Photosensitizer, preparation and application thereof, and anti-tumor nanoparticles

Abstract

The invention discloses a photosensitizer, preparation and application thereof and anti-tumor nanoparticles. According to the invention, 2, 4-dinitrobenzenesulfonyl chloride is grafted on a photosensitizer THPP to obtain SO2 prodrug photosensitizer molecules sensitive to glutathione, SO2 gas molecules can be released at tumor sites through a reaction between sulfonate groups in the molecules and over-expressed GSH in tumor cells, the tumor cells are further induced to generate high-toxicity reactive oxygen species, and the activity of glutathione in the tumor cells is enhanced. And the photodynamic therapy effect of THPP is enhanced. The preparation method comprises the following steps: respectively dissolving THPP and DNs in an organic solvent to obtain a first solution and a second solution; adding triethylamine into the first solution, stirring in an ice-water bath, adding the second solution, and stirring for reaction to obtain a final product. The photosensitizer can be applied to preparation of anti-tumor nanoparticles. According to the invention, SO2 gas treatment and photodynamic treatment are organically combined, and efficient treatment of tumor cells is realized by utilizing mutual synergistic interaction of SO2 gas treatment and photodynamic treatment.

Description

Technical Field

[0001] The present invention relates to an anti-tumor photodynamic therapy drug, and particularly to a photosensitizer and its preparation, application, and anti-tumor nanoparticles. Background Art

[0002] Tumor photodynamic therapy is an innovative cancer treatment method. It is based on the principle that a photosensitizer specifically accumulates in tumor tissues, and then is irradiated with light of a specific wavelength to activate the photosensitizer to generate reactive oxygen species such as singlet oxygen, thereby destroying the structure and function of tumor cells, inducing apoptosis or necrosis of cells, and achieving precise anti-cancer. This therapy has significant advantages. On the one hand, targeted therapy can minimize damage to surrounding normal tissues to the greatest extent and reduce side effects. On the other hand, it can be used for multiple treatments and is also suitable for some patients who cannot tolerate surgery, radiotherapy, or chemotherapy, such as the elderly and the weak. In clinical applications, it has been carried out in many fields such as skin cancer, nasopharyngeal cancer, and bladder cancer. However, it also faces challenges. For example, the optimization of photosensitizers requires both improving tumor targeting and reducing toxicity and side effects. There is also the problem of light penetration depth, which limits its efficacy for deep tumors. Secondly, most tumor sites are hypoxic microenvironments, and photodynamic therapy requires the participation of oxygen, and its treatment efficiency is further limited.

[0003] Gas therapy mainly uses therapeutic gases such as nitric oxide (NO), carbon monoxide (CO), hydrogen sulfide (H2S), sulfur dioxide (SO2), etc. to replace traditional chemotherapy drugs to intervene in the disease process. Common therapeutic gases such as nitric oxide can dilate vascular smooth muscle, regulate blood pressure, and improve blood flow in the treatment of cardiovascular diseases. In the treatment of lung diseases, it can assist in the treatment of pulmonary hypertension, acute respiratory distress syndrome, etc. and promote gas exchange. Carbon dioxide gas also has its uses. Inhaling a low concentration of carbon dioxide appropriately can stimulate the respiratory center and is used to treat respiratory depression. There is also hydrogen, which has antioxidant and anti-inflammatory properties and has potential protective effects on neurological diseases, liver damage, etc. Gas therapy has obvious advantages. It can quickly diffuse throughout the body, has strong targeting, and is convenient for drug administration. Among them, sulfur dioxide (SO2) gas therapy shows great potential in the field of tumor treatment. It can disrupt the redox balance in tumor cells, increase the concentration of reactive oxygen species in tumor cells, cause mitochondrial dysfunction and oxidative damage of biological macromolecules, and then induce apoptosis of tumor cells. Research shows that the combination of these therapeutic gas molecules with traditional tumor chemotherapy, photodynamic therapy, photothermal therapy, etc. can enhance the tumor treatment effect. Therefore, how to design an efficient anti-tumor photosensitizer with both gas molecule treatment functions has become a technical problem to be solved urgently. Summary of the Invention

[0004] Objects of the Invention: The object of the present invention is to provide a photosensitizer with both photodynamic therapy and gas therapy functions. Another object of the present invention is to propose a preparation method of the photosensitizer to solve the problem of how to prepare a photosensitizer with both photodynamic therapy and gas therapy functions. The third object of the present invention is to provide an application of the photosensitizer in the preparation of anti-tumor drugs to solve the problem of how to prepare a nano-therapeutic agent for photodynamic therapy with the function of targeting tumor cells and in-situ controlled release of SO2. The fourth object of the present invention is to provide an anti-tumor nanoparticle for photodynamic therapy that targets tumor cells and in-situ controlled releases SO2.

[0005] Technical Solution: A photosensitizer according to the present invention has the following structural formula:

[0006]

[0007] The present invention combines two tumor treatment methods, photodynamic therapy and high-concentration SO2 gas therapy, and the synergistic effect of the two realizes the efficient treatment of tumor cells. The present invention constructs a glutathione (GSH)-sensitive SO2 prodrug photosensitizer molecule by grafting 2,4-dinitrobenzenesulfonyl chloride onto 5,10,15,20-tetrakis(4-hydroxyphenyl)porphyrin. By reacting the sulfonate group in the molecule with the overexpressed GSH in tumor cells, SO2 gas molecules can be released at the tumor site, further inducing the generation of highly toxic reactive oxygen species in tumor cells and enhancing the photodynamic therapy effect of THPP.

[0008] The second aspect of the present invention discloses a preparation method of the above-mentioned photosensitizer, which includes the following steps:

[0009]

[0010] Preferably, the base is triethylamine or diisopropylethylamine.

[0011] Preferably, the molar ratio of 5,10,15,20-tetrakis(4-hydroxyphenyl)porphyrin to 2,4-dinitrobenzenesulfonyl chloride is 1:3-8.

[0012] Preferably, the specific reaction steps of 5,10,15,20-tetrakis(4-hydroxyphenyl)porphyrin and 2,4-dinitrobenzenesulfonyl chloride include:

[0013] Dissolve 5,10,15,20-tetrakis(4-hydroxyphenyl)porphyrin in an organic solvent to obtain a first solution; dissolve 2,4-dinitrobenzenesulfonyl chloride in an organic solvent to obtain a second solution; add triethylamine to the first solution, stir in an ice-water bath, and then add the second solution, and stir and react to obtain a photosensitizer molecule. The reaction time is 12-36 h.

[0014] Preferably, the organic solvent includes at least one of tetrahydrofuran, dimethyl sulfoxide, dimethylformamide, and dichloromethane.

[0015] The third aspect of the present invention discloses the application of the above-mentioned photosensitizer in the preparation of anti-tumor drugs.

[0016] Preferably, the preparation method of the anti-tumor drug includes the following steps:

[0017] Dissolve the photosensitizer in an organic solvent to obtain a third solution, dissolve phosphatidylethanolamine-polyethylene glycol-folic acid in water to obtain a fourth solution, drop the fourth solution into the third solution, and dialyze after stirring and reacting at room temperature to obtain the anti-tumor drug.

[0018] In order to improve the efficiency of the photosensitizer entering tumor cells, the present invention co-assembles the polymer phosphatidylethanolamine-polyethylene glycol-folic acid (FA-PEG-DSPE) with tumor targeting function and the above-mentioned photosensitizer THPP-DNs to form nanoparticles, endowing the nano-therapeutic agent with excellent dispersibility, biocompatibility and tumor targeting.

[0019] In some embodiments, the method of dialysis after stirring and reacting at room temperature is to stir and react at an ambient temperature of 20-25 °C for 12-24 h and then dialyze with a dialysis bag with a molecular weight cut-off of 10000-13000.

[0020] Preferably, the mass ratio of the photosensitizer to phosphatidylethanolamine-polyethylene glycol-folic acid is 1:2.5-3.

[0021] The fourth aspect of the present invention discloses an anti-tumor nanoparticle, which includes a hydrophobic core and a hydrophilic shell wrapped outside it. The hydrophobic core is the above-mentioned photosensitizer molecule; the hydrophilic shell is a folic acid-modified PEG long-chain molecule. The hydrophobic core is formed by self-assembly of the above-mentioned photosensitizer molecule and folic acid-modified PEG long-chain molecule (FA-PEG-DSPE).

[0022] Beneficial effects: Compared with the prior art, the present invention has the following remarkable advantages:

[0023] The present invention organically combines two tumor treatment methods, gas therapy and photodynamic therapy, through a photosensitizer molecule, and utilizes the mutual synergistic effect to achieve efficient treatment of tumor cells, and the inhibition rate of tumor cells can reach more than 97%. The photosensitizer molecule can be used in the preparation of anti-tumor nanoparticles, making the anti-tumor drug have excellent dispersibility, biocompatibility, tumor targeting and high tumor killing effect, and has good application prospects. Description of the Drawings

[0024] Figure 1 It is the nuclear magnetic resonance hydrogen spectrum of the photosensitizer molecule THPP-DNs in the present invention;

[0025] Figure 2 The results of SO2 gas release of the photosensitizer molecule in the GSH solution in the present invention;

[0026] Figure 3 Scanning electron microscopy image of self-assembled THPP-DNs@FA nanoparticles;

[0027] Figure 4 Fluorescence image of SO2 release of THPP-DNs@FA nanoparticles in tumor cells;

[0028] Figure 5 Fluorescence image of singlet oxygen in HeLa cells after treatment with different experimental groups;

[0029] Figure 6 Antitumor efficacy evaluation chart of THPP-DNs@FA nanoparticles at the cellular level. Detailed implementation mode

[0030] The technical solution of the present invention will be further described below with reference to the accompanying drawings.

[0031] Example 1: The synthesis method of the photosensitizer molecule THPP-DNs is as follows:

[0032]

[0033] Weigh 67.80 mg (0.1 mmol) of 5,10,15,20-tetra(4-hydroxyphenyl)porphyrin (THPP) and add it to a 50 mL round-bottom flask. Add 5 mL of tetrahydrofuran to dissolve it, and prepare a tetrahydrofuran solution of porphyrin at 13.56 mg / mL. Then add 300 μL of triethylamine and stir in an ice-water bath for 30 min. Next, dissolve 106.4 mg (0.4 mmol) of 2,4-dinitrobenzenesulfonyl chloride (DNs) in 5 mL of tetrahydrofuran solution and add it to the above solution. Continue stirring and reacting for 24 h, then filter to collect the liquid, extract the aqueous layer with tetrahydrofuran to obtain a mixture; evaporate the mixture to obtain a crude product, and then purify it with a flash chromatography column (the volume ratio of methanol to dichloromethane is 1:20) to obtain the photosensitizer molecule THPP-DNs of the porphyrin derivative; the yield of the product is 54.2%;

[0034] Figure 1 1H NMR spectrum (room temperature, 400 MHz, DMSO-d6) of the photosensitizer molecule THPP-DNs of the porphyrin derivative proves the successful preparation of the target compound. 11H NMR (400 MHz, DMSO) δ 9.24 (d, J = 2.2 Hz, 4H), 8.80 (dd, J = 8.8, 2.3 Hz, 12H), 8.61 (d, J = 8.8 Hz, 4H), 8.28 (d, J = 8.5 Hz, 8H), 7.64 (d, J = 8.6 Hz, 8H), 2.02–1.95 (m, 2H), -3.03 (d, J = 19.0 Hz, 2H).

[0035] Due to the grafting of four 2,4-dinitrobenzenesulfonyl chloride (DNs) groups on 5,10,15,20-tetrakis(4-hydroxyphenyl)porphyrin (THPP), it will break and release sulfur dioxide gas simultaneously in the presence of glutathione (GSH). In order to study the GSH response characteristics of THPP-DNs, a sulfur dioxide gas molecular fluorescence probe 7-(diethylamino)coumarin (DEACA) was selected to quantitatively study the release of SO2 from it.

[0036] First, THPP-DNs was configured into aqueous solutions with different concentrations (50, 100, 200 μg / mL). After adding the same amount of 5 mM GSH solution and incubating for 1.5 h, 5 μM DEACA fluorescence probe was added. The solution was detected by a fluorescence spectrophotometer at different time points (1, 2, 3, 4, 6, 8, 10 h). It can be seen that with the increase of time, the release amount of SO2 increases, and at the same time, the higher the concentration, the more the release amount of SO2; after 10 hours of reaction, the concentration of SO2 released from 200 μg / mL THPP-DNs can reach 63.5 μM. As Figure 2 shown.

[0037] Example 2: The preparation method of nanoparticles formed by self-assembly of the photosensitizer molecule THPP-DNs and the tumor-targeting polymer FA-PEG-DSPE is as follows:

[0038] Dissolve 10 mg of THPP-DNs in 100 μL of tetrahydrofuran solution, stir at room temperature for 30 minutes, then dissolve 25 mg of phosphatidylethanolamine-polyethylene glycol-folic acid (FA-PEG-DSPE) in 2 mL of deionized water, add it dropwise to the above solution, and stir at room temperature for 24 hours. After dialysis with a dialysis bag with a molecular weight cut-off of 3000 for 48 hours, THPP-DNs@FA nanoparticles with tumor-targeting function are obtained.

[0039] Take 200 μL of THPP-DNs@FA nanoparticles and drop them into 1 mL of ethanol solution, mix well, then use a pipette to aspirate 5 μL of the well-mixed nanoparticle ethanol solution and drop it on the surface of a silicon wafer. Place the silicon wafer in an oven at 60 °C to dry. Characterize it using a scanning electron microscope, and it can be seen that the morphology of the self-assembled THPP-DNs@FA nanoparticles is spherical, with a particle size of about 40 - 50 nm. As Figure 3 shown.

[0040] Example 3: Fluorescence detection of sulfur dioxide release from the THPP-DNs@FA nanoparticles prepared in Example 2 at the cellular level was carried out as follows:

[0041] Inoculate human cervical cancer cells (HeLa cells) in a 6-well plate (5×10 4 cells / mL -1 , 2 mL per well), and culture them in an incubator at 37 °C and 5% CO2 for 24 h. Add PBS, THPP, and THPP-DNs@FA respectively, incubate the cells in the corresponding solutions for 4 h, then add 5 μL of the sulfur dioxide molecular fluorescence probe DEACA and incubate for 30 min. Then remove the culture medium and wash the cells 3 times with phosphate buffer. Finally, observe the cells through a fluorescence microscope.

[0042] The confocal laser scanning of PBS, THPP, and THPP-DNs@FA nanoparticles after incubation with HeLa cells and the sulfur dioxide molecular fluorescence probe DEACA for 30 min is as Figure 4 shown. There is no fluorescence in the culture wells of PBS and THPP, indicating that under normal conditions, HeLa cells do not produce sulfur dioxide gas molecules. However, very significant blue fluorescence is generated in the culture well with THPP-DNs@FA nanoparticles added, indicating that THPP-DNs@FA nanoparticles can react with overexpressed GSH in HeLa cells to release sulfur dioxide gas molecules.

[0043] Example 4: Detection of singlet oxygen ( 1 1O2) generated by THPP-DNs@FA nanoparticles under near-infrared light irradiation at the cellular level was carried out as follows:

[0044] Inoculate human cervical cancer cells (HeLa cells) in a 6-well plate (5×10 4 cells / mL -1 , 2 mL per well), and culture them in an incubator at 37 °C and 5% CO2 for 24 h. Add THPP and THPP-DNs@FA nanoparticles respectively, incubate the cells in the corresponding solutions for 4 h, add the singlet oxygen fluorescence probe SOSG (5 μL) and incubate for 30 min, and then irradiate with a 660 nm laser (0.5 W / cm 2)Irradiate for 5 minutes. Then remove the culture medium and wash the cells 3 times with phosphate-buffered saline. Finally, observe the cells under a fluorescence microscope.

[0045] It can be seen from Figure 5 that without laser irradiation, no fluorescence was observed in the HeLa cells treated with THPP and THPP-DNs@FA, indicating that neither of them can generate singlet oxygen under the condition of no laser irradiation. When irradiated with a 660 nm laser for 5 minutes, obvious green fluorescence was observed in the HeLa cells treated with THPP and THPP-DNs@FA, indicating the generation of singlet oxygen, proving that the THPP-DNs@FA nanoparticles prepared in the present invention can be used as a tumor photodynamic therapy agent for tumor photodynamic therapy.

[0046] Example 5: Evaluate the anti-tumor effect of THPP-DNs@FA nanoparticles at the cellular level as follows:

[0047] Incubate human cervical cancer cells (HeLa cells) in Dulbecco's modified Eagle's medium (DMEM). The medium contains 10% fetal bovine serum and 1% penicillin-streptomycin. Seed the HeLa cells into a 96-well plate (5×10 4 cells / mL -1 , 0.1 mL per well), and culture in an incubator at 37 °C and 5% CO2 for 24 h. Then co-culture the cells with THPP and THPP-DNs@FA therapeutic agents for 4 hours, and irradiate two of the groups with a 660 nm laser (0.5 W / cm 2 ) for 5 minutes. Use the MTT method to determine the survival rate of HeLa cells.

[0048] The results are as Figure 6As shown. It can be seen from the figure that without laser irradiation, the THPP photosensitizer does not produce obvious cytotoxicity to HeLa cells. Even at a concentration as high as 80 μg / mL, the cell survival rate still remains above 95%, indicating that the THPP photosensitizer molecule has good biocompatibility. Under external laser irradiation, the THPP photosensitizer molecule has an obvious killing effect on HeLa cells. This is because under 660 nm laser irradiation, THPP can generate singlet oxygen with high cytotoxicity in tumor cells, thereby killing tumor cells and realizing photodynamic therapy of tumors. Then, it can also be seen from the figure that single photodynamic therapy cannot kill all tumor cells, indicating that the effect of single photodynamic therapy is relatively limited. Without laser irradiation, the THPP-DNs@FA nanoparticles can also inhibit the survival of HeLa cells, mainly by reacting with GSH in tumor cells and releasing SO2 gas to kill tumor cells, thereby realizing gas therapy of tumors. Under external laser irradiation, the THPP-DNs@FA nanoparticles show excellent anti-tumor effects. At a concentration of 80 μg / mL, the THPP-DNs@FA nanoparticles can kill nearly 97% of HeLa cells. This is mainly because the THPP-DNs@FA nanoparticles combine two tumor treatment methods, photodynamic therapy and SO2 gas therapy, and achieve efficient treatment of tumor cells through the synergistic effect of the two.

[0049] Comparative Example 1: The rest are the same as in Example 1, except that:

[0050] 2,4-Dinitrobenzenesulfonyl chloride was replaced with p-toluenesulfonyl chloride, and the photosensitizer was prepared according to the following reaction formula:

[0051]

[0052] The results of the nuclear magnetic resonance hydrogen spectrum (room temperature, 400 MHz, DMSO-d6) of the product were as follows:

[0053] 1 1H NMR (400 MHz, DMSO) δ 7.84 (d, 2H), 7.75 (d, 8H), 7.48 (d, 8H), 7.35 (d, 4H), 7.17 (d, 4H), 6.76 (d, 8H), 6.44 (s, 2H), 6.38 (s, 2H), 6.24 (d, 2H), 2.43 (s, 12H).

[0054] Comparative Example 2: The rest are the same as in Example 1, except that:

[0055] 2,4-Dinitrobenzenesulfonyl chloride was replaced with 2,4-dimethylbenzenesulfonyl chloride, and the photosensitizer was prepared according to the following reaction formula:

[0056]

[0057] The results of the 1H NMR spectrum of the product (at room temperature, 400 MHz, DMSO-d6) were as follows:

[0058] 1 H NMR (400 MHz, DMSO) δ 7.84 (d, 2H), 7.70 (d, 4H), 7.42 (s, 4H), 7.34 - 7.35 (m, 8H), 7.17 (d, 4H), 6.76 (d, 8H), 6.44 (s, 2H), 6.38 (s, 2H), 6.24 (d, 2H), 2.64 (s, 12H), 2.43 (s, 12H).

[0059] Comparative Example 3: The rest was the same as in Example 1, except that:

[0060] 2,4-Dinitrobenzenesulfonyl chloride was replaced with 2-nitrobenzenesulfonyl chloride, and the photosensitizer was prepared according to the following reaction formula:

[0061]

[0062] The results of the 1H NMR spectrum of the product (at room temperature, 400 MHz, DMSO-d6) were as follows:

[0063] 1 H NMR (400 MHz, DMSO) δ 8.52 (d, 4H), 8.01 - 8.07 (m, 12H), 7.84 (d, 2H), 7.35 (d, 4H), 7.17 (d, 4H), 6.76 (d, 8H), 6.44 (s, 2H), 6.38 (s, 2H), 6.24 (d, 2H).

[0064] Comparative Example 4: The rest was the same as in Example 1, except that:

[0065] 2,4-Dinitrobenzenesulfonyl chloride was replaced with p-nitrobenzenesulfonyl chloride, and the photosensitizer was prepared according to the following reaction formula:

[0066]

[0067] The results of the 1H NMR spectrum of the product (at room temperature, 400 MHz, DMSO-d6) were as follows:

[0068] 11H NMR (400 MHz, DMSO) δ 8.48 (d, 8H), 8.09 (d, 8H), 7.84 (d, 2H), 7.35 (d, 4H), 7.17 (d, 4H), 6.76 (d, 8H), 6.44 (s, 2H), 6.38 (s, 2H), 6.24 (d, 2H)..

[0069] Comparative Example 5: The rest was the same as in Example 1, except that:

[0070] 2,4-Dinitrobenzenesulfonyl chloride was replaced with 3,4-dinitrobenzenesulfonyl chloride, and the photosensitizer was prepared according to the following reaction formula:

[0071]

[0072] The 1H nuclear magnetic resonance spectrum of the product (at room temperature, 400 MHz, DMSO-d6) was as follows:

[0073] 1 1H NMR (400 MHz, DMSO) δ 8.99 (s, 4H), 8.78 (d, 4H), 8.48 (d, 4H), 7.84 (d, 2H), 7.35 (d, 4H), 7.17 (d, 4H), 6.76 (d, 8H), 6.44 (s, 2H), 6.38 (s, 2H), 6.24 (d, 2H).

[0074] Comparative Example 6: The rest was the same as in Example 1, except that:

[0075] THPP was replaced with temoporfin, and the photosensitizer was prepared according to the following reaction formula:

[0076]

[0077] The 1H nuclear magnetic resonance spectrum of the product (at room temperature, 400 MHz, DMSO-d6) was as follows:

[0078] 1 1H NMR (400 MHz, DMSO) δ 9.05 (s, 4H), 8.87 (d, 4H), 8.32 (d, 4H), 7.84 (d, 2H), 7.35 (d, 4H), 7.17 (d, 4H), 6.76 (d, 8H), 6.44 (s, 2H), 6.38 (s, 2H), 6.24 (d, 2H).

[0079] The photosensitizer samples prepared in Example 1 and Comparative Examples 1-6 were respectively formulated into aqueous solutions with a concentration of 200 μg / mL. After adding the same amount of GSH solution with a concentration of 5 mM and incubating for 1.5 h, 5 μM of DEACA fluorescent probe was added. The solution was detected using a fluorescence spectrophotometer after 10 h, and the release amounts of SO2 of different photosensitizer samples were measured.

[0080] According to the method in Example 4, the fluorescence intensities of singlet oxygen in HeLa cells after treatment with the photosensitizer samples prepared in Example 1 and Comparative Examples 1-6 were measured respectively, and the results are as follows:

[0081] Table 1 Photodynamic therapy effects, release amounts of SO2 and anti-tumor effects of different photosensitizer samples

[0082] Group <![CDATA[Release amount of SO2 (μM)]]> Singlet oxygen fluorescence intensity (a.u.) Inhibition rate of HeLa cells (%) Example 1 63.5±2.1 14458 97.3±1.2 Comparative Example 1 23.9±1.7 14562 54.2±2.6 Comparative Example 2 18.1±3.8 14337 51.3±3.4 Comparative Example 3 17.6±3.2 14599 44.5±3.1 Comparative Example 4 15.8±1.3 14294 46.7±1.7 Comparative Example 5 22.2±2.9 14518 55.8±4.2 Comparative Example 6 24.8±2.6 14621 59.1±2.8

[0083] In Table 1, the release amounts of SO2 and the tumor cell inhibition rates of the photosensitizers in Comparative Examples 1-6 were significantly lower than those in Example 1, but the singlet oxygen generation abilities of these photosensitizers did not decrease significantly. Comparative Examples 1-2 showed that the efficient reaction of the sulfonate group in the photosensitizer molecule with GSH to generate SO2 depends on the substitution of the nitro group. When the nitro group was replaced with other alkyl groups, the reaction efficiency of the sulfonate group with GSH decreased significantly, resulting in insufficient release amount of SO2, and thus leading to a significant decrease in the killing effect on tumors. It can be seen that the nitro group is essential for the generation of SO2. Comparative Examples 3-5 showed that both the substitution site and the number of double nitro groups on the benzene ring would directly affect the reaction of the sulfonate group with GSH, resulting in a significant decrease in the release amount of SO2, and the killing effect of the photosensitizer on tumor cells also decreased significantly. Comparative Example 6 showed that selecting different photosensitizer parent molecules would result in different substitution sites of the sulfonate group on tetraphenylporphyrin, and the substitution site of the sulfonate group would also directly affect the efficient reaction of the sulfonate group with GSH to generate SO2. The wrong substitution site would lead to a sharp decrease in the release amount of SO2, and thus significantly reduce the killing effect of the photosensitizer on tumor cells.

Claims

1. A photosensitizer, characterized in that, The structural formula is as follows:

2. The preparation method of the photosensitizer according to claim 1, wherein It includes the following steps:

3. The preparation method of the photosensitizer according to claim 2, characterized in that, The base is triethylamine or diisopropylethylamine.

4. The preparation method of the photosensitizer according to claim 2, wherein, The molar ratio of the 5,10,15,20-tetra(4-hydroxyphenyl)porphyrin to 2,4-dinitrobenzenesulfonyl chloride is 1:3 - 8.

5. The preparation method of the photosensitizer according to claim 2, wherein The reaction steps of the 5,10,15,20-tetra(4-hydroxyphenyl)porphyrin and 2,4-dinitrobenzenesulfonyl chloride include: Dissolve 5,10,15,20-tetra(4-hydroxyphenyl)porphyrin in an organic solvent to obtain a first solution; dissolve 2,4-dinitrobenzenesulfonyl chloride in an organic solvent to obtain a second solution; add triethylamine to the first solution, stir in an ice-water bath, then add the second solution, and stir and react to obtain a photosensitizer molecule.

6. The preparation method of the photosensitizer according to claim 5, characterized in that, The organic solvent includes at least one of tetrahydrofuran, dimethyl sulfoxide, dimethylformamide, and dichloromethane.

7. Use of the photosensitizer according to claim 1 in the preparation of an anti-tumor drug.

8. The application according to claim 7, wherein It includes the following steps: Dissolve the photosensitizer in an organic solvent to obtain a third solution, dissolve phosphatidylethanolamine-polyethylene glycol-folic acid in water to obtain a fourth solution, drop the fourth solution into the third solution, stir and react at room temperature, and then dialyze to obtain an anti-tumor drug.

9. The application according to claim 8, characterized in that, The mass ratio of the photosensitizer to phosphatidylethanolamine-polyethylene glycol-folic acid is 1:2.5 - 3.

10. An anti-tumor nanoparticle, characterized in that, It includes a hydrophobic core and a hydrophilic outer shell wrapped around it. The hydrophobic core is the photosensitizer molecule according to claim 1; the hydrophilic outer shell is a folic acid-modified PEG long-chain molecule.

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