Method for improving type I active oxygen efficiency of aggregation-induced emission type photosensitizer and application of AIE photosensitizer nano polymer

Abstract

The invention discloses a method for improving type I active oxygen efficiency of an aggregation-induced emission type photosensitizer and application of an AIE photosensitizer nano polymer, and belongs to the technical field of photosensitizer materials. The invention provides a method for improving the efficiency of I-type active oxygen of an aggregation-induced emission type photosensitizer. The improvement of free radical type ROS (reactive oxygen species) efficiency is realized in molecular design and polymer formation respectively. In the molecular design level, generation of II-type singlet oxygen is inhibited by optimizing an electron donor and an electron acceptor, so that generation of free radical type ROS is promoted. The hydrophilic photosensitizer polymer is formed by coating a small-molecule photosensitizer with amphiphilic high-molecular lipidosome at the formation level of the polymer, so that the efficiency of singlet oxygen generated by original small molecules is inhibited, and the generation of I-type ROS is further promoted.

Description

Technical Field

[0001] The present invention belongs to the technical field of photosensitizer materials, and in particular relates to a method for improving the efficiency of type I reactive oxygen species of aggregation-induced emission (AIE) photosensitizers and the application of AIE photosensitizer nanopolymers. Background Art

[0002] Photodynamic therapy (PDT) has unique advantages such as non-invasive / minimally invasive, strong controllability, good curative effect, and low drug resistance, and has important application values in clinical aspects such as cancer treatment, wound healing promotion, and anti-skin infection. Photosensitizers, oxygen, and excitation light sources are three important components in photodynamic therapy. By irradiating a photosensitizer with appropriate excitation light, triplet energy is generated, which then interacts with oxygen to produce reactive oxygen species (ROS). The generated ROS can effectively kill cancer cells and bacteria, thereby achieving the effect of treating diseases. However, due to typical tumor hypoxia caused by abnormal proliferation, apoptosis of tumor cells, and tumor vascular malformation, the efficiency of ROS generated by photosensitizers in tumors is reduced, seriously affecting the treatment effect of PDT. Therefore, designing and synthesizing new photosensitizers with low oxygen dependence to achieve high-efficiency ROS generation behavior in a hypoxic environment is expected to solve the problem of inefficient photodynamic therapy of traditional photosensitizers for tumors.

[0003] ROS can be divided into two categories. One is singlet oxygen mainly based on energy transfer, which has the problem of high oxygen dependence, while the other is type I ROS mainly based on electron transfer, which can still efficiently generate free radical-type ROS even at low oxygen concentrations. Therefore, precisely designing type I photosensitizers and improving their efficiency of generating free radical ROS has become an important research direction. Therefore, there is an urgent need for a method that can improve the efficiency of type I reactive oxygen species of aggregation-induced emission photosensitizers to solve the above problems. Summary of the Invention

[0004] To solve the above technical problems, the present invention proposes a method for improving the efficiency of type I reactive oxygen species of aggregation-induced emission photosensitizers and the application of AIE photosensitizer nanopolymers.

[0005] To achieve the above object, the present invention provides the following technical solutions:

[0006] The present invention provides a method for improving the efficiency of type I reactive oxygen species of aggregation-induced emission photosensitizers, comprising the following steps:

[0007] (1) Dissolve 4,7-dibromo-2,1,3-benzothiadiazole or 4,7-dibromo-2,1,3-benzoselenadiazole, a triphenylamine derivative, a catalyst, and a base in a mixed solution of an organic solvent and water to carry out a Suzuki reaction, and then through reflux, extraction, washing, drying, and column chromatography, an aggregation-induced emission photosensitizer is obtained;

[0008] (2) Dissolve the aggregation-induced emission photosensitizer and amphiphilic polymer liposome obtained in step (1) in an organic solvent to obtain a mixed solution; mix the obtained mixed solution with water, perform ultrasonic treatment, and then stir and filter to obtain the AIE photosensitizer nanopolymer.

[0009] The present invention provides a method for improving the efficiency of type I reactive oxygen species of aggregation-induced emission photosensitizers, and realizes the improvement of the efficiency of radical-type ROS in molecular design and polymer formation respectively. At the molecular design level, by optimizing the electron donor and electron acceptor, the generation of type II singlet oxygen is inhibited, thereby promoting the generation of radical-type ROS. At the polymer formation level, the small molecule photosensitizer is encapsulated by amphiphilic polymer liposomes to form a hydrophilic photosensitizer polymer, the efficiency of singlet oxygen generated by the original small molecule is inhibited, and the generation of type I ROS is further promoted.

[0010] Preferably, in step (1), the molar ratio of 4,7-dibromo-2,1,3-benzothiadiazole or 4,7-dibromo-2,1,3-benzoselenadiazole to the triphenylamine derivative, the catalyst and the base is (1 - 1.5):(2 - 4):(0.05 - 0.1):15.

[0011] Further, in step (1), the molar ratio of 4,7-dibromo-2,1,3-benzothiadiazole, the triphenylamine derivative, the catalyst and the base is 1.5:3.4:0.06:15.

[0012] Preferably, in step (1), the triphenylamine derivative includes one of 4-boronic acid triphenylamine and 4-boronic acid-4`,4`-dimethoxytriphenylamine.

[0013] Preferably, in step (1), the catalyst is tetrakis(triphenylphosphine)palladium; the base is one of K2CO3 and Na2CO3, and further preferably K2CO3.

[0014] Further, in step (1), the volume ratio of the organic solvent to water in the mixed solution of the organic solvent and water is 5:1.

[0015] Preferably, in step (1), the temperature of the Suzuki reaction is 80 - 100 °C, and the time is 10 - 14 h.

[0016] Further, in step (1), the temperature of the Suzuki reaction is 100 °C, and the time is 12 h.

[0017] Further, in step (1), the reflux time is 12 h and the reflux atmosphere is nitrogen; the extractant for extraction is dichloromethane (DCM), and the number of extraction times is three; the washing reagent is brine; the desiccant for drying is anhydrous sodium sulfate; the eluent for column chromatography is dichloromethane and petroleum ether, and the volume ratio of dichloromethane to petroleum ether is 1:30.

[0018] Preferably, in step (2), the mass ratio of the aggregation-induced emission photosensitizer to the amphiphilic polymer liposome is 1:2.

[0019] Further, in step (2), the amphiphilic polymer liposome is DSPE-PEG 2000 .

[0020] Preferably, in step (2), the stirring time is 36 h.

[0021] Preferably, in step (2), the volume ratio of the organic solvent to water is 1:10.

[0022] Further, in step (2), the ultrasonic treatment time is 5 min.

[0023] Further, in step (1) or step (2), the organic solvent is one of tetrahydrofuran and toluene.

[0024] The present invention provides an AIE photosensitizer nanopolymer, which is prepared according to the method for improving the type I reactive oxygen species efficiency of the aggregation-induced emission photosensitizer described in the above technical solution.

[0025] The present invention also provides the application of the AIE photosensitizer nanopolymer described in the above technical solution in the preparation of anti-tumor drugs.

[0026] Compared with the prior art, the present invention has the following advantages and technical effects:

[0027] By optimizing the intramolecular electron donor and electron acceptor, the present invention obtains an organic type I photosensitizer with bright solid-state luminescence, large Stokes shift and better photostability. Further, by coating the above organic type I photosensitizer with an amphiphilic polymer liposome, the prepared AIE photosensitizer nanopolymer not only has good water dispersibility, but also further improves the efficiency of the photosensitizer to generate type I ROS.

[0028] The in vitro cell fluorescence imaging results in the present invention show that DMTBSZ NPs and DMTBSeZ NPs can be rapidly phagocytosed by cells and show bright red fluorescence, and can also effectively generate O2 after white light irradiation. ·-Free radical type ROS such as ·OH. The results of cytotoxicity evaluation showed that DMTBSZ NPs had good biocompatibility with cells without white light irradiation, but after white light irradiation with appropriate power, most cancer cells were killed. The results of in vivo tumor experiments showed that DMTBSZ NPs could effectively inhibit the growth of tumors in mice. Brief Description of the Drawings

[0029] The drawings forming a part of this application are used to provide a further understanding of this application. The schematic embodiments of this application and their descriptions are used to explain this application and do not constitute an improper limitation to this application. In the drawings:

[0030] Figure 1 It is a synthetic route diagram of the compounds in Examples 1-3 and a schematic diagram of the synthesis process of the AIE photosensitizer nanopolymer;

[0031] Figure 2 It is a schematic diagram of the synthesis process of the AIE photosensitizer nanopolymer in Example 1;

[0032] Figure 3 It is a schematic diagram of the synthesis process of the AIE photosensitizer nanopolymer in Example 2;

[0033] Figure 4 It is a schematic diagram of the synthesis process of the AIE photosensitizer nanopolymer in Example 3;

[0034] Figure 5 It is a graph showing the increase in fluorescence intensity and a fluorescence effect diagram of the compound obtained in step (1) of Examples 2-3 in a dimethyl sulfoxide / water mixed solvent with the increase in water content;

[0035] Figure 6 It is a size distribution diagram of the AIE photosensitizer nanopolymer prepared in Examples 2-3 in an aqueous solution;

[0036] Figure 7 It is an ultraviolet-visible absorption spectrum diagram of different concentrations of DMTBSZ (A), a concentration-absorbance linear fitting relationship diagram of DMTBSZ (B), an ultraviolet absorption spectrum diagram of DMTBSZ NPs diluted 40 times (C), an ultraviolet absorption spectrum diagram of the same concentration of DMTBSZ and DMTBSZ NPs (D), an ultraviolet-visible absorption spectrum diagram of different concentrations of DMTBSeZ (E), a concentration-absorbance linear fitting relationship diagram of DMTBSeZ (F), an ultraviolet absorption spectrum diagram of DMTBSeZ NPs diluted 40 times (G), and an ultraviolet absorption spectrum diagram of the same concentration of DMTBSeZ and DMTBSeZ NPs (H);

[0037] Figure 8Fluorescence intensity change amplitude diagram after adding photosensitizer and irradiating with light in DMSO / aqueous solution containing H2DCF-DA probe, ABDA probe, DHR123 probe or HPF probe;

[0038] Figure 9 Fluorescence imaging diagrams of nuclear staining and co-staining of DMTBSZ NPs and Hoechst 33258 at different time points (A) and fluorescence imaging diagrams of nuclear staining and co-staining of DMTBSeZ NPs and Hoechst 33258 at different time points (B);

[0039] Figure 10 Fluorescence imaging diagrams of cell lysosome staining and co-staining of DMTBSZ NPs and Lysotracker green DND-26 (A) and fluorescence imaging diagrams of cell lysosome staining and co-staining of DMTBSeZ NPs and Lyso-Tracker green DND-26 (B);

[0040] Figure 11 Phototoxicity and dark toxicity evaluations of DMTBSZ NPs and DMTBSeZ NPs on 4T1 cells;

[0041] Figure 12 In vivo fluorescence imaging (A), comparison diagram of tumor size in mice (B), tumor growth inhibition (C) and change in mouse body weight (D) after the mouse is treated with DMTBSZ NPs; Detailed implementation manners

[0042] Next, the technical solutions in the embodiments of the present invention will be clearly and completely described in conjunction with the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts shall fall within the protection scope of the present invention.

[0043] To make the above objects, features, and advantages of the present invention more obvious and understandable, the present invention will be further described in detail below with reference to the accompanying drawings and specific implementation manners.

[0044] In the embodiments of the present invention, room temperature refers to "25±2°C".

[0045] Unless otherwise specified, the raw materials in the embodiments of the present invention are all obtained through commercial channels.

[0046] Example 1

[0047] A method for improving the type I reactive oxygen species efficiency of aggregation-induced emission photosensitizers, the specific steps are as follows:

[0048] (1) Synthesis of Compound DTBSZ

[0049] The synthetic route of DTBSZ is as follows:

[0050]

[0051] 4,7-Dibromo-2,1,3-benzothiazole (500 mg, 1.5 mmol), 4-(triphenylamino)benzoic acid (980 mg, 3.4 mmol), Pd(PPh3)4 (68 mg, 0.06 mmol) and anhydrous potassium carbonate (2.0 g, 15 mmol) were added to a mixed solvent of tetrahydrofuran and water (the volume ratio of tetrahydrofuran to water was 25 mL:5 mL). Then, the mixture was refluxed at 100 °C under nitrogen for 12 h. After cooling, the mixture was extracted three times with dichloromethane (DCM), then washed with brine, and the organic layer was dried over anhydrous sodium sulfate. Column chromatography was performed using DCM and petroleum ether (the volume ratio of DCM to petroleum ether was 1:30) as the eluent to obtain purple-red powder DTBSZ (512 mg) with a yield of 56%.

[0052] The characterization data of the obtained DTBSZ are as follows: 1 H NMR (400 MHz, CD2Cl2) δ 7.95 - 7.89 (m, 4H), 7.78 (s, 2H), 7.36 - 7.30 (m, 8H), 7.21 - 7.18 (m, 12H), 7.10 (t, J = 6.9 Hz, 4H). 13 C NMR (101 MHz, CDCl3) δ 154.16, 147.98, 147.49, 132.17, 131.07, 129.90, 129.36, 127.45, 124.89, 123.30, 122.95. HRMS (ESI) m / z: [M] + calcd for C 42 H 30 N4S, 622.2191; found, 622.2193.

[0053] (2) Synthesis of DTBSZ NPs

[0054] The DTBSZ (1.0 mg) obtained in step (1) and DSPE-PEG 2000 (2.0 mg) were fully dissolved in 1 mL of tetrahydrofuran, and then placed in 10 mL of distilled water. After ultrasonic treatment for 5 min, the resulting solution was slowly stirred for 36 h until tetrahydrofuran was removed, obtaining a clear aqueous solution, which was the nano-polymer DTBSZ NPs.

[0055] Example 2

[0056] A method for improving the efficiency of type I reactive oxygen species of aggregation-induced emission photosensitizers, the specific steps are as follows:

[0057] (1) Synthesis of compound DMTBSZ

[0058] The synthesis route of DMTBSZ is as follows:

[0059]

[0060] Add 4,7-dibromo-2,1,3-benzothiazole (500 mg, 1.5 mmol), 4-boronic acid-4`,4`-dimethoxytriphenylamine (1.19 g, 3.4 mmol), Pd(PPh3)4 (68 mg, 0.06 mmol) and anhydrous potassium carbonate (2.0 g, 15 mmol) to a mixed solvent of tetrahydrofuran and water (the volume ratio of tetrahydrofuran to water is 25 mL:5 mL), then reflux at 100 °C under nitrogen for 12 h. After the mixture is cooled, extract it three times with dichloromethane (DCM), then wash it with brine, and then dry the organic layer with anhydrous sodium sulfate. Then use DCM and petroleum ether (the volume ratio of DCM to petroleum ether is 1:30) as the eluent for column chromatography to obtain purple-red powder DMTBSZ (610 mg), with a yield of 56%.

[0061] The characterization data of the obtained DMTBSZ are as follows: 1 H NMR (400 MHz, CD2Cl2) δ 7.82 (d, J = 8.8 Hz, 4H), 7.70 (s, 2H), 7.15 - 7.09 (m, 8H), 7.01 (d, J = 8.8 Hz, 4H), 6.91 - 6.84 (m, 8H), 3.80 (s, 12H). 13 C NMR (101 MHz, CDCl3) δ 156.12, 154.24, 148.81, 140.62, 132.05, 129.70, 129.12, 127.10, 127.01, 119.84, 114.77, 55.52. HRMS (ESI) m / z: [M + H] + calcd for C 46 H 38 N4O4S, 743.2687; found, 743.2681.

[0062] (2) Synthesis of DMTBSZ NPs

[0063] Add the DMTBSZ (1.0 mg) obtained in step (1) and DSPE-PEG 2000(2.0 mg) was fully dissolved in 1 mL of tetrahydrofuran, then placed in 10 mL of distilled water, sonicated for 5 min, and the resulting solution was slowly stirred for 36 h until the tetrahydrofuran was removed to obtain a clear aqueous solution, which was DMTBSZ NPs.

[0064] Example 3

[0065] A method for improving the type I reactive oxygen species efficiency of aggregation-induced emission photosensitizers, the specific steps are as follows:

[0066] (1) Synthesis of compound DMTBSeZ

[0067] The synthesis route of DMTBSeZ is:

[0068]

[0069] 4,7-Dibromo-2,1,3-benzoselenadiazole (500 mg, 1.5 mmol), 4-boronic acid-4`,4`-dimethoxytriphenylamine (1.19 g, 3.4 mmol), Pd(PPh3)4 (68 mg, 0.06 mmol) and anhydrous potassium carbonate (2.0 g, 15 mmol) were added to a mixed solvent of tetrahydrofuran and water (the volume ratio of tetrahydrofuran to water is 25 mL:5 mL), and then refluxed at 100 °C under nitrogen for 12 h. After the mixture was cooled, it was extracted three times with dichloromethane (DCM), then washed with brine, and then the organic layer was dried with anhydrous sodium sulfate. Column chromatography was performed using DCM and petroleum ether (the volume ratio of DCM to petroleum ether is 1:30) as the eluent to obtain a purple-red powder DMTBSeZ (615 mg) with a yield of 53%.

[0070] The characterization data of the obtained DMTBSeZ are as follows: 1 H NMR (400 MHz, CD2Cl2) δ 7.73 (d, J = 8.4 Hz, 4H), 7.54 (s, 2H), 7.11 (s, 8H), 6.99 (s, 4H), 6.87 (d, J = 8.8 Hz, 8H), 3.80 (s, 12H). 13 C NMR (101 MHz, CDCl3) δ 159.98, 156.09, 148.69, 140.67, 133.89, 129.99, 129.80, 127.59, 126.99, 119.77, 114.76, 55.52. HRMS (ESI) m / z: [M+H] + calcd for C 46 H 38 N4O4Se, 791.2131; found, 791.2131.

[0071] (2) Synthesis of Compound DMTBSeZ NPs

[0072] Dissolve the DMTBSeZ (1.0 mg) obtained in step (1) and DSPE-PEG 2000 (2.0 mg) completely in 1 mL of tetrahydrofuran, then place it in 10 mL of distilled water, sonicate for 5 min, and slowly stir the resulting solution for 36 h until the tetrahydrofuran is removed to obtain a clear aqueous solution, which is DMTBSeZ NPs.

[0073] Figure 1 It is the synthetic route diagram of the compounds in Examples 1-3 and the schematic diagram of the synthesis process of the AIE photosensitizer nanopolymer.

[0074] Figure 2 It is the schematic diagram of the synthesis process of the AIE photosensitizer nanopolymer in Example 1.

[0075] Figure 3 It is the schematic diagram of the synthesis process of the AIE photosensitizer nanopolymer in Example 2.

[0076] Figure 4 It is the schematic diagram of the synthesis process of the AIE photosensitizer nanopolymer in Example 3.

[0077] Figure 5 It is the fluorescence intensity increase diagram and fluorescence effect diagram of the compounds obtained in step (1) of Examples 2-3 in the dimethyl sulfoxide / water mixed solvent with the increase of water content. Among them, (A) is the fluorescence intensity increase diagram of DMTBSZ and DMTBSeZ, (B) is the fluorescence effect diagram of DMTBSZ, and (C) is the fluorescence effect diagram of DMTBSeZ. From Figure 5 it can be seen that with the addition of the poor solvent water, the fluorescence intensities of both compounds are higher than those in the pure dimethyl sulfoxide solvent, indicating that both compounds DMTBSZ and DMTBSeZ have AIE properties.

[0078] Use a laser particle size analyzer to test the size distribution of the AIE photosensitizer nanopolymers prepared in Examples 2-3, and the results are shown in Figure 6 . Figure 6 It is the size distribution diagram of the AIE photosensitizer nanopolymers prepared in Examples 2-3 in aqueous solution. Among them, (A) is DMTBSZ NPs and (B) is DMTBSeZ NPs. From Figure 6 it can be seen that the sizes of both photosensitizers are mainly concentrated around 135 nm, indicating that they have a high surface area to volume ratio, thus ensuring higher solubility and faster dissolution rate. Such small particles also have a longer circulation time in the bloodstream and enhanced permeability and retention effects in tumor tissues.

[0079] Figure 7 UV-Vis absorption spectra of DMTBSZ at different concentrations (A), concentration-absorbance linear fitting relationship diagram of DMTBSZ (B), UV absorption spectrum of DMTBSZ NPs diluted 40 times (C), UV absorption spectra of DMTBSZ and DMTBSZ NPs at the same concentration (D), UV-Vis absorption spectra of DMTBSeZ at different concentrations (E), concentration-absorbance linear fitting relationship diagram of DMTBSeZ (F), UV absorption spectrum of DMTBSeZ NPs diluted 40 times (G), and UV absorption spectra of DMTBSeZ and DMTBSeZ NPs at the same concentration (H). According to Figure 7 the UV absorption spectra of the nanopolymers (DMTBSZ NPs and DMTBSeZ NPs) in , the concentration of the nanopolymers was obtained, and then the encapsulation efficiency was calculated. Finally, it was concluded that the encapsulation efficiency of both nanopolymers was greater than 40%, indicating that the AIE photosensitizer was effectively coated by the amphiphilic nanopolymers, making drug delivery smoother. The photosensitizer concentration in the experimental group was verified to be strictly consistent by UV-Vis spectrophotometry to ensure the comparability of subsequent experimental data.

[0080] Figure 8 Fluorescence intensity change amplitude diagrams after adding photosensitizers and irradiating in DMSO / aqueous solutions containing H2DCF-DA probe, ABDA probe, DHR123 probe or HPF probe; among them, (A) is the fluorescence intensity change amplitude diagram after adding DMTBSZ and DMTBSZ NPs and irradiating in DMSO / aqueous solution containing H2DCF-DA probe, λ ex = 488 nm; (B) is the absorption intensity change amplitude diagram after adding DMTBSZ, DMTBSeZ, DMTBSZ NPs and DMTBSeZ NPs and irradiating in the solution containing ABDA probe, λ abs = 400 nm; (C) is the fluorescence intensity change amplitude diagram after adding DMTBSZ, DMTBSeZ, DMTBSZ NPs and DMTBSeZ NPs and irradiating in DMSO / aqueous solution containing DHR123 probe, λ ex = 490 nm; (D) is the fluorescence intensity change amplitude diagram after adding DMTBSZ and DMTBSZ NPs and irradiating in DMSO / aqueous solution containing HPF probe, λ ex = 490 nm. It can be seen from Figure 8 part (A) in that the efficiency of reactive oxygen species of the small molecule compound DMTBSZ was significantly improved overall after co-assembling with the polymer to form nanoparticles, indicating that the co-assembly strategy of amphiphilic polymers and AIE-active photosensitizers not only provides better water dispersibility but also helps to improve the efficiency of photosensitizers in generating ROS. FromFigure 8 As can be seen from part (B), after the compounds DMTBSZ and DMTBSeZ are co-assembled with a polymer to form nanoparticles, the singlet oxygen generated under light irradiation is generally inhibited. Singlet oxygen is a reactive oxygen species generated through triplet energy transfer between a photosensitizer and oxygen. After the AIE photosensitizer is coated with a polymer, multiple interactions (such as π-π stacking and electrostatic interactions) between the two components weaken the originally weak energy transfer ability, so the singlet oxygen generation ability of the nanopolymer photosensitizer is inhibited. From Figure 8 As can be seen from part (C), after the compounds DMTBSZ and DMTBSeZ are co-assembled with a polymer to form nanoparticles, the efficiency of generating superoxide anions under light irradiation is greatly improved. Under light irradiation, the photosensitizer that undergoes intersystem crossing to the triplet excited state transfers an electron to the surrounding oxygen to generate superoxide anions, which are reactive oxygen species with a radical nature. After the AIE photosensitizer is coated with a polymer, due to the presence of a large number of heteroatoms such as oxygen, phosphorus, and nitrogen in the polymer shell, this helps the photosensitizer to transfer electrons and sensitize the generation of superoxide anion radicals. From Figure 8 As can be seen from part (D), for the small molecule compound DMTBSZ, after co-assembling with a polymer to form nanoparticles, the efficiency of generating hydroxyl radicals is improved, indicating that polymer coating can improve the ability of the photosensitizer to generate hydroxyl radical-type reactive oxygen species.

[0081] After culturing mouse cancer 4T1 cells in the medium for 24 h, 5 μM of DMTBSZ NPs, 10 μM of Hoechst 33258 (specific DNA dye), 5 μM of DMTBSeZ NPs, PBS solutions of 5 μM DMTBSZ NPs and 0.2 μM Hoechst 33258, and PBS solutions of 5 μM DMTBSeZ NPs and 0.2 μM Hoechst 33258 were added to the medium respectively. After acting at 37 °C for 2 h, 4 h, and 6 h respectively, they were washed 3 times with PBS, and imaging characterization was performed with a laser confocal microscope. The results are shown in Figure 9 。

[0082] Figure 9 are the fluorescence imaging diagrams of nuclear staining and co-staining of DMTBSZ NPs and Hoechst 33258 at different time points (A) and the fluorescence imaging diagrams of nuclear staining and co-staining of DMTBSeZ NPs and Hoechst 33258 at different time points (B), where [DMTBSZ NPs] = 5 μM, λ ex = 490 nm, λ em = 550 - 700 nm; [DMTBSeZ NPs] = 5 μM, λ ex = 510 nm, λ em= 550 - 700 nm; [Hoechst 33258] = 10 μM, λ ex = 350 nm, λ em = 370 - 500 nm, scale bar = 50 μm. From Figure 9 The results show that in 4T1 cells, NPs emit weak red fluorescence after 4 h, indicating that NPs are internalized by the cells. As the incubation time is extended to 6 h, the red fluorescence becomes stronger, indicating that NPs accumulate in 4T1 cells.

[0083] After culturing mouse cancer 4T1 cells in the medium for 24 h, 5 μM of DMTBSZ NPs, 200 nM of Lyso-Tracker Green DND-26 (lysosome green fluorescent probe), 5 μM of DMTBSeZ NPs, PBS solutions of 5 μM DMTBSZ NPs and 200 nM Lyso-Tracker Green DND-26, and PBS solutions of 5 μM DMTBSeZ NPs and 200 nM Lyso-Tracker Green DND-26 were added to the medium respectively. After acting at 37 °C for 24 h respectively, they were washed 3 times with PBS and imaged and characterized with a laser confocal microscope. The results are shown in Figure 10 .

[0084] Figure 10 are the fluorescence imaging diagrams (A) of DMTBSZ NPs and Lysotracker green DND-26 for cell lysosome staining and co-staining and (B) of DMTBSeZ NPs and Lyso-Tracker green DND-26 for cell lysosome staining and co-staining. Among them, [DMTBSZ NPs] = 5 μM, λ ex = 490 nm, λ em = 550 - 700 nm; [DMTBSeZ NPs] = 5 μM, λ ex = 510 nm, λ em = 550 - 700 nm; [Lyso-Tracker green DND-26] = 200 nM, λ ex = 488 nm, λ em = 500 - 550 nm, scale bar = 50 μm. From Figure 10 The results show that the high overlap of the red fluorescence of NPs and the green fluorescence of Lyso-Tracker indicates that NPs accumulate in lysosomes.

[0085] Mouse cancer 4T1 cells were grown in a confocal imaging dish at 37°C under normal conditions. After incubating the cells with complete medium for 12 h, the complete medium was replaced with drug-containing medium at a drug concentration of 20 μM and incubated for another 12 h. The cells were exposed to 30 mW cm -2 The cells were irradiated with white light for 30 min, incubated at 37°C for 12 h, and then stained with medium containing 2 μM calcein (live cell dye) and 4 μM ethidium bromide dimer 1 (dead cell dye) for 30 min. The stained cells were imaged using a laser confocal microscope. The results are shown in Figure 11 Among them, the cell incubation scheme is as follows:

[0086] ℃DMTBSZ NPs illumination group: drug-containing medium plus DMTBSZ NPs, incubation condition is illumination;

[0087] ℃DMTBSeZ NPs illumination group: drug-containing medium plus DMTBSeZ NPs, incubation condition is illumination;

[0088] ℃DMTBSZ NPs group: drug-containing medium plus DMTBSZ NPs, incubation conditions were no light;

[0089] °CDMTBSeZ NPs group: drug-containing medium plus DMTBSeZ NPs, incubation conditions were no light;

[0090] ℃Blank group: culture medium plus physiological saline, incubation condition is light.

[0091] Figure 11 Phototoxicity and dark toxicity evaluation of DMTBSZ NPs and DMTBSeZ NPs on 4T1 cells; [calcein] = 2 μM, [ethidium bromide dimer 1] = 4 μM. Figure 11 It can be seen that the cells cultured with NPs were stained with dead cell dyes on a large scale after light treatment, while the cells without light treatment remained active, indicating that DMTBSZ NPs and DMTBSeZ NPs have good cellular phototoxicity and almost no biological dark toxicity to cells, showing good photodynamic therapy effects.

[0092] Using 4T1 mouse breast cancer cells as a model, they were implanted subcutaneously on the right back of the mouse to establish a tumor animal model. When the subcutaneous tumor size of the mouse was 70 mm 3 Afterwards, the drug was injected intratumorally twice on the 1st and 7th days, and 200 mW cm -2White light was used to irradiate for 20 min for white light therapy, while the blank group, the PBS non-irradiation group, and the DMTBSZ NPs non-irradiation group were not given drugs on the seventh day. After the treatment cycle (14 days) ended, the changes in the tumor volume and body weight of the mice were recorded every two days, and the results are shown in Figure 12 . Among them, the treatment plan is as follows:

[0093] ℃ PBS irradiation group (PBS + Light): PBS was injected, the dosage was 100 μL, the administration concentration was 100 μM, and white light therapy was carried out;

[0094] ℃ Blank group (Control): Normal saline was injected, the dosage was 100 μL, the administration concentration was 100 μM, and white light therapy was carried out;

[0095] ℃ PBS non-irradiation group (PBS): PBS was injected, the dosage was 100 μL, the administration concentration was 100 μM, and white light therapy was not carried out;

[0096] ℃ DMTBSZ NPs non-irradiation group (DMTBSZ NPs): DMTBSZ NPs were injected, the dosage was 100 μL, the administration concentration was 100 μM, and white light therapy was not carried out;

[0097] ⑤ DMTBSZ NPs irradiation group (DMTBSZ NPs + Light): DMTBSZ NPs were injected, the dosage was 100 μL, the administration concentration was 100 μM, and white light therapy was carried out.

[0098] Figure 12 are the in vivo fluorescence imaging (A) of mice after the interaction with DMTBSZ NPs, the comparison chart of tumor size in mice (B), the tumor growth inhibition situation (C), and the change in body weight of mice (D). From Figure 12 part (A), it can be seen that after injecting DMTBSZ NPs into the tumor for 2 h, the in vivo fluorescence imaging was obvious and the signal-to-noise ratio was low, indicating that the photosensitizer had good in vivo fluorescence imaging effect. From Figure 12 parts (B) and (C), it can be seen that the tumors in the DMTBSZ NPs non-irradiation group without photodynamic therapy proliferated rapidly, while after photodynamic therapy, the growth of tumors could be effectively inhibited, indicating that DMTBSZ NPs still had good effects in in vivo tumor treatment. In addition, Figure 12 part (D) shows that the body weight growth trends of the mice in all experimental groups were the same, indicating that the mice in the DMTBSZ NPs irradiation group with photodynamic therapy did not have the inhibition of tumor growth due to other reasons.

[0099] The above are only the preferred specific embodiments of the present application, but the protection scope of the present application is not limited thereto. Any changes or substitutions that can be easily conceived by those skilled in the art within the technical scope disclosed in the present application should be covered by the protection scope of the present application. Therefore, the protection scope of the present application should be subject to the protection scope of the claims.

Claims

1. A method for improving the efficiency of type I reactive oxygen species of aggregation-induced emission photosensitizers, characterized in that, It includes the following steps: (1) Dissolve 4,7-dibromo-2,1,3-benzothiadiazole or 4,7-dibromo-2,1,3-benzoselenadiazole, a triphenylamine derivative, a catalyst, and a base in a mixed solution of an organic solvent and water to carry out the Suzuki reaction, and then through reflux, extraction, washing, drying, and column chromatography to obtain an aggregation-induced emission photosensitizer; (2) Dissolve the aggregation-induced emission photosensitizer obtained in step (1) and an amphiphilic polymer liposome in an organic solvent to obtain a mixed solution; after mixing the obtained mixed solution with water, perform ultrasonic treatment, and then through stirring and filtration to obtain an AIE photosensitizer nanopolymer.

2. The method for improving the efficiency of type I reactive oxygen species of the aggregation-induced emission photosensitizer according to claim 1, wherein In step (1), the molar ratio of the 4,7-dibromo-2,1,3-benzothiadiazole or 4,7-dibromo-2,1,3-benzoselenadiazole, the triphenylamine derivative, the catalyst, and the base is (1 - 1.5):(2 - 4):(0.05 - 0.1):

15.

3. The method for improving the type I reactive oxygen species efficiency of the aggregation-induced emission photosensitizer according to claim 1 or 2, characterized in that, In step (1), the triphenylamine derivative includes one of 4-boronic acid triphenylamine and 4-boronic acid-4`,4`-dimethoxytriphenylamine.

4. The method for improving the type I reactive oxygen species efficiency of the aggregation-induced emission photosensitizer according to claim 1, wherein In step (1), the catalyst is tetrakis(triphenylphosphine)palladium; the base is one of K2CO3 and Na2CO3.

5. The method for improving the type I reactive oxygen species efficiency of the aggregation-induced emission photosensitizer according to claim 1, characterized in that In step (1), the temperature of the Suzuki reaction is 80 - 100 °C, and the time is 10 - 14 h.

6. The method for improving the type I reactive oxygen species efficiency of the aggregation-induced emission photosensitizer according to claim 1, characterized in that, In step (2), the mass ratio of the aggregation-induced emission photosensitizer and the amphiphilic polymer liposome is 1:

2.

7. The method for improving the efficiency of type I reactive oxygen species of the aggregation-induced emission photosensitizer according to claim 1, wherein In step (2), the stirring time is 36 h.

8. The method for improving the type I reactive oxygen species efficiency of the aggregation-induced emission photosensitizer according to claim 1, characterized in that, In step (2), the volume ratio of the organic solvent and water is 1:

10.

9. An AIE photosensitizer nanopolymer, characterized in that, It is prepared by the method for improving the type I reactive oxygen species efficiency of the aggregation-induced emission photosensitizer according to any one of claims 1 to 8.

10. Use of the AIE photosensitizer nanopolymer according to claim 9 in the preparation of a drug for treating tumors.

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