Photosensitizer PEG-In2O3 / Fe and its synthesis method and application

Abstract

The present invention discloses a photosensitizer PEG-In2O3 / Fe and its synthesis method and application. The synthesis method comprises the following steps: (1) adding InCl3 and FeCl3·6H2O to an ethanol aqueous solution, mixing with an ethanol ammonia aqueous solution and reacting in a water bath, centrifuging the precipitate obtained by the water bath reaction, washing with water, and drying to obtain an indium hydroxide precursor, and roasting to obtain In2O3 / Fe. (2) adding In2O3 / Fe to toluene, adding a chloroform solution containing PEG-SH after ultrasonic dispersion, and stirring evenly at room temperature; adding n-hexane and centrifuging, dispersing the precipitate obtained by centrifugation in an ethanol aqueous solution and centrifuging, dispersing the precipitate obtained by centrifugation in deionized water and centrifuging, and dispersing the precipitate obtained by centrifugation in water, ethanol or isopropanol to obtain a PEG-In2O3 / Fe solution. The photosensitizer of the present invention has high water solubility, strong photostability, high bioavailability, and can improve anti-tumor efficacy.

Description

Technical Field

[0001] The present application relates to the field of chemical technology, and in particular to a photosensitizer PEG-In2O3 / Fe and a synthesis method thereof, as well as an application of the photosensitizer PEG-In2O3 / Fe in photodynamic anti-tumor therapy. Background Art

[0002] Photodynamic therapy (PDT), a physical treatment for tumors, offers advantages such as non-invasiveness, minimal side effects, strong targeting, and high safety. PDT is a photocatalytic process that combines a photosensitizer, excitation light of a specific wavelength, and oxygen molecules. The specific wavelength of excitation light activates the photosensitizer within the body, generating cytotoxic reactive oxygen species in subcellular locations, initiating cell death pathways. Standard PDT relies on three key elements: the photosensitizer, excitation light, and oxygen molecules. Therefore, selecting a photosensitizer with good photoactivity and high safety is crucial for enhancing the efficacy of PDT.

[0003] Common photosensitizers are mainly divided into three generations: the first generation of photosensitizers are hematoporphyrin derivatives, which are composed of a complex mixture of water-soluble porphyrin monomers and oligomers. Hematoporphyrin derivatives have the disadvantages of unclear composition and poor penetration. The second generation of photosensitizers includes porphyrin compounds, metal phthalocyanines, condensed ring quinone compounds, etc. The second generation of photosensitizers has a clear structure and composition, enhanced penetration, and a wider range of applications. The third generation of photosensitizers is based on the second generation of photosensitizers and is combined with some biologically characteristic substances through some chemical bonds or other means. It can improve the targeting and utilization rate of photosensitizers and reduce the toxicity of photosensitizers. The photosensitizer activity of current photosensitizers still cannot meet the treatment needs and it is difficult to achieve the desired anti-tumor efficacy. Summary of the Invention

[0004] Based on this, given that the photosensitizers used in conventional technologies still lack the photoactivity to meet treatment needs and are unable to achieve adequate anti-tumor efficacy, it is necessary to provide a photosensitizer and a method for synthesizing a novel photosensitizer, PEG-In2O3 / Fe. The photosensitizer synthesized by the novel photosensitizer PEG-In2O3 / Fe method of the present invention has high water solubility, strong photoactivity, and high bioavailability, thereby improving anti-tumor efficacy.

[0005] An embodiment of the present application provides a method for synthesizing a novel photosensitizer PEG-In2O3 / Fe.

[0006] A method for synthesizing a novel photosensitizer PEG-In2O3 / Fe comprises the following steps:

[0007] (1) Synthesis of In2O3 / Fe

[0008] preparing an ethanol aqueous solution, adding InCl3 and FeCl3·6H2O to the ethanol aqueous solution, and stirring until completely dissolved to obtain a mixed solution, wherein the molar ratio of InCl3 and FeCl3·6H2O to Fe and In is 1:1 to 1:10 respectively;

[0009] Prepare ethanol ammonia solution;

[0010] The mixed solution is mixed with the ethanol ammonia solution and stirred at a predetermined temperature to react in a water bath, and then taken out and cooled to room temperature;

[0011] The precipitate obtained by the water bath reaction is centrifuged and washed with water;

[0012] The precipitate after centrifugal washing is dried to obtain a white indium hydroxide precursor;

[0013] calcining the indium hydroxide precursor to obtain light yellow In2O3 / Fe;

[0014] (2) Synthesis of PEG-In2O3 / Fe

[0015] Prepare a chloroform solution containing PEG-SH;

[0016] In2O3 / Fe was added to toluene, and after ultrasonic dispersion, the chloroform solution containing PEG-SH was added and stirred at room temperature;

[0017] Add n-hexane for the first centrifugation;

[0018] The precipitate obtained from the first centrifugation was dispersed in an ethanol-water solution and centrifuged a second time;

[0019] The precipitate obtained from the second centrifugation was dispersed in deionized water and centrifuged for the third time;

[0020] The precipitate obtained by the third centrifugation is dispersed in water, ethanol or isopropanol to obtain a PEG-In2O3 / Fe solution.

[0021] In some embodiments, the molar ratio of Fe to In includes 1:1, 1:2, 1:4, 1:8, and 1:10.

[0022] In some embodiments, the mixing of the mixed solution and the ethanol-ammonia aqueous solution and stirring the mixture at a predetermined temperature for reaction specifically includes the following steps:

[0023] The oil bath is preheated to a predetermined temperature, the mixed solution and the ethanol ammonia solution are mixed in the oil bath, and then stirred thoroughly to react in a water bath for at least 15 minutes, and then taken out and cooled to room temperature, wherein the predetermined temperature is not lower than 80°C.

[0024] In some embodiments, the precipitate obtained by the water bath reaction is centrifuged and washed with water, specifically comprising:

[0025] The precipitate obtained from the water bath reaction was divided into several portions and placed into centrifuge tubes, and then centrifuged and washed with water for at least 5 times.

[0026] In some embodiments, drying the precipitate after centrifugal washing specifically includes:

[0027] The precipitate after centrifugation and water washing was placed in a vacuum freeze drying box and dried for at least 8 h.

[0028] In some embodiments, calcining the indium hydroxide precursor specifically includes:

[0029] The indium hydroxide precursor is calcined in a tube furnace at a temperature of at least 250° C. for at least 3 hours by introducing air and nitrogen.

[0030] In some embodiments, the preparation of the chloroform solution containing PEG-SH specifically includes:

[0031] PEG-SH was weighed and added to chloroform to prepare a chloroform solution containing PEG-SH, wherein the mass volume ratio of PEG-SH to chloroform was 1:1 to 1:5 mg / mL, so that the concentration of PEG-SH in the chloroform solution containing PEG-SH was 1 mg / mL to 5 mg / mL.

[0032] In some embodiments, the mass volume ratio of In2O3 / Fe to toluene is 1:100 to 1:150 mg / μL.

[0033] In some embodiments, the synthesis method of the novel photosensitizer PEG-In2O3 / Fe further satisfies at least one of the following conditions:

[0034] (1) During the first centrifugation, the mass volume ratio of In2O3 / Fe to added n-hexane was 1:2-1:3 mg / mL;

[0035] (2) During the first centrifugation, centrifuge at no less than 10,000 rpm for at least 10 minutes;

[0036] (3) The second centrifugation comprises: dispersing the precipitate obtained from the first centrifugation in an ethanol-water solution, transferring the precipitate to a 1.5 mL centrifuge tube, and centrifuging the precipitate at no less than 14,000 rpm for at least 30 minutes;

[0037] (4) During the third centrifugation, the precipitate obtained from the second centrifugation is dispersed in deionized water and centrifuged at not less than 14,000 rpm for at least 20 minutes;

[0038] (5) Repeat the third centrifugation at least twice;

[0039] (6) The precipitate obtained from the third centrifugation was dispersed in 800 μL to 1200 μL of water, ethanol or isopropanol to obtain a PEG-In2O3 / Fe solution.

[0040] An embodiment of the present application also provides a photosensitizer PEG-In2O3 / Fe.

[0041] A photosensitizer PEG-In2O3 / Fe is prepared by adopting the synthesis method of the novel photosensitizer PEG-In2O3 / Fe.

[0042] An embodiment of the present application also provides an application of a photosensitizer PEG-In2O3 / Fe in photodynamic anti-tumor therapy.

[0043] The photosensitizer prepared by the above-mentioned novel photosensitizer PEG-In2O3 / Fe synthesis method has the following beneficial effects compared with photosensitizers in traditional technologies:

[0044] (1) By introducing iron into In2O3, the activity and stability of the material are further improved, and In2O3Fe can show a strong synergistic function in terms of physical and chemical properties or electrochemical properties. At the same time, the active chemical properties of iron are used to improve the overall oxidizability and chemical activity of the material, and the free Fe in the cell is reduced. 2+ Elevated levels can produce a large amount of ROS that damage cells through the Fenton reaction.

[0045] (2) Introducing the ferroptosis mechanism. Ferroptosis is an iron-dependent non-apoptotic cell death form, which is a process in which a large amount of reactive oxygen species (ROS) is produced in the presence of intracellular iron, accelerating lipid peroxidation and leading to cell death.

[0046] (3) By using PEG to encapsulate In2O3Fe, the dispersibility and water solubility of the photosensitizer are further improved, the bioavailability of the photosensitizer is increased, and the light responsiveness of the photosensitizer during PDT treatment is improved, thereby improving the anti-tumor efficacy. BRIEF DESCRIPTION OF THE DRAWINGS

[0047] To more clearly illustrate the technical solutions in the embodiments of the present application, the following briefly introduces the drawings required for describing the embodiments. Obviously, the drawings described below are only some embodiments of the present application. Those skilled in the art can also derive other drawings based on these drawings without inventive effort.

[0048] In order to more completely understand the present application and its beneficial effects, the following description will be given in conjunction with the accompanying drawings. In the following description, the same reference numerals represent the same parts.

[0049] Figure 1 Schematic diagram of scanning electron microscopy examination of In2O3, In2O3 / Fe, and PEG-In2O3 / Fe synthesized in Example 1 of the present invention;

[0050] Figure 2 Schematic diagram of the spectrum for detecting the production of active oxygen species by PEG-In2O3 / Fe synthesized in Example 1 of the present invention;

[0051] Figure 3 This is a schematic diagram showing the toxicity of PEG-In2O3 / Fe synthesized in Example 1 of the present invention to tumor cells in an MTT experiment;

[0052] Figure 4 This is a schematic diagram of the MTT experiment for detecting the toxicity of PEG-In2O3 / Fe to tumor cells when the PEG-In2O3 / Fe synthesized in Example 1 of the present invention is not irradiated;

[0053] Figure 5 Schematic diagram of the MTT experiment for detecting the phototoxicity of PEG-In2O3 / Fe to tumor cells when PEG-In2O3 / Fe synthesized in Example 1 of the present invention is exposed to light;

[0054] Figure 6 This is a schematic electrophoresis diagram of the expression levels of 4-HNE and ACSL4 in tumor cells after PDT treatment mediated by PEG-In2O3 / Fe synthesized in Example 1 of the present invention. DETAILED DESCRIPTION

[0055] To make the above-mentioned objects, features, and advantages of the present invention more readily apparent, specific embodiments of the present invention are described in detail below with reference to the accompanying drawings. The following description sets forth numerous specific details to facilitate a full understanding of the present invention. However, the present invention can be implemented in many other ways than those described herein, and those skilled in the art may make similar modifications without departing from the scope of the present invention. Therefore, the present invention is not limited to the specific embodiments disclosed below.

[0056] It should be noted that, in the description of the present invention, “several” means more than one, “many” means more than two, “greater than”, “less than”, “exceed”, etc. are understood as excluding the number itself, and “above”, “below”, “within”, etc. are understood as including the number itself.

[0057] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by those skilled in the art to which this invention pertains. The terms used herein in the specification of the present invention are for the purpose of describing specific embodiments only and are not intended to limit the present invention. The term "and / or" as used herein includes any and all combinations of one or more of the associated listed items.

[0058] The present invention provides a method for synthesizing a novel photosensitizer, PEG-In2O3 / Fe, to address the problem that the photosensitizers currently available do not have sufficient photoactivity to meet therapeutic needs and are unable to achieve adequate anti-tumor efficacy. The following describes the method for synthesizing the novel photosensitizer, PEG-In2O3 / Fe, in conjunction with the accompanying drawings.

[0059] The synthesis method of the novel photosensitizer PEG-In2O3 / Fe provided in the embodiments of the present application can be used for anti-tumor treatment, such as photodynamic therapy (PDT), a physical treatment method for tumors.

[0060] In order to more clearly illustrate the structure of the synthesis method of the new photosensitizer PEG-In2O3 / Fe, the synthesis method of the new photosensitizer PEG-In2O3 / Fe will be introduced below with reference to the accompanying drawings.

[0061] An embodiment of the present application provides a method for synthesizing a novel photosensitizer PEG-In2O3 / Fe.

[0062] A method for synthesizing a novel photosensitizer PEG-In2O3 / Fe comprises the following steps:

[0063] (1) Synthesis of In2O3 / Fe

[0064] An ethanol aqueous solution is prepared, InCl3 and FeCl3·6H2O are added to the ethanol aqueous solution, and stirred until completely dissolved to obtain a mixed solution, wherein the molar ratio of InCl3 and FeCl3·6H2O to Fe and In is 1:1 to 1:10 respectively;

[0065] Prepare ethanol ammonia solution;

[0066] The mixed solution is mixed with an ethanol-ammonia aqueous solution and stirred in a water bath at a predetermined temperature to react, and then taken out and cooled to room temperature;

[0067] The precipitate obtained by the water bath reaction is centrifuged and washed with water;

[0068] The precipitate after centrifugal washing is dried to obtain a white indium hydroxide precursor;

[0069] The indium hydroxide precursor is calcined to obtain light yellow In2O3 / Fe.

[0070] (2) Synthesis of PEG-In2O3 / Fe

[0071] Prepare a chloroform solution containing PEG-SH;

[0072] In2O3 / Fe was added to toluene, ultrasonically dispersed, and then chloroform solution containing PEG-SH was added and stirred at room temperature;

[0073] Add n-hexane for the first centrifugation;

[0074] The precipitate obtained from the first centrifugation was dispersed in an ethanol-water solution and centrifuged a second time;

[0075] The precipitate obtained from the second centrifugation was dispersed in deionized water and centrifuged for the third time;

[0076] The precipitate obtained by the third centrifugation is dispersed in water, ethanol or isopropanol to obtain a PEG-In2O3 / Fe solution.

[0077] In some embodiments, the volume ratio of ethanol to deionized water in the ethanol aqueous solution is 5:1 to 3:1.

[0078] In some embodiments, in the ethanol-ammonia aqueous solution, the volume ratio of ethanol to concentrated ammonia is 5:1 to 3:1.

[0079] In some embodiments, the molar ratio of Fe to In includes 1:1, 1:2, 1:4, 1:8, and 1:10.

[0080] In some embodiments, the mixed solution is mixed with an ethanol-ammonia aqueous solution and then stirred at a predetermined temperature for reaction, specifically comprising the following steps:

[0081] The oil bath is preheated to a predetermined temperature, the mixed solution is mixed with the ethanol ammonia solution, and then placed in the oil bath, stirred thoroughly, and reacted in a water bath for at least 15 minutes, then taken out and cooled to room temperature, wherein the predetermined temperature is not lower than 80°C.

[0082] In some embodiments, the precipitate obtained by the water bath reaction is centrifuged and washed with water, specifically comprising:

[0083] The precipitate obtained from the water bath reaction was divided into several portions and placed into centrifuge tubes, and then centrifuged and washed with water for at least 5 times.

[0084] In some embodiments, drying the precipitate after centrifugal washing specifically includes:

[0085] The precipitate after centrifugation and water washing was placed in a vacuum freeze drying box and dried for at least 8 h.

[0086] In some embodiments, calcining the indium hydroxide precursor specifically includes:

[0087] The indium hydroxide precursor is calcined in a tube furnace at a temperature of at least 250° C. for at least 3 hours by introducing air and nitrogen.

[0088] In some embodiments, the preparation of the chloroform solution containing PEG-SH specifically includes:

[0089] PEG-SH was weighed and added to chloroform to prepare a chloroform solution containing PEG-SH, wherein the mass volume ratio of PEG-SH to chloroform was 1:1 to 1:5 mg / mL, so that the concentration of PEG-SH in the chloroform solution containing PEG-SH was 1 mg / mL to 5 mg / mL.

[0090] In some embodiments, the mass volume ratio of In2O3 / Fe to toluene is 1:100 to 1:150 mg / μL.

[0091] In some embodiments, the synthesis method of the novel photosensitizer PEG-In2O3 / Fe further satisfies at least one of the following conditions:

[0092] (1) During the first centrifugation, the mass volume ratio of In2O3 / Fe to added n-hexane was 1:2-1:3 mg / mL;

[0093] (2) During the first centrifugation, centrifuge at no less than 10,000 rpm for at least 10 minutes;

[0094] (3) The second centrifugation comprises: dispersing the precipitate obtained from the first centrifugation in an ethanol-water solution, transferring the precipitate to a 1.5 mL centrifuge tube, and centrifuging the precipitate at no less than 14,000 rpm for at least 30 minutes;

[0095] (4) During the third centrifugation, the precipitate obtained from the second centrifugation is dispersed in deionized water and centrifuged at not less than 14,000 rpm for at least 20 minutes;

[0096] (5) Repeat the third centrifugation at least twice;

[0097] (6) The precipitate obtained from the third centrifugation was dispersed in 800 μL to 1200 μL of water, ethanol or isopropanol to obtain a PEG-In2O3 / Fe solution.

[0098] An embodiment of the present application also provides a photosensitizer.

[0099] A photosensitizer is prepared by adopting a synthesis method of a novel photosensitizer PEG-In2O3 / Fe.

[0100] An embodiment of the present application also provides an application of a photosensitizer PEG-In2O3 / Fe in photodynamic anti-tumor therapy.

[0101] Example 1

[0102] This embodiment provides a photosensitizer. The photosensitizer of this embodiment is prepared using the following synthesis method.

[0103] The synthesis method of the novel photosensitizer PEG-In2O3 / Fe of this embodiment comprises the following steps:

[0104] (1) Synthesis of In2O3 / Fe

[0105] Take 27 mL of ethanol and 9 mL of deionized water to prepare an ethanol aqueous solution, add InCl3 and FeCl3·6H2O to the ethanol aqueous solution, and stir until completely dissolved to obtain a mixed solution, wherein the molar ratio of InCl3 and FeCl3·6H2O satisfies Fe and In is 1:1.

[0106] Prepare an ethanol-ammonia solution by adding 27 mL of ethanol and 9 mL of concentrated ammonia water.

[0107] Preheat the oil bath to no less than 80°C, mix the mixed solution with the ethanol-ammonia solution, and then place it in the oil bath, stir thoroughly, and react in a water bath for at least 15 minutes. Then take it out and cool it to room temperature.

[0108] The precipitate obtained from the water bath reaction was divided into several portions and placed into centrifuge tubes, and then centrifuged and washed with water for at least 5 times.

[0109] The precipitate after centrifugal washing was placed in a vacuum freeze drying oven and dried for at least 8 hours to obtain a white indium hydroxide precursor;

[0110] The indium hydroxide precursor is calcined in a tube furnace at a temperature of at least 250° C. with air and nitrogen introduced therein for at least 3 hours to obtain light yellow In 2 O 3 / Fe.

[0111] (2) Synthesis of PEG-In2O3 / Fe

[0112] Weigh 2 mg of PEG-SH and add it to 2 mL of chloroform to prepare a chloroform solution containing 1 mg / mL PEG-SH.

[0113] 5.5 mg of In2O3 / Fe was added to 600 μL of toluene, and after ultrasonic dispersion, a chloroform solution containing PEG-SH was added and stirred at room temperature.

[0114] Then, 6 mL of n-hexane was added and the mixture was centrifuged for the first time at 10,000 rpm for 10 min.

[0115] The precipitate obtained from the first centrifugation was dispersed in ethanol aqueous solution, transferred to a 1.5 mL centrifuge tube, and centrifuged a second time at 14,000 rpm for 30 min.

[0116] The precipitate obtained from the second centrifugation was dispersed in deionized water and centrifuged for a third time at 14,000 rpm for 20 min. The third centrifugation was repeated twice.

[0117] The precipitate obtained by the third centrifugation was dispersed in 800 μL of water, ethanol or isopropanol to obtain a PEG-In 2 O 3 / Fe solution.

[0118] The results of ICP-OES testing are shown in Table 1, where In2O3 is represented by InO. The test proves that In2O3 / Fe and PEG-In2O3 / Fe were successfully synthesized in this embodiment.

[0119] Table 1

[0120]

[0121] The test results show that the mass ratio of iron to indium elements is 1:9.

[0122] Further quantitative calculations for the following experiment were performed: assuming 1g of iron and indium were encapsulated in PEG, with the combined mass of these two elements accounting for 72%. The combined mass of the compound of these two elements was 1.39g, and the mass of PEG was 1.24g. The mass ratio of In2O3 to PEG was In2O3:PEG = 1.12. The mass ratio of PEG to In2O3 was PEG:In2O3 = 0.9. It can be seen that for 1mg of In2O3 encapsulated in PEG, indium oxide accounts for 0.53mg and PEG accounts for 0.47mg. Using 10mg of In2O3 and 4mg of PEG, 6mg of the final photosensitizer, PEG-In2O3 / Fe, can be produced.

[0123] Example 2

[0124] The In2O3, In2O3 / Fe, and PEG-In2O3 / Fe synthesized in Example 1 were examined by scanning electron microscopy. Figure 1 The test results show that In2O3 was successfully synthesized, that the nanoscale size of the In2O3 / Fe material significantly increased after iron doping, and that the surface of the PEG-In2O3 / Fe material became smoother and the material size further increased after PEG was coated. These results demonstrate the successful synthesis of In2O3, In2O3 / Fe, and PEG-In2O3 / Fe.

[0125] Example 3

[0126] The PEG-In2O3 / Fe synthesized in Example 1 was subjected to an experiment to detect the production of reactive oxygen species. Methylene blue is a common dye that can be used to detect the production of reactive oxygen species (ROS). Detecting the production of reactive oxygen species is of great significance for studying the anti-tumor effect of materials. Detection principle: Based on the redox reaction produced by reactive oxygen species, under reducing conditions, the methyl group in the methylene blue molecule will be oxidized to formaldehyde by reactive oxygen species, and the phenyl ring in the methylene blue molecule will become colorless. Therefore, detecting the absorbance of methylene blue can reflect the amount of reactive oxygen species produced. See Figure 2 As shown, Figure 2 The horizontal axis is the wavelength, and the vertical axis is the absorption value. Figure 2 The five curves in the figure are, from top to bottom, control CT, PEG-In2O3 / Fe with a concentration of 0, PEG-In2O3 / Fe with a concentration of 25 μg / mL, PEG-In2O3 / Fe with a concentration of 50 μg / mL, and PEG-In2O3 / Fe with a concentration of 100 μg / mL.

[0127] Example 4

[0128] The toxicity of PEG-In2O3 / Fe synthesized in Example 1 to tumor cells was detected by MTT experiment (colorimetric method). 4T1 cells were seeded in a 96-well plate and incubated at 37°C and 5% CO2 for 24 hours. After incubation, the old culture medium was removed and protected from light. RPMI 1640 culture medium and PEG-In2O3 / Fe were added to the well plate respectively. After incubation at 37°C and 5% CO2 for 4 hours, serum was added and incubated for another 24 hours. Thiazolyl blue tetrazolium bromide solution (MTT, 5 mg / mL, 10 μL) was added to each well and incubated at 37°C and 5% CO2 for 4 hours. The supernatant was discarded and 150 μL dimethyl sulfoxide (DMSO) was added to each well. The absorbance at 570 nm was measured using an enzyme reader. The detection is as follows Figure 3 shown. Figure 3 The horizontal axis represents concentration, and the vertical axis represents cell activity. Analysis shows that the biocompatibility of PEG-In2O3 / Fe material on cells is normal within the range of 0 to 50 μg / mL, indicating that the material has good biocompatibility.

[0129] Example 5

[0130] The phototoxicity of PEG-In2O3 / Fe synthesized in Example 1 to tumor cells was detected by MTT assay. 4T1 cells were seeded in a 96-well plate and incubated at 37°C and 5% CO2 for 24 hours. After incubation, the old culture medium was removed and protected from light. RMPI 1640 culture medium and PEG-In2O3 / Fe were added to the plate respectively. After incubation at 37°C and 5% CO2 for 4 hours, the phototoxicity of the cells was detected by irradiation with a wavelength of 660 nm and 500 mW / cm 2 After 8 minutes of irradiation, the cells were incubated at 37°C in the dark for 24 hours. Thiazolyl blue tetrazolium bromide solution (MTT, 5 mg / mL, 10 μL) was added to each well. After incubation for 4 hours, 150 μL of DMSO was added to each well. The absorbance at 570 nm was measured using a microplate reader. The detection results are shown in Figure 2. Figure 4 、 Figure 5 As shown, Figure 4 、 5 In the equation, the horizontal axis is the concentration and the vertical axis is the cell activity. Figure 4 Not illuminated, Figure 5 Light treatment: Through analysis, it can be seen that the PDT mediated by PEG-In2O3 / Fe in this embodiment shows a significant killing effect on tumor cells.

[0131] Example 6

[0132] The biological efficacy of the PEG-In2O3 / Fe synthesized in Example 1 was verified. Western blotting experiments further verified the biological efficacy of the PEG-In2O3 / Fe material. Different components were separated by electrophoresis, and proteins were transferred ("printed") onto a specific membrane using blotting. The specific binding principle of antigen-antibody was then utilized, and antibodies were used as probes to detect target proteins in complex samples. This method was used to detect protein expression levels at different stages and protein interactions.

[0133] Tetrahydroxynonene (4-HNE), an aldehyde product of lipid peroxidation, regulates cell differentiation, proliferation, and apoptosis. Phospholipid hydroperoxide glutathione peroxidase (GPX4) is a key regulator of ferroptosis. Studies have shown that GPX4 expression is significantly elevated in tumor tissues compared to normal tissues. As a key factor in ferroptosis, loss of GPX4 function in non-small cell lung cancer, pancreatic cancer, prostate cancer, and melanoma cells can lead to persistent ferroptosis in vitro and reduce tumor recurrence in vivo. Long-chain acyl-CoA synthetase-4 (ACSL4) is involved in the biosynthesis and catabolism of fatty acids. ACSL4 catalyzes the synthesis of arachidonic acid (AA) into arachidonic acid-CoA and participates in the synthesis of membrane phospholipids. ACSL4 accumulates long-chain polyunsaturated ω6 fatty acids in cell membranes and determines ferroptosis sensitivity by shaping cellular lipid composition. Ferroptosis is closely related to the perturbation of iron-dependent lipid peroxides; these accumulated lipid reactive oxygen species can lead to cellular ferroptosis. Studies have found that ferroptosis inducers can inhibit tumor growth and kill cancer cells, making activating ferroptosis a new and effective cancer intervention pathway.

[0134] See also Figure 6 As shown, the results showed that after PEG-In2O3 / Fe-mediated PDT treatment, the expression levels of 4-HNE and ACSL4 in tumor cells were significantly increased, indicating that PEG-In2O3 / Fe-mediated PDT triggered ferroptosis of tumor cells.

[0135] In summary, the photosensitizer prepared by the synthesis method of the novel photosensitizer PEG-In2O3 / Fe of the present invention has the following beneficial effects compared with the photosensitizers in the traditional technology:

[0136] (1) By introducing iron into In2O3, the activity and stability of the material are further improved, and In2O3 / Fe can show a strong synergistic function in terms of physical and chemical properties or electrochemical properties. At the same time, the active chemical properties of iron are used to improve the overall oxidizability and chemical activity of the material, and the free Fe in the cell is reduced. 2+ Elevated levels can produce a large amount of ROS that damage cells through the Fenton reaction.

[0137] (2) Introducing the ferroptosis mechanism. Ferroptosis is an iron-dependent non-apoptotic cell death form, which is a process in which a large amount of reactive oxygen species (ROS) is produced in the presence of intracellular iron, accelerating lipid peroxidation and leading to cell death.

[0138] (3) By using PEG to encapsulate In2O3Fe, the dispersibility and water solubility of the photosensitizer are further improved, the bioavailability of the photosensitizer is increased, and the light responsiveness of the photosensitizer during PDT treatment is improved, thereby improving the anti-tumor efficacy.

[0139] In the above embodiments, the description of each embodiment has its own focus. For parts that are not described in detail in a certain embodiment, reference can be made to the relevant descriptions of other embodiments.

[0140] The technical features of the above-mentioned embodiments can be combined arbitrarily. In order to make the description concise, not all possible combinations of the technical features in the above-mentioned embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0141] The above-described embodiments merely illustrate several implementations of the present invention, and while their descriptions are relatively specific and detailed, they should not be construed as limiting the scope of the present invention. It should be noted that a person skilled in the art would be able to make numerous variations and improvements without departing from the spirit of the present invention, all of which fall within the scope of protection of the present invention. Therefore, the scope of protection of the present invention shall be determined by the appended claims.

Claims

1. A method for synthesizing a novel photosensitizer PEG-In2O3 / Fe, characterized in that: The steps include: (1) Synthesis of In2O3 / Fe preparing an ethanol aqueous solution, adding InCl3 and FeCl3·6H2O to the ethanol aqueous solution, and stirring until completely dissolved to obtain a mixed solution, wherein the molar ratio of InCl3 and FeCl3·6H2O to Fe and In is 1:1 to 1:10 respectively; Prepare ethanol ammonia solution; The mixed solution is mixed with the ethanol ammonia solution and stirred at a predetermined temperature to react in a water bath, and then taken out and cooled to room temperature; The precipitate obtained by the water bath reaction is centrifuged and washed with water; The precipitate after centrifugal washing is dried to obtain a white indium hydroxide precursor; calcining the indium hydroxide precursor to obtain light yellow In2O3 / Fe; (2) Synthesis of PEG-In2O3 / Fe Prepare a chloroform solution containing PEG-SH; In2O3 / Fe was added to toluene, and after ultrasonic dispersion, the chloroform solution containing PEG-SH was added and stirred at room temperature; Add n-hexane for the first centrifugation; The precipitate obtained from the first centrifugation was dispersed in an ethanol-water solution and centrifuged a second time; The precipitate obtained from the second centrifugation was dispersed in deionized water and centrifuged for the third time; The precipitate obtained by the third centrifugation is dispersed in water, ethanol or isopropanol to obtain a PEG-In2O3 / Fe solution.

2. The method for synthesizing the novel photosensitizer PEG-In2O3 / Fe according to claim 1, characterized in that: The molar ratios of Fe and In include 1:1, 1:2, 1:4, 1:8, and 1:

10.

3. The method for synthesizing the novel photosensitizer PEG-In2O3 / Fe according to claim 1, characterized in that: After the mixed solution and the ethanol-ammonia aqueous solution are mixed and stirred at a predetermined temperature for reaction, the method specifically comprises the following steps: The oil bath is preheated to a predetermined temperature, the mixed solution and the ethanol ammonia solution are mixed in the oil bath, and then stirred thoroughly to react in a water bath for at least 15 minutes, and then taken out and cooled to room temperature, wherein the predetermined temperature is not lower than 80°C.

4. The method for synthesizing the novel photosensitizer PEG-In2O3 / Fe according to claim 1, characterized in that: The synthesis method of the novel photosensitizer PEG-In2O3 / Fe also satisfies at least one of the following conditions: (1) When the precipitate obtained by the water bath reaction is centrifuged and washed with water, the method specifically includes: The precipitate obtained from the water bath reaction was divided into several portions and placed into centrifuge tubes, and then centrifuged and washed at least 5 times; (2) Drying the precipitate after centrifugal washing, specifically comprising: The precipitate after centrifugation and water washing was placed in a vacuum freeze drying box and dried for at least 8 h.

5. The method for synthesizing the novel photosensitizer PEG-In2O3 / Fe according to any one of claims 1 to 4, characterized in that: The indium hydroxide precursor is calcined, specifically comprising: The indium hydroxide precursor is calcined in a tube furnace at a temperature of at least 250° C. for at least 3 hours by introducing air and nitrogen.

6. The method for synthesizing the novel photosensitizer PEG-In2O3 / Fe according to any one of claims 1 to 4, characterized in that: The preparation of the chloroform solution containing PEG-SH specifically includes: PEG-SH was weighed and added to chloroform to prepare a chloroform solution containing PEG-SH, wherein the mass volume ratio of PEG-SH to chloroform was 1:1 to 1:5 mg / mL, so that the concentration of PEG-SH in the chloroform solution containing PEG-SH was 1 mg / mL to 5 mg / mL.

7. The method for synthesizing the novel photosensitizer PEG-In2O3 / Fe according to any one of claims 1 to 4, characterized in that: The mass volume ratio of In2O3 / Fe to toluene is 1:100~1:150mg / μL.

8. The method for synthesizing the novel photosensitizer PEG-In2O3 / Fe according to any one of claims 1 to 4, characterized in that: The synthesis method of the novel photosensitizer PEG-In2O3 / Fe also satisfies at least one of the following conditions: (1) During the first centrifugation, the mass volume ratio of In2O3 / Fe to added n-hexane was 1:2-1:3 mg / mL; (2) During the first centrifugation, centrifuge at no less than 10,000 rpm for at least 10 minutes; (3) The second centrifugation comprises: dispersing the precipitate obtained from the first centrifugation in an ethanol-water solution, transferring the precipitate to a 1.5 mL centrifuge tube, and centrifuging the precipitate at no less than 14,000 rpm for at least 30 minutes; (4) During the third centrifugation, the precipitate obtained from the second centrifugation is dispersed in deionized water and centrifuged at not less than 14,000 rpm for at least 20 minutes; (5) Repeat the third centrifugation at least twice; (6) The precipitate obtained from the third centrifugation was dispersed in 800 μL to 1200 μL of water, ethanol or isopropanol to obtain a PEG-In2O3 / Fe solution.

9. A photosensitizer PEG-In2O3 / Fe, characterized in that The novel photosensitizer PEG-In2O3 / Fe is prepared by the synthesis method according to any one of claims 1 to 8.

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