistical graphs of the photoluminescence quantum yield (PLQY) of six photosensitizer films.

[0060] Figure 24 A is the PL spectrum of DMABZPy in DMSO / toluene mixtures with different toluene fractions;

[0061] Figure 24 B is a graph showing the change in the fluorescence intensity of the emitter of the photosensitizer in a dimethyl sulfoxide / toluene mixture;

[0062] Figure 25 The PL spectra of DMANpPy, DMAAnPy, TPANpPy, TPAAnPy, and TPABZPy in DMSO / toluene mixtures with different toluene fractions are shown.

[0063] Figure 26 These are the absorption spectra of six photosensitizers in aqueous solutions at different pH values.

[0064] Figure 27 These are the fluorescence spectra of DMABZPy and TPABZPy in solutions at different pH values;

[0065] Figure 28 These are fluorescence spectra of DMANpPy, DMAAnPy, TPANpPy, and TPAAnPy in aqueous solutions at different pH values.

[0066] Figure 29 The electrostatic potential surface diagram of the three DMA-substituted photosensitizers at the M06-2X / 6-31G(d,p) energy level is calculated using density functional theory.

[0067] Figure 30 These are fluorescence response graphs of six photosensitizers in different amino acid and BSA solutions.

[0068] Figure 31 This is the fluorescence spectrum of TPABZPy in aqueous solutions containing different amino acids and BSA biomolecules;

[0069] Figure 32 These are the absorption spectra of six photosensitizers in different amino acid and BSA solutions;

[0070] Figure 33 This is a statistical graph showing the fluorescence changes of six photosensitizers in aqueous solutions containing different amino acids and BSA.

[0071] Figure 34 This is a graph showing the changes in fluorescence intensity of TPABZPy in aqueous solutions containing different concentrations of BSA;

[0072] Figure 35 This is the PL spectrum of the H2DCF-DA probe in DMSO solutions containing different photosensitizers;

[0073] Figure 36 A is a graph showing the fluorescence intensity changes of the H2DCF-DA probe in DMSO solutions containing different photosensitizers;

[0074] Figure 36 B is a graph showing the fluorescence intensity changes of the H2DCF-DA probe in DMSO / H2O (v / v = 1:99) mixtures containing different photosensitizers;

[0075] Figure 37 This is the PL spectrum of the H2DCF-DA probe in a mixture of DMSO / H2O (v / v = 1:99) containing different photosensitizers;

[0076] Figure 38 This is the absorption spectrum of the ABDA probe in DMSO / water solution containing different photosensitizers, Rose Bengal (RB), and Chlorin e6 (Ce6);

[0077] Figure 39 This is a graph showing the changes in absorption intensity of the ABDA probe in DMSO / water solutions containing different photosensitizers, Rose Bengal (RB), and Chlorin e6 (Ce6).

[0078] Figure 40 This is a graph showing the fluorescence intensity changes of the H2DCF-DA probe in solutions containing DMANpPy / DMABZPy at different pH values.

[0079] Figure 41 This is the PL spectrum of the H2DCF-DA probe in solutions containing nanoparticles with different photosensitizers;

[0080] Figure 42 This is the absorption spectrum of the ABDA probe in solutions containing nanoparticles with different photosensitizers;

[0081] Figure 43 The left figure shows the fluorescence intensity changes of the H2DCF-DA probe in solutions containing nanoparticles with different photosensitizers;

[0082] Figure 43 The right figure shows the change in absorption intensity of the ABDA probe in solutions containing nanoparticles with different photosensitizers;

[0083] Figure 44 This is a schematic diagram illustrating the possible mechanism of the difference in ROS generation efficiency among different photosensitizer nanoparticles.

[0084] Figure 45 It consists of F127@TPABZPy nanoparticles and DSPE-PEG. 2000 PL spectra of @TPABZPy nanoparticles and BSA@TPABZPy nanoparticles;

[0085] Figure 46 This is a schematic diagram of theoretical calculations of the energy levels of the S1, T1, and T2 states of DMANpPy and the natural transition orbitals (NTOs).

[0086] Figure 47This is a schematic diagram of theoretical calculations of the energy levels of the S1, T1, and T2 states of TPANpPy and the natural transition orbitals (NTOs).

[0087] Figure 48 This is a schematic diagram of the theoretical calculation of the energy levels of the S1, T1, and T2 states of DMAAnPy and the natural transition orbitals (NTOs).

[0088] Figure 49 This is a schematic diagram of theoretical calculations of the energy levels of the S1, T1, and T2 states of TPAAnPy and the natural transition orbitals (NTOs).

[0089] Figure 50 This is a schematic diagram of the theoretical calculation of the energy levels of the S1, T1, and T2 states of DMABZPy and the natural transition orbitals (NTOs).

[0090] Figure 51 This is a schematic diagram of theoretical calculations of the energy levels of the S1, T1, and T2 states of TPABZPy and the natural transition orbitals (NTOs).

[0091] Figure 52 The optimal molecular conformation diagram of the photosensitizer based on the B3LYP / 6-31G(d,p) level DMA / TPA substitution is shown.

[0092] Figure 53 This is a CLSM image of HepG2 cells successively incubated with DMABZPy / TPABZPy and Mitotracker green. Ex = 488 nm, Em = 600–720 nm, laser concentration 5%; Mitotracker green concentration: 200 nm, Ex = 488 nm, Em = 500–550 nm. Scale bar = 15 μm;

[0093] Figure 54 These are CLSM images of HepG2 cells irradiated at 543 nm with 10% laser power at different times after being incubated with DMABZPy / TPABZPy and H2DCF-DA probes. Scale bar = 100 μm.

[0094] Figure 55 This is a statistical chart showing the dark toxicity and in vitro PDT results of DMABZPy and TPABZPy.

[0095] (A)DMABZPy, (B)TPABZPy;

[0096] Figure 56 The figure shows the survival rate of HepG2 cells after incubation with DMABZPy / TPABZPy under light and no light, using fluorescein diacetate (FDA) and propidium iodide (PI) as fluorescent probes.

[0097] Figure 57 These are fluorescence images of DMABZPy and HepG2 cells after incubation at different pH levels.

[0098] Figure 58 This is a schematic diagram of the treatment process in the 4T1 tumor-bearing mouse experimental group;

[0099] Figure 59 It includes statistical graphs of body weight and tumor size of mice in different groups during the treatment process, as well as experimental graphs of mouse sacrifice and tumor growth status;

[0100] Figure 60 This is an experimental diagram showing the H&E staining analysis of tumor tissues from different groups 14 days after treatment.

[0101] Figure 61 This is an experimental diagram showing the H&E staining analysis of the heart, liver, spleen, lungs, and kidneys in different groups 14 days after treatment;

[0102] Figure 62 This is a statistical chart of hematological data of mice in different groups after 14 days of treatment. Detailed Implementation

[0103] The present invention will now be described in detail with reference to the accompanying drawings and specific embodiments. The illustrative embodiments and descriptions of the present invention are used to explain the present invention, but are not intended to limit the present invention.

[0104] Unless otherwise specified in this manual, all reagents are commercially available reagents, and the experimental methods are conventional methods in this field.

[0105] Example 1: Synthesis of DMANpPy

[0106] Preparation of DMANp-CHO

[0107] 1,4-Dibromonaphthalene (5 mmol, 1.42 g), 4-(dimethylamino)phenylboronic acid pinacol ester (6 mmol, 1.23 g), and Pd(PPh3)4 (0.02 equivalent, 116 mg as the bromine-substituted product) were placed in a two-necked flask. Under nitrogen protection, THF (20 mL) and a 2 M, 8 mL aqueous solution of K2CO3 were injected into the flask. The mixture was refluxed overnight. As the temperature decreased, the mixture was extracted three times with DCM, and column chromatography yielded a white powder, DMNp-Br (1.03 g), in 50% yield.

[0108] DMANp-Br (2 mmol, 650 mg), 4-formylphenylboronic acid (3 mmol, 450 mg), and Pd(PPh3)4 (0.02 equivalent, 46 mg as the bromine-substituted product) were placed in a two-necked flask. Under nitrogen protection, THF (20 mL) and a 2 M, 8 mL aqueous solution of K2CO3 were injected into the flask. The mixture was refluxed overnight. When the temperature decreased, the mixture was extracted three times with DCM, and column chromatography yielded a yellow powder, DMANp-CHO (582 mg), in 83% yield. 1 H NMR (500MHz, d-DMSO) δ = 8.92 (s, 1H), 8.07 (d, 2H), 7.99 (m, 1H), 7.80 (m, 1H ),7.75(d,2H),7.51-7.45(m,4H),7.35(d,2H),6.89(d,2H),2.97(s,6H).

[0109] Preparation of DMANpPy

[0110] DMANp-CHO (175 mg, 0.5 mmol) and 1,4-dimethylpyridine-1-iodide (168 mg, 0.7 mmol) were dissolved in a THF / methanol mixture (V / V = 4 / 12). A few drops of piperidine were added to the mixture and refluxed for 12 hours. After cooling, the solution was evaporated. The mixture was extracted three times with DCM, the DCM was evaporated, and the resulting product was placed in a large volume of petroleum ether and refluxed overnight. Finally, a red powder (185 mg) was obtained by column chromatography in 65% yield. 1 H NMR(500MHz,d-DMSO)δ=8.89(d,2H),8.27(d,2H),8.14(d,2H),7.98(m,1H),7.92-7.86(m,3H ),7.64-7.59(m,3H),7.51-7.49(m,4H),7.35(d,2H),6.89(d,2H),4.26(s,3H),2.97(s,6H). 13 C NMR (126MHz, DMSO) δ150.29,145.66.132.05,131.61,131.10,130.91,128.77,127.17,126.77,126.64,126.51,124.09,112.78,47.43.

[0111] 1,4-Dimethylpyridin-1-ium iodide has been reported in existing technologies, such as "Molecular Engineering to Boost AIE-Active FreeRadical Photogenerators and Enable High-Performance Photodynamic Therapyunder Hypoxia".

[0112] The synthetic route of DMANpPy is as follows: Figure 2 As shown, its 1 H NMR spectrum as shown Figure 3 As shown, 13 The C NMR spectrum is as follows Figure 4 As shown.

[0113] Example 2: Synthesis of TPANpPy

[0114] Preparation of TPANp-Br

[0115] 1,4-Dibromonaphthalene (5 mmol, 1.42 g), triphenylamine boric acid (6 mmol, 1.73 g), and Pd(PPh3)4 (0.02 equivalent, 116 mg as a bromine-substituted product) were placed in a two-necked flask. Under nitrogen protection, THF (20 mL) and a 2 M, 8 mL aqueous solution of K2CO3 were injected into the flask. The mixture was refluxed overnight. When the temperature decreased, the mixture was extracted three times with DCM, and column chromatography yielded a white powder, TPANp-Br (1.19 g), in 53% yield. 1 H NMR (500MHz, d-DMSO) δ = 8.25 (d, 11H), 7.97 (d, 2H), 7.75 (t, 2H), 7.66-7.40 (m, 7H), 7.38-7.12 (m, 8H).

[0116] Preparation of TPANp-CHO

[0117] TPANp-Br (2 mmol, 898 mg), 4-formylphenylboronic acid (3 mmol, 450 mg), and Pd(PPh3)4 (0.02 equivalent, 46 mg as the bromine-substituted product) were placed in a two-necked flask. Under nitrogen protection, THF (20 mL) and a 2 M, 8 mL aqueous solution of K2CO3 were injected into the flask. The mixture was refluxed overnight. When the temperature decreased, the mixture was extracted three times with DCM, and column chromatography yielded a yellow powder, TPANp-CHO (817 mg), in 86% yield. 1H NMR (500MHz, d-DMSO) δ = 10.14 (s, 1H), 8.11 (d, 4H), 7.79 (m, 3H), 7.47-7.16 (m, 17H.

[0118] Preparation of TPANpPy

[0119] TPANp-CHO (238 mg, 0.5 mmol) and 1,4-dimethylpyridine-1-iodide (168 mg, 0.7 mmol) were dissolved in a THF / methanol mixture (V / V = 4 / 12). A few drops of piperidine were added to the mixture and refluxed for 12 hours. After cooling, the solution was evaporated. The mixture was extracted three times with DCM, the DCM was evaporated, and the resulting product was placed in a large volume of petroleum ether and refluxed overnight. Finally, a red powder (235 mg) was given, with a yield of 68%. 1 H NMR (500MHz, d-DMSO) δ = 8.91 (d, 2H), 8.29 (d, 2H), 8.16 (d, 2H), 8.00-7.87 (m, 4H), 7.65-7.6 1(m,2H),7.56-7.51(m,4H),7.43(d,2H),7.37-7.32(m,5H),7.12-7.06(m,8H),4.26(s,3H). 13 C NMR (126MHz, DMSO) δ152.90,147.55,147.21,145.68,142.48,140.66,139.70,138.56,134.88,134.09,131.81,1 31.56,131.34,131.08,130.17,128.79,127.12,126.94,126.89,126.83,124.83,124.10,123.86,123.08,47.40.

[0120] The synthetic route of TPANpPy is as follows: Figure 5 As shown, its 1 H NMR spectrum as shown Figure 6 As shown, 13 The C NMR spectrum is as follows Figure 7 As shown.

[0121] Example 3: Synthesis of DMAAnPy

[0122] Preparation of BrAn CHO

[0123] 9,10-Dibromoanthracene (5 mmol, 1.67 g), 4-formylphenylboronic acid (6 mmol, 900 mg), and Pd(PPh3)4 (0.02 equivalent, 116 mg as the bromine-substituted product) were placed in a two-necked flask. Under nitrogen protection, THF (20 mL) and a 2 M, 8 mL aqueous solution of K2CO3 were injected into the flask. The mixture was refluxed overnight. As the temperature decreased, the mixture was extracted three times with DCM, and column chromatography yielded a white powder BrAn-CHO (954 mg), in 53% yield. 1 H NMR (500MHz, d-DMSO) δ = 10.18 (s, 1H), 8.53 (d, 2H), 8.17 (d, 2H), 7.74 (t, 2H), 7.66 (d, 2H), 7.51-7.47 (m, 4H).

[0124] Preparation of DMAAn-CHO

[0125] BrAn CHO (2 mmol, 720 mg), 4-(dimethylamino)phenylboronic acid pinacol ester (3 mmol, 740 mg), and Pd(PPh3)4 (0.02 equivalent, 43 mg as the bromine-substituted product) were placed in a two-necked flask. Under nitrogen protection, THF (20 mL) and a 2M K2CO3 aqueous solution (8 mL) were injected into the flask. The mixture was refluxed overnight. When the temperature decreased, the mixture was extracted three times with DCM, and column chromatography yielded a white powder DMAAn-CHO (625 mg), in 78% yield. 1 H NMR (500MHz, d-DMSO) δ = 10.19 (s, 1H), 8.16 (d, 2H), 7.70 (m, 4H), 7.45-7.40 (m, 6H), 7.24 (d, 2H), 6.98 (d, 2H), 3.03 (s, 6H).

[0126] Preparation of DMAAnPy

[0127] DMAAn CHO (200 mg, 0.5 mmol) and 1,4-dimethylpyridine-1-iodide (168 mg, 0.7 mmol) were dissolved in a THF / methanol mixture (V / V = 4 / 12). A few drops of piperidine were added to the mixture and refluxed for 12 hours. After cooling, the solution was evaporated. The mixture was extracted three times with DCM, the DCM was evaporated, and the resulting product was placed in a large volume of petroleum ether and refluxed overnight. Finally, a red powder (126 mg) was given, with a yield of 63%. 1H NMR(500MHz,d-DMSO)δ=8.98(d,2H),8.29(d,2H),8.20(d,1H),8.02(d,2H),7.75-7.65 (m,3H),7.59(t,4H),7.41(t,4H),7.26(d,2H),6.99(d,2H),4.26(s,3H),3.03(s,6H). 13 C NMR (126MHz, DMSO) δ152.93,151.45,146.05,141.44,140.95,138.72,136.09,135.53,135.22,134.50,132.3 7,132.01,130.21,129.65,128.84,127.44,126.56,126.12,125.67,125.37,124.29,124.15,112.77,47.47.

[0128] The synthetic route of DMAAnPy is as follows: Figure 8 As shown, its 1 H NMR spectrum as shown Figure 9 As shown, 13 The C NMR spectrum is as follows Figure 10 As shown.

[0129] Example 4: Synthesis of TPAAnPy

[0130] Preparation of TPAAn-CHO

[0131] BrAn CHO (2 mmol, 720 mg), triphenylamine boric acid (3 mmol, 867 mg), and Pd(PPh3)4 (0.02 equivalent, 43 mg as the bromine-substituted product) were placed in a two-necked flask. N2 was pumped in and purged three times, and THF (20 mL) and K2CO3 aqueous solution (2 M, 8 mL) were injected into the flask. The mixture was refluxed overnight. As the temperature decreased, the mixture was extracted three times with DCM, and a white powder TPAAn-CHO (625 mg) was obtained by column chromatography in 81% yield. 1 H NMR (500MHz, d-DMSO) δ = 10.19 (s, 1H), 8.18 (d, 2H), 7.75-7.68 (m, 4H), 7.50-7.31 (m, 12H), 7.20-7.08 (m, 8H).

[0132] Preparation of TPAAnPy

[0133] TPAAn-CHO (263 mg, 0.5 mmol) and 1,4-dimethylpyridine-1-iodide (168 mg, 0.7 mmol) were dissolved in a THF / methanol mixture (V / V = 4 / 12). A few drops of piperidine were added to the mixture and refluxed for 12 hours. After cooling, the solution was evaporated. The mixture was extracted three times with DCM, the DCM was evaporated, and the resulting product was placed in a large volume of petroleum ether and refluxed overnight. Finally, a green powder (241 mg) was given, with a yield of 65%. 1 H NMR(500MHz,d-DMSO)δ=8.94(d,2H),8.23(d,1H),8.03(d,2H),7.75(t,3H ),7.75(d,3H),7.45-7.32(m,9H),7.21(d,7H),7.10(t,3H),4.29(s,3H). 13 C NMR (126MHz, DMSO) δ151.84,146.52,146.22,144.65,139.84,139.65,136.21,135.02,134.12,131.34,131.23,130.8 6,129.14,128.83,128.51,127.78,126.09,125.58,125.15,124.97,123.90,123.27,123.08,122.87,121.79,46.35.

[0134] The synthetic route of TPAAnPy is as follows: Figure 11 As shown, its 1 H NMR spectrum as shown Figure 12 As shown, 13 The C NMR spectrum is as follows Figure 13 As shown.

[0135] Example 5: Synthesis of DMABZPy

[0136] Preparation of DMABZ-Br

[0137] 4,7-Dibromo-2,1,3-benzothiadiazole (5 mmol, 1.46 g), pinacol ester of 4-(dimethylamino)phenylboronic acid (6 mmol, 1.45 g), and Pd(PPh3)4 (0.02 equivalent, 116 mg as brominated product) were placed in a two-necked flask. Under nitrogen protection, THF (20 mL) and a 2 M, 8 mL aqueous solution of K2CO3 were injected into the flask. The mixture was refluxed overnight. As the temperature decreased, the mixture was extracted three times with DCM, and column chromatography yielded a white powder DMABZ-Br (963 mg), in 58% yield. 1H NMR (500MHz, d-DMSO) δ = 8.02 (d, 1H), 7.87 (d, 2H), 7.65 (d, 1H), 6.84 (d, 2H), 2.96 (s, 6H).

[0138] Preparation of DMABZ-CHO

[0139] DMABZ-Br (2 mmol, 666 mg), 4-formylphenylboronic acid (3 mmol, 450 mg), and Pd(PPh3)4 (0.02 equivalent, 46 mg as bromide) were placed in a two-necked flask. N2 was pumped in and purged three times. Under nitrogen protection, THF (20 mL) and K2CO3 aqueous solution (2 M, 8 mL) were injected into the flask. The mixture was refluxed overnight. As the temperature decreased, the mixture was extracted three times with DCM, and column chromatography yielded a yellow powder DMABZ-CHO (567 mg), with a yield of 79%. 1 H NMR (500MHz, d-DMSO) δ = 10.07 (s, 1H), 8.23 ​​(d, 2H), 8.05-7.94 (m, 5H), 7.87 (d, 1H), 6.86 (d, 2H), 2.98 (s, 6H).

[0140] Preparation of DMABZPy

[0141] DMABZ-CHO (180 mg, 0.5 mmol) and 1,4-dimethylpyridine-1-iodide (168 mg, 0.7 mmol) were dissolved in a THF / methanol mixture (V / V = 4 / 12). A few drops of piperidine were added to the mixture and refluxed for 12 hours. After cooling, the solution was evaporated. The mixture was extracted three times with DCM, the DCM was evaporated, and the resulting product was placed in a large volume of petroleum ether and refluxed overnight. Finally, a red powder (210 mg) was given, with a yield of 73%. 1 H NMR (500MHz, d-DMSO) δ = 8.86 (s, 2H), 8.24 (s, 2H), 8.17 (d, 2H), 8.10 (d, 1H), 8.00-7 .95(m,3H),7.91-7.86(m,3H),7.61(d,1H),6.88(d,2H),4.25(s,3H),2.99(s,6H). 13 C NMR (126MHz, DMSO) δ153.96,152.86,150.91,145.62,140.57,139.33,135.19,133.5 9,130.38,130.00,129.73,129.38,128.79,126.42,124.45,124.07,112.54,47.42.

[0142] The synthetic route of DMABZPy is as follows: Figure 14 As shown, its 1 H NMR spectrum as shown Figure 15 As shown, 13 The C NMR spectrum is as follows Figure 16 As shown.

[0143] Example 6: Synthesis of TPABZPy

[0144] Preparation of BrBZ-CHO

[0145] 4,7-Dibromo-2,1,3-benzothiadiazole (5 mmol, 1.46 g) and 4-formylphenylboronic acid (6 mmol, 900 mg), Pd(PPh3)4 (0.02 equivalent, 116 mg as brominated product) were placed in a two-necked flask. Under nitrogen protection, THF (20 mL) and a 2 M, 8 mL aqueous solution of K2CO3 were injected into the flask. The mixture was refluxed overnight. As the temperature decreased, the mixture was extracted three times with DCM, and column chromatography yielded a white powder BrBZ-CHO (738 mg), in 61% yield. 1 H NMR (500MHz, d-DMSO) δ = 10.08 (s, 1H), 8.18 (t, 3H), 8.06 (d, 2H), 7.89 (d, 1H).

[0146] Preparation of TPABZ-CHO

[0147] BrBZ-CHO (2 mmol, 484 mg), triphenylamine boric acid (3 mmol, 867 mg), and Pd(PPh3)4 (0.02 equivalent, 46 mg as brominated product) were placed in a two-necked flask. After pumping and purging with N2 three times, under nitrogen protection, THF (20 mL) and K2CO3 aqueous solution (2 M, 8 mL) were injected into the flask. The reaction mixture was refluxed overnight. As the temperature decreased, the mixture was extracted three times with DCM, and column chromatography yielded a yellow powder TPABZ-CHO (734 mg), with a yield of 76%. 1 H NMR (500MHz, d-D2Cl2)δ=10.10(s,1H),8.20(d,2H),8.04(d,2H),7.93-7.87(m,3H),7.82(d,1H),7.34(t,4H),7.20-7.17(m,6H),7.11(t,2H).

[0148] Preparation of TPABZPy

[0149] TPABZ-CHO (242 mg, 0.5 mmol) and 1,4-dimethylpyridine-1-iodide (168 mg, 0.7 mmol) were dissolved in a THF / methanol mixture (V / V = 4 / 12). A few drops of piperidine were added to the mixture and refluxed for 12 hours. After cooling, the solution was evaporated. The mixture was extracted three times with DCM, the DCM was evaporated, and the resulting product was placed in a large volume of petroleum ether and refluxed overnight. Finally, an orange powder (287 mg) was given, with a yield of 82%. 1 H NMR (500MHz, d-DMSO) δ = 8.90 (d, 2H), 8.21 (d, 2H), 8.13-8.05 (m, 2H), 8.00-8.05 (m, 5H), 7.65 (d, 1H), 7.37 (t, 4H), 7.14 (m, 8H), 4.28 (s, 3H). 13 C NMR (126MHz, DMSO) δ153.86,153.78,152.83,148.10,147.32,145.65,140.51,139.10,135.42,132.8 2,130.71,130.20,130.14,129.22,128.61,127.83,125.05,124.21,124.14,124.10,122.66,47.44.

[0150] The synthetic route of TPABZPy is as follows: Figure 17 As shown, its 1 H NMR spectrum as shown Figure 18 As shown, 13 The C NMR spectrum is as follows Figure 19 As shown.

[0151] Example 7

[0152] This embodiment characterizes the photophysical properties of the six photosensitizers prepared in Examples 1-6.

[0153] Six photosensitizers were dissolved in THF at a concentration of 10%. -5 M, unless otherwise specified below, the concentration of the photosensitizer dissolved in the solvent is 10. -5 M. All six photosensitizers exhibit good solubility in THF solvent. The absorption spectra of tetrahydrofuran solutions of the six photosensitizers are as follows: Figure 20As shown in Figure A, the maximum absorption peaks of DMABZPy and DMAAnPy are located at 356 nm, shorter than those of DMABZPy, which has a maximum absorption peak at 468 nm. This is attributed to the enhanced electron-withdrawing ability of the acceptor fragment, which improves the intramolecular charge transfer (ICT) effect. Since the BZ unit is a typical electron acceptor, it has wide applications in optoelectronic devices and biomedicine. When the DMA unit is replaced by the TPA unit, TPABZPy exhibits a longer maximum absorption peak than TPANpPy and TPAAnPy. Comparing these two types of photosensitizers, it can be found that the maximum absorption peaks of TPA-substituted photosensitizers are shorter than those of the corresponding DMA-substituted photosensitizers. This may be due to the stronger electron-donating ability of DMA compared to TPA.

[0154] Photoluminescence (PL) spectra of tetrahydrofuran solutions containing six photosensitizers are as follows: Figure 20 As shown in Figure B, the illustration shows a photograph of the photosensitizer solution under a UV lamp. The trend of the maximum fluorescence peak is similar to that of the absorption spectrum. The maximum fluorescence peaks of the three DMA-substituted photosensitizers are longer than those of the corresponding TPA-substituted photosensitizers. This helps the DMA-substituted photosensitizers to obtain a stronger ICT effect in THF solution than the TPA-substituted photosensitizers.

[0155] Solvent effects can be used to compare the ICT effects of photosensitizers and to identify their sensitivity to environmental polarity. For example... Figure 21 As shown, their maximum absorption peaks remain almost unchanged in various solvents of different polarities (hexane, ethyl acetate, tetrahydrofuran, dichloromethane, and dimethylformamide), indicating that their ground-state optical properties are unaffected by environmental polarity. Conversely, their maximum fluorescence peaks exhibit a significant redshift with increasing environmental polarity, suggesting a typical ICT effect in their excited states.

[0156] Calculate Stokes displacement to compare their ICT strength, such as Figure 22 As shown, in various solvents, BZ-based photosensitizers exhibit larger Stokes shifts than other photosensitizers, indicating a stronger ICT effect. An-based photosensitizers, due to their small Stokes shifts from low-polarity to high-polarity solvents, show a weaker ICT effect. Notably, both BZ-based photosensitizers have larger Stokes shifts in the same solvent than the Np / An-based photosensitizer, supporting the conclusion that BZ-based photosensitizers have a stronger ICT effect than Np / An-based photosensitizers.

[0157] Six photosensitizers were prepared into thin films, and their photoluminescence (PL) spectra were measured. The results are as follows: Figure 23 As shown in the left figure, with Figure 20Compared to the PL spectrum of B, the maximum fluorescence peak of each photosensitizer begins to redshift in the aggregated state, and the BZ-based photosensitizer emits deep red fluorescence, which is helpful for the practical application of fluorescence bioimaging.

[0158] Measurements of photoluminescent quantum yield (PLQY) revealed that, as Figure 23 As shown in the right figure, the inset is a photograph of the photosensitizer powder under a UV lamp. The DMA-substituted photosensitizer has almost no fluorescence in powder form, but the TPA-substituted photosensitizer has a higher PLQY than the corresponding DMA-substituted photosensitizer. TPA mainly helps the rotor-type electron donor to endow the photosensitizer with better AIE properties, which is very much in line with our initial molecular design ideal.

[0159] Example 8

[0160] This embodiment further characterized the stimulus-responsive fluorescence changes of six photosensitizers. First, since the charged photosensitizers have poor solubility in toluene, the different aggregation degrees of these photosensitizers can be adjusted by mixing different fractions of toluene with dimethyl sulfoxide. Therefore, typical AIE measurements were performed, such as... Figure 24 As shown in Figure A, taking DMABZPy as an example, it dissolves well in DMSO solvent. Due to strong polarity and vigorous molecular motion quenching emission, it exhibits very weak fluorescence. When the toluene fraction in the DMSO solvent increases, DMABZPy aggregates form, and the fluorescence intensity begins to increase, indicating that aggregation enhances fluorescence. Other photosensitizers also exhibit typical AIE properties, such as... Figure 24 As shown in B, 25 Figure 25 Among (A)DMANpPy, (B)DMAAnPy, (C)TPANpPy, (D)TPAAnPy, and (E)TPABZPy, a blue shift can be observed from single molecules to aggregates. The enhanced fluorescence and emission blue shift contribute to the synergistic effect of the AIE and TICT (Twisted Intramolecular Charge Transfer) mechanisms.

[0161] Besides forming aggregates, pH can also induce changes in the optical properties of some DMA-substituted photosensitizers, but has no effect on TPA-substituted photosensitizers. Absorption and fluorescence spectra were measured by dissolving the six photosensitizers in aqueous solutions at different pH values ​​(7.4, 6.8, 5.8, and 4.5).

[0162] The first difference between DMA-substituted and TPA-substituted photosensitizers is their absorption spectra in aqueous solutions at different pH values, such as... Figure 26As shown in Figure DF, (D) TPANpPy, (E) TPAAnPy, and (F) TPABZPy, an acidic environment did not cause any change in the absorption spectra of these three TPA-substituted photosensitizers, preliminarily proving that they do not react in acidic solutions and have better stability. The difference is that, as... Figure 26 As shown in AC, the absorption spectra of three DMA-substituted photosensitizers—(A) DMANpPy, (B) DMAAnPy, and (C) DMABZPy—exhibit significant differences in acidic and neutral solutions. Taking DMAAnPy as an example, the absorption intensity expands from neutral to acidic environments. However, for DMANpPy and DMABZPy, the absorption peaks at 454 nm and 437 nm disappear under acidic conditions, which may be attributed to the weakening of the ICT effect after protonation of the DMA group.

[0163] Fluorescence spectra of six photosensitizers in solutions with different pH values ​​are as follows: Figure 27-28 As shown, Figure 27 The left image shows DMABZPy, and the inset image shows the fluorescence spectrum of the DMABZPy solution. Figure 27 The right figure shows TPABZPy, and the inset shows the fluorescence spectrum of the TPABZPy solution. Figure 28 The fluorescence spectra of (A) DMANpPy, (B) DMAAnPy, (C) TPANpPy, and (D) TPAAnPy in aqueous solutions at different pH values ​​show that the DMA-substituted photosensitizers exhibit a significant pH response, with DMANpPy and DMABZPy showing enhanced fluorescence in acidic solutions. However, the fluorescence of the TPA-substituted photosensitizers shows almost no change in acidic solutions, indicating that the TPA units are not protonated.

[0164] like Figure 29 As shown, surface electrostatic potential (EPS) maps of the three DMA-substituted photosensitizers at the M06-2X / 6-31G(d,p) energy level were calculated using density functional theory to demonstrate possible protonation sites. It can be noted that charged pyridine units have larger EPS values, which rules out the possibility of protonated pyridine formation. Therefore, the protonation reaction may occur at the DMA unit sites, as their EPS values ​​are smaller.

[0165] Various amino acids and BSA were used to interact with all photosensitizers. The response characteristics of the photosensitizers to amino acids and BSA were clearly investigated by measuring absorption and fluorescence spectra. Six photosensitizers were added to solutions of a: DL-phenylalanine, b: L-proline, c: L-cysteine, d: L-alanine, e: L-serine, F: L-lysine, g: L-methionine, h: valine, i: L-arginine, j: d-cysteine, and k: BSA.

[0166] like Figure 30As shown, the photosensitizer concentration is 5 × 10⁻⁶. -4 M, amino acid concentration is 5×10 -3 M, BSA concentration is 0.5 mg / mL; it can be seen that only TPABZPy has a specific fluorescent response to BSA.

[0167] The fluorescence spectra of TPABZPy in aqueous solutions containing different amino acids and BSA biomolecules are as follows: Figure 31 As shown, the TPABZPy concentration is 2.5 × 10⁻⁶. -2 mM, amino acid concentration 0.25mM, BSA concentration: 2.5×10 -2 At a concentration of mg / mL, TPABZPy exhibits enhanced fluorescence intensity and a red shift upon interaction with BSA, but various amino acids do not trigger this fluorescence enhancement. For other photosensitizers besides TPABZPy, neither various amino acids nor BSA induce any change in fluorescence.

[0168] like Figure 32 As shown, (A) DMANpPy, (B) DMAAnPy, (C) DMABZPy, (D) TPANpPy, (E) TPAAnPy, (F) TPABZPy, with a photosensitizer concentration of 2.5 × 10⁻⁶. -5 M, amino acid concentration 2.5 × 10 -4 M, BSA concentration 2.5 × 10 - 2 At mg / mL, the maximum absorption of the four Np / An-based photosensitizers did not change significantly. DMABZPy red-shifted by 46 nm when interacting with BSA, and TPABZPy red-shifted by 16 nm when interacting with BSA, demonstrating that BZ-based photosensitizers readily interact with BSA.

[0169] like Figure 33 As shown, the three TPA-substituted photosensitizers exhibited enhanced fluorescence intensity after interacting with BSA, especially for TPABZPy, where the fluorescence intensity increased by more than 40-fold. However, the DMA-substituted photosensitizers showed almost no response to BSA.

[0170] The increased fluorescence intensity may contribute to electrostatic interactions, as BSA is negative while TPA-based photosensitizers are positive. This restricts the movement of TPA-substituted photosensitizers within the BSA matrix, inducing their AIE effect. Due to the lack of a benzene ring rotor, DMA-substituted photosensitizers are difficult to trigger AIE properties in BSA solutions. The changes in fluorescence intensity of TPABZPy in aqueous solutions containing different concentrations (0, 0.15, 0.3, 0.45, 0.9, 1.7, 3.35, 6.7, 12.5, 25, 50, 100 μg / mL) of BSA were measured at a concentration of 5 μM. Figure 34A good linear relationship between fluorescence intensity and BSA concentration was shown. The higher the BSA concentration, the greater the fluorescence intensity of TPABZPy. The limit of detection (LOD) was calculated to be 5.88 μg / mL. Inset: Fluorescence spectra of TPABZPy in BSA solutions of different concentrations.

[0171] Example 9

[0172] Different stimulus interactions can also enhance the ROS generation efficiency of photosensitizers. For example, the first stimulatory factor triggering "aggregation" by the inherent hydrophobicity of these photosensitizers can significantly improve ROS generation efficiency. Six different photosensitizers were dissolved separately in DMSO solutions containing the H2DCF-DA probe, with photosensitizer concentrations of 1 μM and H2DCF-DA concentrations of 10 μM. The six photosensitizers dissolved well in DMSO. Figure 35 As shown, the fluorescence intensity of (A)DMANpPy, (B)DMAAnPy, (C)DMABZPy, (D)TPANpPy, (E)TPAAnPy, (F)TPABZPy, and H2DCF-DA probes did not increase after white light irradiation. The fluorescence intensity changes are as follows: Figure 36 As shown in Figure A, it can be seen that the six photosensitizers remained in a single-molecule state and no ROS was generated.

[0173] Six different photosensitizers, Rose Bengal (RB), and Chlorin e6 (Ce6) were dissolved in DMSO / water solutions containing the H2DCF-DA probe, respectively. The DMSO / H2O ratio was 1:99, the photosensitizer concentration was 1 μM, and the H2DCF-DA concentration was 10 μM. The photoluminescence (PL) spectra are shown below. Figure 37 As shown, (A) pure H2DCF-DA, (B) RB, (C) Ce6, (D) DMANpPy, (E) DMAAnPy, (F) DMABZPy, (G) TPANpPy, (H) TPAAnPy, and (I) TPABZPy, due to their hydrophobicity, form obvious aggregates, resulting in significantly enhanced fluorescence and improved ROS generation efficiency. The fluorescence intensity changes of the H2DCF-DA probe are shown in the figure. Figure 36 As shown in Figure B, it exhibits typical aggregation-induced emission and ROS generation behavior.

[0174] Six different photosensitizers, Rose Bengal (RB), and Chlorin e6 (Ce6) were dissolved in DMSO / H2O aqueous solutions containing ABDA probes, with a DMSO / H2O ratio of 1:99, a photosensitizer concentration of 4 μM, and an ABDA probe concentration of 40 μM. Interestingly, as... Figures 38-39As shown, (A)RB, (B)Ce6, (C)DMANpPy, (D)DMAAnPy, (E)DMABZPy, (F)TPANpPy, (G)TPAAnPy, (H)TPABZPy. From the decrease rate and magnitude of fluorescence intensity reduction of the ABDA probe, it can be seen that the TPA-substituted photosensitizer has a higher ROS generation efficiency than the DMA-substituted photosensitizer. The ABDA probe demonstrates that the ROS generated by both TPA-substituted and DMA-substituted photosensitizers belongs to singlet oxygen (…). 1 O2), and because their absorption intensity decreases rapidly within a certain period of time, 1 O2 generation efficiency is far superior to that of commercial photosensitizers such as Bengal rose red (RB) and dihydroporphyrin e6 (Ce6).

[0175] DMABZPy and DMAB2Py were dissolved in solutions containing H2DCF-DA probe at different pH values ​​(5.8, 7.4), with photosensitizer concentration of 1 μM and H2DCF-DA probe concentration of 10 μM. The fluorescence intensity changes of the H2DCF-DA probe are shown below. Figure 40 As shown, the ROS production efficiency of DMANpPy and DMABZPy slightly increased from neutral solution to weakly acidic environment, indicating that acid promotes ROS production.

[0176] TPABZPy was encapsulated using different amphiphilic polymers and BSA biomacromolecules to investigate the effect of aggregates formed by different methods on ROS generation efficiency. The procedure is as follows:

[0177] Preparation of DSPE-PEG 2000 @TPABZPy Nanoparticles: 2mg DSPE-PEG 2000 Dissolve 1 mg of TPABZPy thoroughly in 1 mL of THF. Add the solution to 9 mL of distilled water and sonicate for 10 minutes. Stir the resulting solution slowly for 48 hours until THF is removed. A clear, orange aqueous solution is obtained.

[0178] Preparation of F127@TPABZPy nanoparticles: 2 mg F127 (an addition polymer of polypropylene glycol and ethylene oxide (polyether)) and 1 mg TPABZPy were thoroughly dissolved in 1 mL THF. The solution was then placed in 9 mL of distilled water and sonicated for 10 minutes. The resulting solution was slowly stirred for 48 hours until the THF was removed. A clear orange aqueous solution was obtained.

[0179] Preparation of BSA@TPABZPy nanoparticles: Dissolve 1 mg TPABZPy and 2 mg BSA thoroughly in 1 mL THF and 9 mL distilled water, respectively. Then mix the two solutions and stir slowly for 48 hours until THF is removed. A clear orange aqueous solution is obtained.

[0180] TPABZPy, F127@TPABZPy nanoparticles, and DSPE-PEG were used. 2000 @TPABZPy nanoparticles and BSA@TPABZPy nanoparticles dissolved in a solution containing H2DCF-DA probe, the PL spectrum of the H2DCF-DA probe is as follows. Figure 41 As shown, (A) TPABZPy, (B) F127@TPABZPy nanoparticles, and (C) DSPE-PEG 2000 @TPABZPy nanoparticles and (D)BSA@TPABZPy nanoparticles. The H2DCF-DA probe showed almost no change in fluorescence intensity in solutions containing TPABZPy and F127@TPABZPy nanoparticles. The H2DCF-DA probe showed little change in fluorescence intensity in solutions containing DSPE-PEG. 2000 The fluorescence intensity of @TPABZPy nanoparticles and BSA@TPABZPy fluorescent nanoparticles in solution is initially very weak, gradually increasing over time. The change in fluorescence intensity of the H2DCF-DA probe is as follows: Figure 43 The left figure shows (Aggregate represents TPABZPy hydrophobic aggregation).

[0181] from Figure 43 The left figure shows that after TPABZPy is coated with polymer, the fluorescence enhancement factor of the H2DCF-DA probe under light irradiation is higher than that of the solution containing pure photosensitizer, and the ROS generation efficiency is significantly improved. This indicates that polymer coating can improve the ability of photosensitizers to generate reactive oxygen species. However, the ROS generation in the solutions containing TPABZPy and F127@TPABZPy nanoparticles is explosive, reaching maximum efficiency within a short time. In contrast, the ROS generation in the solution containing DSPE-PEG is... 2000 The ROS generation efficiency of solutions containing @TPABZPy nanoparticles and BSA@TPABZPy nanoparticles increases slowly.

[0182] TPABZPy, F127@TPABZPy nanoparticles, and DSPE-PEG were used. 2000 @TPABZPy nanoparticles and BSA@TPABZPy nanoparticles were dissolved in a solution containing ABDA probes. The absorption spectra of the three types of coated TPABZPy solutions are as follows: Figure 42 As shown: (A) F127@TPABZPy nanoparticles, (B) DSPE-PEG 2000@TPABZPy nanoparticles, (C)BSA@TPABZPy nanoparticles, the ABDA probe absorption intensity is initially strong, but gradually weakens over time. The change in ABDA probe absorption intensity is as follows: Figure 43 As shown in the right figure, the faster the absorption intensity decreases, the stronger the singlet oxygen production. Figure 43 As shown in the right figure, the solution containing TPABZPy showed the fastest decline, followed by the solution containing F127@TPABZPy nanoparticles, while the others were roughly equivalent.

[0183] This paper proposes possible mechanisms to explain the differences in ROS generation efficiency among TPABZPy, F127@TPABZPy nanoparticles, DSPE-PEG2000@TPABZPy nanoparticles, and BSA@TPABZPy nanoparticles. For example... Figure 44 As shown, due to its hydrophobic nature, TPABZPy self-aggregates in aqueous solution to form nanoaggregates. Intermolecular π-π stacking interactions dominate molecular motion, suppressing non-radiative internal conversion processes and thus generating more triplet excitons. However, for polymer nanoaggregates, in addition to intermolecular π-π stacking interactions, the polymer shell contains a large number of heteroatoms such as oxygen, sulfur, and nitrogen. Hydrogen bonding interactions may exist between TPABZPy and the polymer, which helps restrict the molecular motion of the photosensitizer core. Figure 45 As shown, F127@TPABZPy nanoparticles and DSPE-PEG 2000 The fluorescence spectra of @TPABZPy nanoparticles and BSA@TPABZPy nanoparticles show that the fluorescence intensity of BSA@TPABZPy nanoparticles is higher than that of F127@TPABZPy nanoparticles and DSPE-PEG. 2000 The presence of TPABZPy nanoparticles is due to the positive charge of TPABZPy and the negative charge of BSA, potentially leading to electrostatic interactions between them. Therefore, multiple interactions (π-π stacking, hydrogen bonding, and electrostatic interactions) make it more difficult for TPABZPy to move within the BSA matrix, resulting in the nonradiative internal conversion inactivation of singlet excitons. This is likely the reason for the stronger fluorescence and ROS generation efficiency of TPABZPy in the BSA matrix.

[0184] Example 10

[0185] The theoretical energy levels of the S1, T1, and T2 states and their natural transition orbitals (NTO) are simulated to explain the optical properties of the photosensitizer and its ROS generation performance. For example... Figures 46-51As shown, these correspond to DMANpPy, TPANpPy, DMAAnPy, TPAAnPy, DMABZPy, and TPABZPy, respectively. For the four Np / An-based photosensitizers, due to the sufficient separation of holes and particles in the orbital electrons, their electronic transitions in the lowest singlet state (S1) are dominated by charge transfer (CT). In contrast, the S1 of the two BZ-based photosensitizers exhibits a mixed electronic transition with local exciton (LE) and CT, because the orbital electrons of the BZ building blocks partially overlap. This can be used to explain the higher brightness of the BZ-based photosensitizers compared to the Np / An-based photosensitizers, as LE transitions favor emission, but CT transitions quench fluorescence. The NTO of S1 differs between the Np / An-based and BZ-based photosensitizers, attributed to the larger dihedral angles of the donor and acceptor in the Np / An-based photosensitizers, which facilitates the formation of CT transitions with charge separation characteristics, while the smaller dihedral angles in the BZ-based photosensitizers help improve electron overlap, such as... Figure 52 As shown. Furthermore, the excitation energy levels of the S1, T1, and T2 states were calculated and compared. Clearly, the energy split (ΔEst) between S1 and T1 in the three TPA-substituted photosensitizers is smaller than that of their corresponding DMA-substituted photosensitizers. This is likely the reason for accelerating the ISC channel to enhance the triplet exciton, since, according to perturbation theory, the rate constant (KISC) of the ISC process is inversely proportional to ΔEst, thus improving ROS generation efficiency. The natural transition orbitals (NTOs) indicate that their S1 state is dominated by CT transitions, while the triplet states of T1 and T2 exhibit both LE and CT transitions. This mixed transition characteristic also facilitates improved spin-orbit coupling (SOC) between the singlet and triplet states, playing a crucial role in promoting the improved ROS efficiency of the ISC channel. Therefore, the above analysis can well explain why TPA-substituted photosensitizers have better ROS generation efficiency than DMA-substituted photosensitizers.

[0186] Example 11

[0187] Due to their high ROS production efficiency and deep red fluorescence, DMABZPy and TPABZPy were selected for subsequent biological experiments. In vitro fluorescence imaging was performed first to evaluate their effectiveness, thus commencing the biological research. Positively charged photosensitizers typically exhibit better mitochondrial targeting; this study investigated the ability of DMABZPy and TPABZPy to enter cellular mitochondria.

[0188] HepG2 cells were incubated with DMABZPy / TPABZPy at a concentration of 5 μM for 4 hours, and then co-incubated with Mitotracker green at a concentration of 200 nM for 30 minutes. Figure 53As shown, both DMABZPy and TPABZPy can enter cells well and exhibit bright red fluorescence. In HepG2 cells, the red fluorescence from the photosensitizers overlapped well with the green fluorescence from Mitotracker green, with Pearson correlation coefficients of 85% and 80%, respectively. Based on these results, DMABZPy and TPABZPy can enter cells and reside in the mitochondria, which predicts effective PDT results for the photosensitizers, as ROS can effectively disrupt mitochondria to induce cell death.

[0189] Example 12

[0190] This embodiment further investigates the performance of DMABZPy and TPABZPy in generating ROS in cells. The original H2DCF-DA probe showed no fluorescence in cells, but once it interacted with ROS, it exhibited bright green fluorescence.

[0191] The ROS efficiency of DMABZPy and TPABZPy in cells was detected using the H2DCF-DA probe. HepG2 cells were incubated with DMABZPy / TPABZPy for 4 hours, then co-incubated with the H2DCF-DA probe for 30 minutes, and then treated with 10% laser power at 543 nm. The results at different time points are shown below. Figure 54 As shown, a distinct green fluorescence was observed after 20 seconds of light treatment, indicating rapid ROS production in the cells. When the cells were further irradiated for a longer period, the green fluorescence became even stronger, attributed to the abundant ROS production. Clear observation of cell morphology in bright-field images revealed that, with the production of ROS, the prismatic shape of the original cells began to round out, indicating the onset of cell death.

[0192] The PDT efficiency of cancer cells was then quantitatively evaluated using standard methylthiazolyl tetrazolium (MTT) and live / dead cell co-staining assays.

[0193] HepG2 cells were incubated with different concentrations (0, 0.05, 0.1, 0.5, 1, 2 μM) of DMABZPy / TPABZPy. Figure 55A and B show the dark toxicity and in vitro PDT results of DMABZPy and TPABZPy, respectively. Cell viability exceeded 90% without white light irradiation, indicating better biocompatibility and sufficient safety. Even at low concentrations of photosensitizers, white light treatment effectively killed HepG2 cells. When the incubation concentration of DMABZPy was 50 nM, the cell death rate after light irradiation was close to 60%, while when the incubation concentration of TPABZPy was 100 nM, the cell viability after PDT treatment was approximately 40%. When the incubation concentration of both DMABZPy and TPABZPy was 2 μM, the cell death rate after light irradiation exceeded 90%.

[0194] Using fluorescein diacetate (FDA) and propidium iodide (PI) as fluorescent probes, the PDT results of DMABZPy and TPABZPy-PSs were directly verified by live / dead cell co-staining assay. HepG2 cells were co-incubated with fluorescein diacetate (FDA), PI, and DMABZPy / TPABZPy at concentrations of 2 μM, 8 μM, and 1 μM, respectively. Figure 56 As shown, no ROS was generated when the cells were not treated with light, and the bright green fluorescence of FDA from the cells indicated that the cells were able to survive. In contrast, after white light irradiation, the strong red fluorescence of PI from the cells indicated cell death. This suggests that DMABZPy and TPABZPy have good PDT effects in vitro and show great anti-cancer efficiency.

[0195] Example 13

[0196] DMABZPy (5 μM) and HepG2 cells were incubated for 30 minutes at pH 7.4 and pH 5.8, respectively. The results are as follows: Figure 57 As shown, DMABZPy exhibits significant red fluorescence in a cell culture environment at pH 7.4, and emits a brighter green fluorescence when cultured under weakly acidic conditions at pH 5.8.

[0197] Next, given the excellent therapeutic properties of DMABZPy and TPABZPy in vitro, we will study the in vivo PDT effect using 4T1 tumor-bearing mice as a model.

[0198] like Figure 58 As shown, 4T1 cells were implanted into mice for 7 days. PBS + light treatment and DMABZPy / TPABZPy + no light treatment served as the control group, while DMABZPy / TPABZPy + light treatment served as the experimental group. The 4T1 tumor-bearing mice were divided into groups based on the following light parameters: white light 400-700nm, 100mW / cm². 2The specific treatment procedure for the experimental group was as follows: DMABZPy / TPABZPy was injected into the tumors of mice, and the tumors were irradiated with white light two hours after the photosensitizer injection. During the 14-day treatment period, tumor size and mouse weight were monitored every two days. Figure 59 As shown in the top left figure, the mice in different groups gained weight slowly, reflecting that they were in good health.

[0199] After 14 days of treatment, if Figure 59 As shown in the lower right image, all mice were sacrificed, and tumor growth differed between the control and experimental groups. Figure 59 As shown in the upper right and lower left images, tumor growth in the control group was not inhibited, while tumor growth in the experimental group was slowed or even disappeared. This indicates that DMABZPy and TPABZPy have good PDT effects. The tumors were dissected and stained with H&E (hematoxylin and eosin), and the results are as follows. Figure 60 As shown, a large number of densely packed cells with intact cytoplasm were observed at the tumor site in the control group, but nuclear shrinkage and obvious abnormal cytoplasmic cavities were observed in the experimental group, indicating that PDT treatment can completely kill cancer cells.

[0200] In addition, H&E staining was performed on other organs, including the heart, liver, spleen, lungs, and kidneys, with results as follows: Figure 61 As shown, no obvious abnormalities were observed, preliminarily demonstrating that DMABZPy and TPABZPy are biosafety-free in major organs. To further investigate the biosafety of DMABZPy and TPABZPy after PDT, hematological data were collected from mice in the control and experimental groups. The results are as follows: Figure 62 As shown, the experimental group exhibited almost no changes in white blood cell (WBC), lymphocyte (Lymph), red blood cell (RBC), hemoglobin (HGB), hematocrit (HCT), mean corpuscular volume (MCV), mean corpuscular hemoglobin (MCH), mean corpuscular hemoglobin concentration (MCHC), red blood cell distribution width (RDW), platelet count (PLT), mean platelet volume (MPV), and platelet distribution width (PDW) compared to the control group. Based on these results, DMABZPy and TPABZPy are demonstrated to be biosafe and effective photosensitizers suitable for cancer treatment.

[0201] The experiments described above demonstrate that this invention, through the design of different electron donors and π-bridges, prepared a series of charged photosensitizers with AIE properties. Different electronic segments in the molecular structure possess unique functions. For example, the basic DMA group, with its stronger electron-donating ability, imparts a stronger ICT effect to the molecule, quenching fluorescence. However, it is easily protonated in acidic solutions, subsequently activating fluorescence and improving ROS generation efficiency. Unlike the DMA group, the benzene rotor containing the TPA donor renders the corresponding photosensitizer unresponsive to acidic factors. However, due to intramolecular motion limitations, the TPA-substituted photosensitizer exhibits higher fluorescence intensity and ROS generation efficiency in aggregated environments compared to the corresponding DMA-substituted photosensitizers, suppressing nonradiative internal conversion processes and generating more triplet excitons. Interestingly, TPABZPy shows better specificity for BSA, exhibiting enhanced fluorescence, redshifted emission, and improved ROS generation efficiency. This is mainly due to the intramolecular rotation limitations caused by various intermolecular interactions such as π-π stacking, hydrogen bonding, and electrostatic interactions. Representative DMABZPy and TPABZPy can target and label cellular mitochondria with better biocompatibility. In addition, the therapeutic effects of PDT in vivo were evaluated. Low-dose photosensitizer (2 μM) can completely kill cancer cells. DMABZPy and TPABZPy can effectively inhibit tumor growth, showing the potential for developing highly efficient PDT technology.

[0202] The technical solutions provided by the embodiments of the present invention have been described in detail above. Specific examples have been used to illustrate the principles and implementation methods of the embodiments of the present invention. The descriptions of the embodiments above are only for helping to understand the principles of the embodiments of the present invention. At the same time, for those skilled in the art, there will be changes in the specific implementation methods and application scope based on the embodiments of the present invention. Therefore, the content of this specification should not be construed as a limitation of the present invention.

Claims

1. An AIE-active photosensitizer, characterized in that: It is a compound having a D-π-A structure, wherein the D-π-A structure is a donor-π-acceptor structure selected from one of the following structures: ； ； 。 2. A method for preparing the AIE-active photosensitizer as described in claim 1, characterized in that: The preparation process includes: 4-(dimethylamino)phenylboronic acid pinacol ester, 1,4-dibromonaphthalene, and Pd(PPh3)4 are placed in a reaction vessel, and under nitrogen protection, THF and K2CO3 aqueous solution are added to react and yield DMANp-Br; DMANp-Br, 4-formylphenylboronic acid, and Pd(PPh3)4 are added to a reaction vessel, and under nitrogen protection, THF and K2CO3 aqueous solution are added to react and yield DMANp-CHO; DMANp-CHO and 1,4-dimethylpyridine iodide are dissolved in a solvent, and a few drops of piperidine are added to the mixture to react and yield the AIE active photosensitizer DMANpPy. The structure of DMANp-Br is as follows: ； The structure of DMANp-CHO is as follows: 。 3. The method for preparing an AIE-active photosensitizer according to claim 2, characterized in that: The preparation process of DMANpPy includes: 5 mmol of 1,4-dibromonaphthalene and 6 mmol of 4-(dimethylamino)phenylboronic acid pinacol ester, along with 0.02 equivalents of Pd(PPh3)4 based on the bromine-substituted product, were placed in a reaction vessel. Under nitrogen protection, 20 mL of THF and 2 M, 8 mL of K2CO3 aqueous solution were injected into the reaction vessel. The mixture was refluxed overnight, and the resulting product was purified to obtain DMANp-Br. 2 mmol of DMANp-Br and 3 mmol of 4-formylphenylboronic acid, and 0.02 equivalents of Pd(PPh3)4 based on bromine substitution were placed in a reaction vessel, which was then filled with N2. Under nitrogen protection, 20 mL of THF and 2 M, 8 mL of K2CO3 aqueous solution were injected into the reaction vessel, and the mixture was refluxed overnight to obtain DMANp-CHO. 0.5 mmol of DMANp-CHO and 0.7 mmol of 1,4-dimethylpyridine-1-iodide were dissolved in a THF / methanol mixture with a volume of 4 / 12. A few drops of piperidine were added to the mixture and the mixture was refluxed for 12 hours. DMANpPy was obtained by purification.

4. A method for preparing the AIE-active photosensitizer as described in claim 1, characterized in that: The preparation process includes: 9,10-dibromoanthracene, 4-formylphenylboronic acid, and Pd(PPh3)4 are placed in a reaction vessel. Under nitrogen protection, an aqueous solution of THF and K2CO3 is injected into the reaction vessel to react and obtain BrAn-CHO. Then, 4-(dimethylamino)phenylboronic acid pinacol ester, BrAn-CHO, and Pd(PPh3)4 are placed in a reaction vessel. Under nitrogen protection, an aqueous solution of THF and K2CO3 is injected into the reaction vessel to react and obtain DMAAn-CHO. DMAAn-CHO and 1,4-dimethylpyridine iodide are dissolved in a solvent, and a few drops of piperidine are added to the mixture to react and obtain the photosensitizer DMAAnPy. The structure of BrAn-CHO is as follows: ； The structure of DMAAn-CHO is as follows: 。 5. The method for preparing an AIE-active photosensitizer according to claim 4, characterized in that: The preparation process of DMAAnPy includes: 5 mmol of 9,10-dibromoanthracene and 6 mmol of 4-formylphenylboronic acid, and 0.02 equivalents of Pd(PPh3)4 based on bromine substitution were placed in a reaction vessel, purged with N2, and under nitrogen protection, 20 mL of THF and 2 M, 8 mL of K2CO3 aqueous solution were injected into the reaction vessel, and the reaction was refluxed overnight to obtain BrAn-CHO. 2 mmol of BrAn-CHO and 3 mmol of 4-(dimethylamino)phenylboronic acid pinacol ester, and 0.02 equivalents of Pd(PPh3)4 (based on bromine substitution) were placed in a reaction vessel, purged with N2, and under nitrogen protection, 20 mL of THF and 2 M, 8 mL of K2CO3 aqueous solution were injected into the reaction vessel. The mixture was refluxed overnight, and DMAAn-CHO was obtained after purification. 0.5 mmol of DMAAn-CHO and 0.7 mmol of 1,4-dimethylpyridine-1-iodide were dissolved in a THF / methanol mixture with a volume of 4 / 12. A few drops of piperidine were added to the mixture and the mixture was refluxed for 12 hours to obtain DMAAnPy.

6. A method for preparing the AIE-active photosensitizer as described in claim 1, characterized in that: 4,7-Dibromo-2,1,3-benzothiadiazole, 4-(dimethylamino)phenylboronic acid pinacol ester, and Pd(PPh3)4 were placed in a reaction vessel. Under nitrogen protection, THF and K2CO3 aqueous solution were injected into the reaction vessel to react and obtain DMABZ-Br. DMABZ-Br, 4-formylphenylboronic acid, and Pd(PPh3)4 were placed in a reaction vessel. Under nitrogen protection, THF and K2CO3 aqueous solution were injected into the reaction vessel to react and obtain DMABZ-CHO. DMABZ-CHO and 1,4-dimethylpyridine iodide were dissolved in a solvent, and a few drops of piperidine were added to the mixture to react and obtain the photosensitizer DMABZPy. The structure of DMABZ-Br is as follows: ； The structure of DMABZ-CHO is as follows: 。 7. The method for preparing an AIE-active photosensitizer according to claim 6, characterized in that: The preparation process of DMABZPy includes: placing 5 mmol of 4,7-dibromo-2,1,3-benzothiadiazole and 6 mmol of 4-(dimethylamino)phenylboronic acid pinacol ester, and 0.02 equivalents of Pd(PPh3)4 (based on bromide) into a reaction vessel, purging with N2, and injecting 20 mL of THF and 2 M, 8 mL of K2CO3 aqueous solution into the reaction vessel under nitrogen protection, and refluxing overnight to obtain DMABZ-Br; 2 mmol of DMABZ-Br, 3 mmol of 4-formylphenylboronic acid, and 0.02 equivalents of Pd(PPh3)4 (based on bromide) were placed in a reaction vessel, N2 was introduced, and under nitrogen protection, 20 mL of THF and 2 M, 8 mL of K2CO3 aqueous solution were injected into the reaction vessel. The mixture was refluxed overnight to obtain DMABZ-CHO. 0.5 mmol of DMABZ-CHO and 0.7 mmol of 1,4-dimethylpyridine-1-iodide were dissolved in a THF / methanol mixture with a volume of 4 / 12. A few drops of piperidine were added to the mixture and the mixture was refluxed for 12 hours to obtain DMABZPy.

8. The use of the AIE-active photosensitizer as described in claim 1 in the preparation of photodynamic therapy drugs.

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