Preparation method and application of a ruthenium hydrogel drug delivery system

Abstract

This invention discloses a method for preparing a ruthenium hydrogel drug delivery system: PDA-IR780 nanocapsules are mixed with a ruthenium hydrogel solution and rapidly stirred, washed with distilled water, and freeze-dried to obtain the ruthenium hydrogel drug delivery system Ru(fmb)3-HAADH@PDA-IR780. The invention aims to improve drug targeting, enhance the pharmacokinetics of active ingredients, and integrate multiple therapeutic modalities to construct a photoresponsive ruthenium hydrogel drug delivery system. This system enhances the tumor-killing effect through combined photothermal and photodynamic therapy.

Description

Technical Field

[0001] This invention belongs to the field of drug delivery technology, specifically, it relates to a method for preparing and applying a ruthenium hydrogel drug delivery system. Background Technology

[0002] Hydrogels are a class of soft, biocompatible, three-dimensional (3D) porous materials capable of effectively encapsulating various types of active drugs, and have wide applications in tumor therapy, controlled drug release, cell carriers, tissue engineering, and biosensing. By locally injecting hydrogel drug delivery systems into / around tumors, the biotoxicity of conventional chemotherapy and radiotherapy can be improved, drug targeting can be enhanced, and the pharmacokinetics of active ingredients can be strengthened. Furthermore, multiple therapeutic modalities can be integrated simultaneously, thereby significantly improving cancer treatment outcomes.

[0003] Photoresponsive hydrogels have shown broad medical potential, enabling photothermal and photosensitive agents to be encapsulated within the hydrogel material itself or internally, triggering photothermal and photodynamic therapy (PDT) against tumor cells under light irradiation. This treatment offers advantages such as minimal adverse reactions, high specificity, and good reproducibility, demonstrating significant advantages over traditional tumor treatment methods. Among these, polydopamine nanoparticles (a photothermal agent) and the novel photosensitizer IR780 are widely used in photothermal and photodynamic therapy of tumors, respectively. They exert cytotoxic effects by generating reactive oxygen species or converting light energy into heat energy under light triggering, thereby killing tumor cells.

[0004] Ruthenium complexes have good biocompatibility and antitumor activity, and are recognized by the international pharmaceutical community as antitumor drugs with great development potential. Summary of the Invention

[0005] The purpose of this invention is to provide a method for preparing a ruthenium hydrogel drug delivery system.

[0006] Another object of the present invention is to provide the application of the ruthenium hydrogel drug delivery system prepared by the method described above in the preparation of antitumor drugs.

[0007] To achieve the above objectives, the technical solution adopted by the present invention is as follows:

[0008] In a first aspect, the present invention provides a method for preparing a ruthenium hydrogel drug delivery system, comprising the following steps:

[0009] The first step, the preparation method of polydopamine (PDA) nanocapsules, includes the following steps:

[0010] Ammonia and dimethyldiethoxysilane (DMDES) in a volume ratio of 1:1 are dissolved in ultrapure water, ultrasonically dispersed for 10-20 minutes (preferably 15 or 20 minutes), and allowed to stand for 2-8 hours (preferably 2 hours, 6 hours, or 8 hours) to obtain an emulsion mixture.

[0011] Dopamine hydrochloride was added to Tris buffer solution with pH = 8.5 and a concentration of 1-20 mmol / mL (10 mmol / mL). The molar ratio of dopamine hydrochloride to tris(hydroxymethyl)aminomethane (Tris) was 1:15. The mixture was then sonicated to obtain a homogeneous dispersion. The mixture was then added to the emulsion mixture at a volume ratio of 1:1. The mixture was sealed and stirred for 1-24 h (preferably 6 h, 12 h, or 24 h) at a temperature of 20-30°C (preferably 20 or 25°C).

[0012] Add an equal volume of anhydrous ethanol, sonicate for 1–10 minutes (preferably 2, 5, or 10 minutes), let stand at room temperature for 1–24 hours (preferably 8, 12, or 24 hours), centrifuge, remove the supernatant, resuspend the sample in anhydrous ethanol, and centrifuge again. Repeat this operation to resuspend and centrifuge at least three times. Resuspend the sample in ultrapure water, centrifuge again, and repeat this operation to resuspend and centrifuge at least three times. Wash with ultrapure water at least twice and then dry to obtain the polydopamine (PDA) nanocapsules.

[0013] The second step, the preparation method of polydopamine (PDA) composite IR780 nanocapsules (abbreviated as PDA-IR780 nanocapsules), includes the following steps:

[0014] A polydopamine (PDA) nanocapsule solution and an IR780 DMSO solution were mixed, with a PDA nanocapsule to IR780 mass ratio of 1 to 3:1 (preferably 1.7:1, 2:1, or 3.3:1). The mixture was stirred vigorously at room temperature for 1 to 24 hours (preferably 12 or 24 hours), followed by sonication. The supernatant was discarded, and the mixture was centrifuged. After removing the supernatant, the sample was resuspended in anhydrous ethanol and centrifuged again. This process of resuspension and centrifugation was repeated at least twice. The anhydrous ethanol was removed, and the sample was resuspended in ultrapure water and centrifuged again. This process of resuspension and centrifugation was repeated at least once. The mixture was then dried to obtain PDA-IR780 nanocapsules.

[0015] The third step, the preparation method of the ruthenium hydrogel drug delivery system Ru(fmb)3-HAADH@PDA-IR780, includes the following steps:

[0016] Ruthenium hydrogel (Ru(fmb)3-HAADH) was dissolved in distilled water to obtain a ruthenium hydrogel (Ru(fmb)3-HAADH) solution with a concentration of 5-50 mg / ml (preferably 15 or 25 mg / ml);

[0017] PDA-IR780 nanocapsules were mixed with a ruthenium hydrogel (Ru(fmb)3-HAADH) solution at a concentration of 5-30 mg / ml (preferably 15 mg / ml) and stirred rapidly. The mass ratio of PDA-IR780 nanocapsules to ruthenium hydrogel (Ru(fmb)3-HAADH) was 1:2-20 (preferably 1:6 or 1:10). The mixture was washed with distilled water and lyophilized to obtain the ruthenium hydrogel drug delivery system Ru(fmb)3-HAADH@PDA-IR780.

[0018] The PDA-IR780 nanocapsules have a particle size radius between 20 and 100 nm, exhibiting a good particle size distribution.

[0019] In the second step, the polydopamine (PDA) nanocapsules prepared in the first step are resuspended in water to a concentration of 0.5–3 mg / mL (preferably 1 mg / mL) to obtain a polydopamine (PDA) nanocapsule solution.

[0020] In the second step, IR780 is dissolved in DMSO to a concentration of 0.5–3 mg / mL (preferably 1 or 1.2 mg / mL) to obtain a DMSO solution of IR780.

[0021] In the second step, the ultrasound conditions are: 300W ultrasound for 5 minutes.

[0022] In the second step, the centrifugation conditions are: centrifugation at 13000 rpm for 15 min or 10 min.

[0023] The preparation method of the ruthenium hydrogel (Ru(fmb)3-HAADH) in the third step includes the following steps:

[0024] The hydrazide-modified hyaluronic acid solution was mixed with the polypyridine ruthenium metal complex Ru(fmb)3Cl2 solution and stirred rapidly. The mass ratio of hydrazide-modified hyaluronic acid to polypyridine ruthenium metal complex Ru(fmb)3Cl2 was 1-30:1 (preferably 11.9:1, 14.8:1, 19.8:1), and the stirring time was 1-3 min (preferably 2 min). The mixture was purified by dialysis and freeze-dried to obtain the metal ruthenium hydrogel (Ru(fmb)3-HAADH).

[0025] The preparation method of the hydrazide-modified hyaluronic acid solution includes the following steps:

[0026] Hydrated hyaluronic acid is dissolved in distilled water to obtain a hyaluronic acid solution with a concentration of 10-50 mg / mL (preferably 40 mg / mL).

[0027] The preparation method of the polypyridine ruthenium metal complex Ru(fmb)3Cl2 solution includes the following steps:

[0028] The polypyridine ruthenium metal complex Ru(fmb)3Cl2 was dissolved in distilled water to obtain a polypyridine ruthenium metal complex Ru(fmb)3Cl2 solution with a concentration of 1-5 mg / mL (preferably 2.025, 3.375, or 2.7 mg / mL).

[0029] The preparation method of the polypyridine ruthenium metal complex Ru(fmb)3Cl2 includes the following steps:

[0030] Under nitrogen protection, 4'-methyl-2,2'-bipyridine-4-carboxaldehyde was added to a Schlenk tube, dissolved in ethanol and water at a volume ratio of 2 to 8:1 (preferably 6:1), and then RuCl3·3H2O was added. The molar ratio of 4'-methyl-2,2'-bipyridine-4-carboxaldehyde to RuCl3·3H2O was 1 to 6:1 (preferably 3:1, 3.5:1, or 4.3:1). The mixture was heated under reflux for 2 to 24 hours (preferably 12 hours or 24 hours), cooled to room temperature, filtered, and the solution was evaporated to dryness to obtain the crude product. The crude product was dissolved in water and washed at least three times with excess dichloromethane. The product was then purified by neutral alumina column chromatography to obtain the polypyridine ruthenium metal complex Ru(fmb)3Cl2.

[0031] The preparation method of the hydrazide-modified hyaluronic acid (HAADH) includes the following steps:

[0032] Dissolve low molecular weight sodium hyaluronate in ultrapure water and stir until completely dissolved. Add adipic acid dihydrazide (ADH) at a mass ratio of 0.05–0.5:1 (preferably 0.12:1 or 0.24:1). Adjust the pH to 6.5–7 (preferably 6.8) with HCl or NaOH. Then slowly add 1-hydroxybenzotriazole (HOBt) and react for 15–60 min (preferably 30 min). Next, add 1-ethyl-(3-dimethylaminopropyl)carbodiimide (EDCi) and 1-hydroxybenzotriazole to the solution. The mass ratio of hydroxylamine (HOBt) to adipic acid dihydrazide (ADH) is 0.01–1:1 (preferably 0.05:1 or 0.1:1), and the mass ratio of 1-ethyl-(3-dimethylaminopropyl)carbodiimide (EDCi) to adipic acid dihydrazide (ADH) is 0.01–1:1 (preferably 0.07:1 or 0.14:1). The pH is adjusted to 6.5–7 with HCl or NaOH every half hour for 1–5 hours (preferably 4 hours). Then the mixture is stirred for 12–72 hours, purified by dialysis at least 3 times, and freeze-dried to obtain the hydrazide-modified hyaluronic acid (HAADH).

[0033] The low molecular weight sodium hyaluronate was purchased from Bloomage Biotechnology Co., Ltd., HA-TLM 20-40, MW = 200 kDa-400 kDa.

[0034] Another object of the present invention is to provide the application of the ruthenium hydrogel drug delivery system prepared by the method described above in the preparation of antitumor drugs.

[0035] The tumor was selected from melanoma.

[0036] By adopting the above technical solution, the present invention has the following advantages and beneficial effects:

[0037] The present invention provides a method for preparing a ruthenium hydrogel drug delivery system. The system uses polypyridine ruthenium as a metal matrix, crosslinked with hyaluronic acid modified with hydrazide to form a three-dimensional porous ruthenium hydrogel. By encapsulating polydopamine composite IR780 nanocapsules, it achieves photothermal and photodynamic therapy of tumors under photoresponsive conditions. The ruthenium hydrogel drug delivery system responds to the weakly acidic environment of the tumor, slowly dissociating and releasing the polydopamine active nanoparticles encapsulated within the gel, thus achieving photothermal and photodynamic therapy of tumors under light stimulation.

[0038] The present invention provides a method for preparing a ruthenium hydrogel drug delivery system, which is pH responsive. Its gel framework can intelligently respond to the weakly acidic environment inside the tumor, gradually dissociating and releasing the polydopamine active nanoparticles encapsulated within the gel, thereby achieving precise delivery of combined photothermal and photodynamic therapy to the tumor.

[0039] The present invention provides a method for preparing a ruthenium hydrogel drug-loading system. High-resolution scanning electron microscopy and rheological tests were performed on the ruthenium hydrogel drug-loading system prepared by this method. The results showed that the ruthenium hydrogel drug-loading system prepared by this invention has a uniform three-dimensional pore distribution, confirming the effective loading of nanoparticles and demonstrating that the ruthenium hydrogel drug-loading system possesses certain rheological properties, self-healing ability, and injectability. Dynamic light scattering and high-resolution transmission electron microscopy experiments showed that the nanoparticle size was between 50 and 100 nm, exhibiting good particle size distribution. UV-Vis absorption experiments confirmed that the ruthenium hydrogel drug-loading system achieves controlled release of photosensitizers in response to environmental pH. Photothermal experiments showed that the ruthenium hydrogel drug-loading system has good photothermal performance and reproducibility. Cellular ROS detection experiments showed that the ruthenium hydrogel drug-loading system can effectively generate reactive oxygen species, playing a role in killing cells.

[0040] The ruthenium hydrogel drug delivery system of the present invention can achieve photothermal and photodynamic combined therapy of tumors under light triggering, which enhances the killing effect on tumor cells and can respond to the weakly acidic environment of tumors to achieve targeted drug release, reduce the biotoxicity of traditional tumor treatments, and provide new ideas for clinical tumor treatment.

[0041] This drug delivery system focuses on improving the system's responsiveness and targeting.

[0042] The present invention aims to improve drug targeting, enhance the pharmacokinetics of active ingredients, and integrate multiple treatment methods to construct a photoresponsive ruthenium hydrogel drug delivery system, thereby improving the tumor-killing effect through combined photothermal and photodynamic therapy.

[0043] The ruthenium hydrogel drug delivery system of this invention is injectable and possesses photothermal and photodynamic properties, exhibiting photoresponsiveness, photothermal and photodynamic properties, and is injectable. The PDA-IR780 nanocapsules in the ruthenium hydrogel drug delivery system of this invention can achieve combined photothermal and photodynamic therapy of tumors under light triggering.

[0044] In this invention, the pH-responsive functional group is the acylhydrazone functional group generated during gel formation, which can slowly release the internal nanoparticles in the acidic environment of the tumor. Attached Figure Description

[0045] Figure 1 This is a schematic diagram of the synthetic route for a ruthenium hydrogel drug delivery system.

[0046] Figure 2 This is a scanning electron microscope (SEM) schematic diagram of a ruthenium hydrogel drug delivery system.

[0047] Figure 3 This is a schematic diagram of the rheological test of the Ru(fmb)3-HAADH@PDA-IR780 ruthenium hydrogel drug delivery system.

[0048] Figure 4 This is a high-resolution transmission electron microscope (TEM) schematic diagram of the PDA-IR780 nanocapsule.

[0049] Figure 5 This is a schematic diagram of the photothermal test results of the photoresponsive ruthenium hydrogel drug delivery system Ru(fmb)3-HAADH@PDA-IR780.

[0050] Figure 6 This is a schematic diagram of the reactive oxygen species detection results of the photoresponsive ruthenium hydrogel drug delivery system Ru(fmb)3-HAADH@PDA-IR780.

[0051] Figure 7This is a schematic diagram of the cytotoxicity test results for the Ru(fmb)3-HAADH@PDA-IR780 ruthenium hydrogel drug delivery system. Detailed Implementation

[0052] To more clearly illustrate the present invention, the following description, in conjunction with preferred embodiments, further clarifies the invention. Those skilled in the art should understand that the specific descriptions below are illustrative rather than restrictive, and should not be construed as limiting the scope of protection of the present invention.

[0053] Example 1

[0054] A method for preparing a ruthenium hydrogel drug delivery system includes the following steps:

[0055] Synthetic routes such as Figure 1 As shown, Figure 1 This is a schematic diagram of the synthetic route for a ruthenium hydrogel drug delivery system.

[0056] The first step, the preparation method of the polypyridine ruthenium metal complex Ru(fmb)3Cl2, includes the following steps:

[0057] Under nitrogen protection, 4'-methyl-2,2'-bipyridine-4-carboxaldehyde (7.5 mmol, 1.5 g) was added to a Schlenk tube, dissolved in 60 mL of ethanol and 10 mL of water, and then RuCl3·3H2O (1.75 mmol, 456 mg) was added. The mixture was heated under reflux for 24 h, cooled to room temperature, filtered, and the solution was evaporated to dryness to obtain a crude product, a brownish-black solid. The crude product was dissolved in 50 mL of water, washed three times with excess dichloromethane, and purified by neutral alumina column chromatography to obtain 614 mg of a reddish-brown solid, namely the polypyridine ruthenium metal complex Ru(fmb)3Cl2.

[0058] The second step, the preparation method of hydrazide-modified hyaluronic acid (HAADH), includes the following steps:

[0059] 1.2 g of low molecular weight sodium hyaluronate (Bloomage Biotechnology Co., Ltd., HA-TLM 20-40, MW = 200 kDa-400 kDa) was added to a round-bottom flask, followed by 120 mL of ultrapure water and stirring until completely dissolved. Adipic acid dihydrazide (ADH) (57.4 mmol, 10 g) was added, and the pH was adjusted to approximately 6.8 with 1 M NaOH aqueous solution. Then, 1-hydroxybenzotriazole (HOBt) (3.6 mmol, 486.5 mg) was slowly added, and the reaction was allowed to proceed for half an hour. Next, 1-ethyl-(3-dimethylaminopropyl)carbodiimide hydrochloride (EDCi) (4.5 mmol, 698.6 mg) was added to the solution. The pH was adjusted to approximately 6.8 with 1 M NaOH every half hour for 4 hours, followed by stirring overnight. The solution was purified by dialyzing three times the next day and then freeze-dried to obtain 1.4 g of hydrazide-modified hyaluronic acid (HAADH).

[0060] The third step, the preparation method of ruthenium hydrogel (Ru(fmb)3-HAADH), includes the following steps:

[0061] Hyaluronic acid hydrazide (HAADH) (1.2g) was dissolved in 30ml of distilled water to obtain a hyaluronic acid hydrazide solution with a concentration of 40mg / mL.

[0062] The polypyridine ruthenium metal complex Ru(fmb)3Cl2 (0.008 mmol, 5.4 mg) was dissolved in 2 mL of distilled water to obtain a polypyridine ruthenium metal complex Ru(fmb)3Cl2 solution with a concentration of 2.7 mg / mL.

[0063] 2 mL of a 40 mg / mL hydrazide-modified hyaluronic acid solution was mixed with 2 mL of a 2.7 mg / mL polypyridine ruthenium metal complex Ru(fmb)3Cl2 solution and stirred rapidly. A red gel-like substance was formed after 2 min. The red gel-like substance was purified by dialyzing three times and then freeze-dried to obtain 60 mg of ruthenium metal hydrogel (Ru(fmb)3-HAADH).

[0064] The fourth step, the preparation method of polydopamine (PDA) nanocapsules, includes the following steps:

[0065] The concentration of ammonia water is 25% (m / m), and the concentration of dimethyldiethoxysilane (DMDES) is 99% (m / m). 300 μL of ammonia water and 300 μL of dimethyldiethoxysilane (DMDES) are added to ultrapure water and brought to a final volume of 30 mL. The mixture is ultrasonically dispersed for 15 minutes and allowed to stand for 6 hours to obtain an emulsion mixture.

[0066] Tris(hydroxymethyl)aminomethane (Tris) was dissolved in ultrapure water and brought to a final volume of 30 mL with ultrapure water. The concentration of Tris(hydroxymethyl)aminomethane (Tris) was 10 mmol / mL, resulting in a Tris buffer solution with pH = 8.5 and a concentration of 10 mmol / mL.

[0067] Dopamine hydrochloride (20 mmol, 37 mg) was added to 30 mL of Tris buffer solution with pH = 8.5 and a concentration of 10 mmol / mL. The molar ratio of dopamine hydrochloride to tris(hydroxymethyl)aminomethane (Tris) was 1:15. The mixture was sonicated to obtain a homogeneous dispersion. The mixture was then added to the emulsion mixture at a volume ratio of 1:1. The mixture was sealed and stirred at 25°C for 24 h.

[0068] Add an equal volume of anhydrous ethanol, sonicate for 5 minutes, let stand at room temperature for 12 hours, centrifuge, remove the supernatant, resuspend the sample in anhydrous ethanol and centrifuge again. Repeat this operation for a total of three resuspensions and centrifugations. Resuspend the sample in ultrapure water and centrifuge again. Repeat this operation for a total of three resuspensions and centrifugations. Wash twice with ultrapure water and dry to obtain 20 mg polydopamine (PDA) nanocapsules.

[0069] Step 5, the preparation method of polydopamine (PDA) composite IR780 nanocapsules (abbreviated as PDA-IR780 nanocapsules), includes the following steps:

[0070] Polydopamine (PDA) nanocapsules were resuspended in water to a concentration of 1 mg / mL to obtain a polydopamine (PDA) nanocapsule solution.

[0071] Indogreen fluorescent probe IR780 (0.03 mmol, 20 mg) was dissolved in 20 mL of DMSO to obtain a concentration of 1 mg / mL, thus obtaining a DMSO solution of IR780.

[0072] 5 mL of a 1 mg / mL polydopamine (PDA) nanocapsule solution and 2.5 mL of a 1 mg / mL IR780 DMSO solution were mixed and stirred vigorously at room temperature for 24 h. The mixture was sonicated at 300 W for 5 min, the supernatant was discarded, and the mixture was transferred to a high-speed centrifuge tube and centrifuged at 13000 rpm for 15 min. After removing the supernatant, the sample was resuspended in 20 mL of anhydrous ethanol and centrifuged again at 13000 rpm for 10 min. This resuspension and centrifugation step was repeated twice. After removing the anhydrous ethanol, the sample was resuspended in 20 mL of ultrapure water, washed, and centrifuged again. This resuspension and centrifugation step was repeated once more. The sample was then dried to obtain 6.2 mg of PDA-IR780 nanocapsules.

[0073] Step 6, the preparation method of the ruthenium hydrogel drug delivery system Ru(fmb)3-HAADH@PDA-IR780, includes the following steps:

[0074] Dissolve 60 mg of the ruthenium hydrogel (Ru(fmb)3-HAADH) obtained in step 3 in 2 mL of distilled water to obtain a ruthenium hydrogel (Ru(fmb)3-HAADH) solution.

[0075] 5 mg of the PDA-IR780 nanocapsules obtained in step 5 were mixed with the above-mentioned ruthenium hydrogel (Ru(fmb)3-HAADH) solution and stirred rapidly. The mixture was washed three times with distilled water and lyophilized to obtain approximately 65 mg of the ruthenium hydrogel drug delivery system Ru(fmb)3-HAADH@PDA-IR780.

[0076] Example 2

[0077] A method for preparing a ruthenium hydrogel drug delivery system includes the following steps:

[0078] The first step, the preparation method of the polypyridine ruthenium metal complex Ru(fmb)3Cl2, includes the following steps:

[0079] Under nitrogen protection, 4'-methyl-2,2'-bipyridine-4-carboxaldehyde (5.25 mmol, 1.05 g) was added to a Schlenk tube, dissolved in 60 mL of ethanol and 10 mL of water, followed by the addition of RuCl3·3H2O (1.75 mmol, 456 mg). The mixture was heated under reflux for 12 h, cooled to room temperature, filtered, and the solution was evaporated to dryness to obtain a crude product, a brownish-black solid. The crude product was dissolved in 50 mL of water, washed three times with excess dichloromethane, and purified by neutral alumina column chromatography to obtain 509 mg of a reddish-brown solid, namely the polypyridine ruthenium metal complex Ru(fmb)3Cl2.

[0080] The second step, the preparation method of hydrazide-modified hyaluronic acid (HAADH), includes the following steps:

[0081] 1.2 g of low molecular weight sodium hyaluronate was added to a round-bottom flask, followed by 120 mL of ultrapure water and stirring until completely dissolved. Adipic acid dihydrazide (ADH) (28.7 mmol, 5 g) was added, and the pH was adjusted to approximately 6.8 with 1 M NaOH aqueous solution. Then, 1-hydroxybenzotriazole (HOBt) (3.6 mmol, 486.5 mg) was slowly added, and the reaction was allowed to proceed for half an hour. Next, 1-ethyl-(3-dimethylaminopropyl)carbodiimide hydrochloride (EDCi) (4.5 mmol, 698.6 mg) was added to the solution. The pH was adjusted to approximately 6.8 with 1 M NaOH every half hour for 4 hours, followed by stirring overnight. The solution was purified by dialyzing three times the next day and then freeze-dried to obtain 1.3 g of hydrazide-modified hyaluronic acid (HAADH).

[0082] The third step, the preparation method of ruthenium hydrogel (Ru(fmb)3-HAADH), includes the following steps:

[0083] Hyaluronic acid hydrazide (HAADH) (1.2g) was dissolved in 30ml of distilled water to obtain a hyaluronic acid hydrazide solution with a concentration of 40mg / mL.

[0084] The polypyridine ruthenium metal complex Ru(fmb)3Cl2 (0.006 mmol, 4.05 mg) was dissolved in 2 mL of distilled water to obtain a polypyridine ruthenium metal complex Ru(fmb)3Cl2 solution with a concentration of 2.025 mg / mL.

[0085] 2 mL of a 40 mg / mL hydrazide-modified hyaluronic acid solution was mixed with 2 mL of a 2.025 mg / mL polypyridine ruthenium metal complex Ru(fmb)3Cl2 solution and stirred rapidly. A red gel-like substance was formed after 2 min. The red gel-like substance was purified by dialyzing three times and then freeze-dried to obtain 55 mg of ruthenium metal hydrogel (Ru(fmb)3-HAADH).

[0086] The fourth step, the preparation method of polydopamine (PDA) nanocapsules, includes the following steps:

[0087] The concentration of ammonia water is 25% (m / m), and the concentration of dimethyldiethoxysilane (DMDES) is 99% (m / m). 300 μL of ammonia water and 300 μL of dimethyldiethoxysilane (DMDES) are added to ultrapure water and brought to a final volume of 30 mL. The mixture is ultrasonically dispersed for 10 minutes and allowed to stand for 2 hours to obtain an emulsion mixture.

[0088] Tris(hydroxymethyl)aminomethane (Tris) was dissolved in ultrapure water and brought to a final volume of 30 mL with ultrapure water. The concentration of Tris(hydroxymethyl)aminomethane (Tris) was 10 mmol / mL, resulting in a Tris buffer solution with pH = 8.5 and a concentration of 10 mmol / mL.

[0089] Dopamine hydrochloride (20 mmol, 37 mg) was added to 30 mL of Tris buffer solution with pH = 8.5 and a concentration of 10 mmol / mL. The molar ratio of dopamine hydrochloride to tris(hydroxymethyl)aminomethane (Tris) was 1:15. The mixture was sonicated to obtain a homogeneous dispersion. The mixture was then added to the emulsion mixture at a volume ratio of 1:1. The mixture was sealed and stirred at 20 °C for 12 h.

[0090] Add an equal volume of anhydrous ethanol, sonicate for 2 minutes, let stand at room temperature for 8 hours, centrifuge, remove the supernatant, resuspend the sample in anhydrous ethanol and centrifuge again. Repeat this operation for a total of three resuspensions and centrifugations. Resuspend the sample in ultrapure water and centrifuge again. Repeat this operation for a total of three resuspensions and centrifugations. Wash twice with ultrapure water and dry to obtain 15 mg polydopamine (PDA) nanocapsules.

[0091] Step 5, the preparation method of polydopamine (PDA) composite IR780 nanocapsules (abbreviated as PDA-IR780 nanocapsules), includes the following steps:

[0092] Polydopamine (PDA) nanocapsules were resuspended in water to a concentration of 1 mg / mL to obtain a polydopamine (PDA) nanocapsule solution.

[0093] Indogreen fluorescent probe IR780 (0.03 mmol, 20 mg) was dissolved in 20 mL of DMSO to obtain a concentration of 1 mg / mL, thus obtaining a DMSO solution of IR780.

[0094] 5 mL of a 1 mg / mL polydopamine (PDA) nanocapsule solution and 1.5 mL of a 1 mg / mL IR780 DMSO solution were mixed and stirred vigorously at room temperature for 12 h. The mixture was sonicated at 300 W for 5 min, the supernatant was discarded, and the mixture was transferred to a high-speed centrifuge tube and centrifuged at 13000 rpm for 15 min. After removing the supernatant, the sample was resuspended in 20 mL of anhydrous ethanol and centrifuged again at 13000 rpm for 10 min. This resuspension and centrifugation step was repeated twice. After removing the anhydrous ethanol, the sample was resuspended in 20 mL of ultrapure water, washed, and centrifuged again. This resuspension and centrifugation step was repeated once more. The sample was then dried to obtain 5.6 mg of PDA-IR780 nanocapsules.

[0095] Step 6, the preparation method of the ruthenium hydrogel drug delivery system Ru(fmb)3-HAADH@PDA-IR780, includes the following steps:

[0096] Dissolve 30 mg of the ruthenium hydrogel (Ru(fmb)3-HAADH) obtained in step 3 in 2 mL of distilled water to obtain a ruthenium hydrogel (Ru(fmb)3-HAADH) solution.

[0097] 5 mg of the PDA-IR780 nanocapsules obtained in step 5 were mixed with the above-mentioned ruthenium hydrogel (Ru(fmb)3-HAADH) solution and stirred rapidly. The mixture was washed three times with distilled water and lyophilized to obtain approximately 33 mg of the ruthenium hydrogel drug delivery system Ru(fmb)3-HAADH@PDA-IR780.

[0098] Example 3

[0099] A method for preparing a ruthenium hydrogel drug delivery system includes the following steps:

[0100] The first step, the preparation method of the polypyridine ruthenium metal complex Ru(fmb)3Cl2, includes the following steps:

[0101] Under nitrogen protection, 4'-methyl-2,2'-bipyridine-4-carboxaldehyde (6.2 mmol, 1.2 g) was added to a Schlenk tube, dissolved in 60 mL of ethanol and 10 mL of water, and then RuCl3·3H2O (1.75 mmol, 456 mg) was added. The mixture was heated under reflux for 12 h, cooled to room temperature, filtered, and the solution was evaporated to dryness to obtain a crude product, a brownish-black solid. The crude product was dissolved in 50 mL of water, washed three times with excess dichloromethane, and purified by neutral alumina column chromatography to obtain 572 mg of a reddish-brown solid, namely the polypyridine ruthenium metal complex Ru(fmb)3Cl2.

[0102] The second step, the preparation method of hydrazide-modified hyaluronic acid (HAADH), includes the following steps:

[0103] 1.2 g of low molecular weight sodium hyaluronate was added to a round-bottom flask, followed by 120 mL of ultrapure water and stirring until completely dissolved. Adipic acid dihydrazide (ADH) (57.4 mmol, 10 g) was added, and the pH was adjusted to approximately 6.8 with 1 M NaOH aqueous solution. Then, 1-hydroxybenzotriazole (HOBt) (3.6 mmol, 486.5 mg) was slowly added, and the reaction was allowed to proceed for half an hour. Next, 1-ethyl-(3-dimethylaminopropyl)carbodiimide hydrochloride (EDCi) (4.5 mmol, 698.6 mg) was added to the solution. The pH was adjusted to approximately 6.8 with 1 M NaOH every half hour for 4 hours, and the reaction was continued with stirring for 48 hours. The solution was then purified by dialyzing three times and freeze-dried to obtain 1.5 g of hydrazide-modified hyaluronic acid (HAADH).

[0104] The third step, the preparation method of ruthenium hydrogel (Ru(fmb)3-HAADH), includes the following steps:

[0105] Hyaluronic acid hydrazide (HAADH) (1.2g) was dissolved in 30ml of distilled water to obtain a hyaluronic acid hydrazide solution with a concentration of 40mg / mL.

[0106] The polypyridine ruthenium metal complex Ru(fmb)3Cl2 (0.01 mmol, 6.75 mg) was dissolved in 2 mL of distilled water to obtain a polypyridine ruthenium metal complex Ru(fmb)3Cl2 solution with a concentration of 3.375 mg / mL.

[0107] 2 mL of a 40 mg / mL hydrazide-modified hyaluronic acid solution was mixed with 2 mL of a 3.375 mg / mL polypyridine ruthenium metal complex Ru(fmb)3Cl2 solution and stirred rapidly. A red gel-like substance was formed after 2 min. The red gel-like substance was purified by dialyzing three times and then freeze-dried to obtain 63 mg of ruthenium metal hydrogel (Ru(fmb)3-HAADH).

[0108] The fourth step, the preparation method of polydopamine (PDA) nanocapsules, includes the following steps:

[0109] The concentration of ammonia water is 25% (m / m), and the concentration of dimethyldiethoxysilane (DMDES) is 99% (m / m). 300 μL of ammonia water and 300 μL of dimethyldiethoxysilane (DMDES) are added to ultrapure water and brought to a final volume of 30 mL. The mixture is ultrasonically dispersed for 20 minutes and allowed to stand for 8 hours to obtain an emulsion mixture.

[0110] Tris(hydroxymethyl)aminomethane (Tris) was dissolved in ultrapure water and brought to a final volume of 30 mL with ultrapure water. The concentration of Tris(hydroxymethyl)aminomethane (Tris) was 10 mmol / mL, resulting in a Tris buffer solution with pH = 8.5 and a concentration of 10 mmol / mL.

[0111] Dopamine hydrochloride (20 mmol, 37 mg) was added to 30 mL of Tris buffer solution with pH = 8.5 and a concentration of 10 mmol / mL. The molar ratio of dopamine hydrochloride to tris(hydroxymethyl)aminomethane (Tris) was 1:15. The mixture was sonicated to obtain a homogeneous dispersion. The mixture was then added to the emulsion mixture at a volume ratio of 1:1. The mixture was sealed and stirred at 25°C for 6 h.

[0112] Add an equal volume of anhydrous ethanol, sonicate for 10 minutes, let stand at room temperature for 24 hours, centrifuge, remove the supernatant, resuspend the sample in anhydrous ethanol and centrifuge again. Repeat this operation for a total of three resuspensions and centrifugations. Resuspend the sample in ultrapure water and centrifuge again. Repeat this operation for a total of three resuspensions and centrifugations. Wash twice with ultrapure water and dry to obtain 13 mg polydopamine (PDA) nanocapsules.

[0113] Step 5, the preparation method of polydopamine (PDA) composite IR780 nanocapsules (abbreviated as PDA-IR780 nanocapsules), includes the following steps:

[0114] Polydopamine (PDA) nanocapsules were resuspended in water to a concentration of 1 mg / mL to obtain a polydopamine (PDA) nanocapsule solution.

[0115] Indogreen fluorescent probe IR780 (0.036 mmol, 24 mg) was dissolved in 20 mL of DMSO to obtain a concentration of 1.2 mg / mL, thus obtaining a DMSO solution of IR780.

[0116] 5 mL of a 1 mg / mL polydopamine (PDA) nanocapsule solution and 2.5 mL of a 1.2 mg / mL IR780 DMSO solution were mixed and stirred vigorously at room temperature for 24 h. The mixture was then sonicated at 300 W for 5 min, the supernatant was discarded, and the mixture was transferred to a high-speed centrifuge tube. The mixture was centrifuged at 8000 rpm for 15 min, the supernatant was removed, and the sample was resuspended in 20 mL of anhydrous ethanol and centrifuged again at 8000 rpm for 10 min. This resuspension and centrifugation step was repeated twice. After removing the anhydrous ethanol, the sample was resuspended in 20 mL of ultrapure water, washed, and centrifuged again. This resuspension and centrifugation step was repeated once more. Finally, the sample was dried to obtain 5.2 mg of PDA-IR780 nanocapsules.

[0117] Step 6, the preparation method of the ruthenium hydrogel drug delivery system Ru(fmb)3-HAADH@PDA-IR780, includes the following steps:

[0118] Dissolve 50 mg of the ruthenium hydrogel (Ru(fmb)3-HAADH) obtained in step 3 in 2 mL of distilled water to obtain a ruthenium hydrogel (Ru(fmb)3-HAADH) solution.

[0119] 5 mg of the PDA-IR780 nanocapsules obtained in step 5 were mixed with the above-mentioned ruthenium hydrogel (Ru(fmb)3-HAADH) solution and stirred rapidly. The mixture was washed three times with distilled water and lyophilized to obtain approximately 55 mg of the ruthenium hydrogel drug delivery system Ru(fmb)3-HAADH@PDA-IR780.

[0120] Example 4

[0121] Scanning electron microscopy and rheological characterization

[0122] The ruthenium hydrogel drug delivery system Ru(fmb)3-HAADH@PDA-IR780 prepared in Example 1 was observed by high-resolution scanning electron microscopy (SEM), and the results are as follows: Figure 2 As shown, Figure 2 The images show SEM images of the ruthenium hydrogel drug delivery system. (i) shows the SEM morphology of Ru(fmb)3-HAADH at a scale of 500 μm; (ii) shows the SEM morphology of Ru(fmb)3-HAADH at a scale of 50 μm; (iii) shows the SEM morphology of the Ru(fmb)3-HAADH@PDA-IR780 ruthenium hydrogel drug delivery system at a scale of 500 μm; and (iv) shows the SEM morphology of the Ru(fmb)3-HAADH@PDA-IR780 ruthenium hydrogel drug delivery system at a scale of 50 μm. It is evident that the ruthenium hydrogel (Ru(fmb)3-HAADH) has a three-dimensional network structure, and after loading PDA@IR780 nanocapsules, the pores of the ruthenium hydrogel drug delivery system Ru(fmb)3-HAADH@PDA-IR780 show significant morphological changes and become rougher.

[0123] Rheological test results as follows Figure 3 As shown, Figure 3 This is a schematic diagram of the rheological testing of the ruthenium hydrogel drug delivery system Ru(fmb)3-HAADH@PDA-IR780. In the diagram, a is a schematic diagram of the rheological curve of the ruthenium hydrogel drug delivery system Ru(fmb)3-HAADH@PDA-IR780, b is a schematic diagram of the strain scan curve of the ruthenium hydrogel drug delivery system Ru(fmb)3-HAADH@PDA-IR780, c is a schematic diagram of the continuous step strain curve of the ruthenium hydrogel drug delivery system Ru(fmb)3-HAADH@PDA-IR780, and d is a schematic diagram of the thixotropic curve of the ruthenium hydrogel drug delivery system Ru(fmb)3-HAADH@PDA-IR780. As shown in the figure, the strain scanning curves indicate that the modulus of the ruthenium hydrogel drug-loaded system Ru(fmb)3-HAADH@PDA-IR780 changes under high stress, indicating that Ru(fmb)3-HAADH@PDA-IR780 possesses high mechanical strength. Both the continuous step strain curve and the thixotropic curve reflect that the viscosity of Ru(fmb)3-HAADH@PDA-IR780 decreases and its fluidity increases after being subjected to shear stress. However, after the shear stress is removed, the material gradually returns to its original high viscosity state, indicating that Ru(fmb)3-HAADH@PDA-IR780 has good self-healing properties. Ruthenium hydrogels exhibit excellent rheological characteristics and self-healing properties.

[0124] The PDA-IR780 nanocapsules prepared in Example 1 were observed using a high-resolution scanning electron microscope (SEM), and the results are as follows: Figure 4As shown, Figure 4 This is a high-resolution transmission electron microscope (TEM) schematic diagram of the PDA-IR780 nanocapsules. The image shows that the PDA-IR780 nanocapsules have a diameter of 41.77 nm and a particle radius between 20 and 100 nm.

[0125] Example 5

[0126] Photothermal performance experiment

[0127] The ruthenium hydrogel drug delivery system Ru(fmb)3-HAADH@PDA-IR780 prepared in Example 1 was diluted to PBS solutions of 200 ug / mL, 500 ug / mL, 750 ug / mL, 1000 ug / mL, 1500 ug / mL, and 2000 ug / mL (PDA nanocapsule concentrations), respectively. The PBS solution was used as a blank control. The solutions were analyzed at a wavelength λ = 808 nm and a power density P = 1.5 W / cm². 2 The solution was irradiated with a laser for 540 seconds, and its heating process was monitored and a heating curve was plotted. The results are as follows: Figure 5 As shown in (i), Figure 5 The diagram shows the photothermal test results of the photoresponsive ruthenium hydrogel drug delivery system Ru(fmb)3-HAADH@PDA-IR780. Analysis of (i) shows that, with a fixed light power, as the concentration of Ru(fmb)3-HAADH@PDA-IR780 increases, the concentration of PDA nanocapsules in the system also increases, resulting in a stronger heating capacity. When the concentration of PDA nanocapsules in Ru(fmb)3-HAADH@PDA-IR780 reaches 1500 μg / mL, the heating capacity essentially reaches saturation and no longer increases with the increase of PDA nanocapsule concentration.

[0128] With wavelength λ = 808 nm and power density P = 1.5 W / cm², respectively... 2 2.0W / cm 2 2.5W / cm 2 3.0W / cm 2 The 1000 μg / mL ruthenium hydrogel drug delivery system Ru(fmb)3-HAADH@PDA-IR780 was irradiated with a laser for 540 s, and its heating process was monitored and a heating curve was plotted. The results are as follows: Figure 5As shown in (ii), the analysis in (ii) shows that the laser irradiation power can greatly affect the photothermal heating of the Ru(fmb)3-HAADH@PDA-IR780 metal ruthenium hydrogel drug delivery system. The heating capacity increases with the increase of power, but in actual use, it is not advisable to use lasers with excessive power to avoid burns to the skin and other tissues.

[0129] With a wavelength λ = 808 nm and a power density P = 1.5 W / cm², 2 A 1000 μg / mL system was irradiated with laser light for 240 s, then allowed to cool naturally at room temperature. This irradiation-cooling process was repeated, and temperature changes were monitored. Heating curves were plotted to investigate the photothermal elasticity of the ruthenium hydrogel drug delivery system Ru(fmb)3-HAADH@PDA-IR780. The results are as follows: Figure 5 As shown in (iii), the analysis in (iii) shows that this gel system has photothermal elasticity and can maintain excellent photothermal performance after repeated photothermal heating and cooling. It can be repeatedly irradiated within the service cycle without repeated injection, thus improving biosafety.

[0130] Figure 5 The results of in vitro photothermal imaging (iv) and (v) were obtained by taking 2 mL of PBS, polydopamine (PDA) nanocapsule solution (PDA shown in the figure) (1000 μg / mL), IR780 DMSO solution (IR780 shown in the figure) (500 μg / mL), ruthenium hydrogel (Ru(fmb)3-HAADH) solution (Ru(fmb)3-HAADH shown in the figure) (2000 μg / mL), PDA-IR780 nanocapsule solution (PDA@IR780 shown in the figure) (1000 μg / mL, 500 μg / mL), and ruthenium hydrogel drug delivery system Ru(fmb)3-HAADH@PDA-IR780 (Ru(fmb)3-HAADH@PDA-IR780 shown in the figure) (2000 μg / mL, 1000 μg / mL, 500 μg / mL) in a quartz cuvette. At the same PDA-IR780 nanocapsule solution concentration, the ruthenium hydrogel drug delivery system Ru(fmb)3-HAADH@PDA-IR780 exhibited the strongest photothermal performance, with a temperature rise of 24.5℃ within 2 minutes after light irradiation, compared to 22.9℃ for the PDA-IR780 system. These results demonstrate that the prepared ruthenium hydrogel drug delivery system Ru(fmb)3-HAADH@PDA-IR780 possesses excellent photothermal effects and superior photothermal elasticity, allowing for repeated heating and cooling.

[0131] Example 6

[0132] Intracellular reactive oxygen species (ROS) detection of the ruthenium hydrogel drug delivery system Ru(fmb)3-HAADH@PDA-IR780 prepared in Example 1

[0133] Mouse melanoma cells were selected, specifically B16F10 cells in the logarithmic growth phase, and the cells were concentrated at a concentration of 10-1. 5 / mL was seeded into a confocal culture dish and cultured for 24 h. The culture medium was discarded, and free IR780, PDA-IR780 nanocapsules, and the ruthenium hydrogel drug delivery system Ru(fmb)3-HAADH@PDA-IR780 prepared in Example 1 were added to each well. A blank cell group was also set up, for a total of four groups. After culturing in the dark for another 24 h, the culture medium was discarded, and the cells were washed three times with PBS to remove untaken drugs. 2 mL of 2',7'-dichlorodihydrofluorescein diacetic acid (DCFH-DA) reactive oxygen species detection probe (DCFH-DA: culture medium 3:1000) was added to each well, and the probe was used at a wavelength λ = 808 nm and a power density P = 1.5 W / cm². 2 Irradiate with laser for 120 seconds. After incubation for another 20 minutes, wash away excess staining probes with PBS and observe the staining using a confocal microscope.

[0134] Test results as follows Figure 6 As shown, Figure 6 This is a schematic diagram illustrating the reactive oxygen species (ROS) detection results of the photoresponsive ruthenium hydrogel drug delivery system Ru(fmb)3-HAADH@PDA-IR780. As shown in the figure, the intracellular ROS content in the Ru(fmb)3-HAADH@PDA-IR780-illuminated group was significantly higher than that in the free IR780-illuminated group and the group containing nanocapsules generated by the PDA-IR780-illuminated group. Furthermore, at pH 5.5, the intracellular ROS content after Ru(fmb)3-HAADH@PDA-IR780 illumination was higher than that after illumination at pH 7.4, demonstrating that the Ru(fmb)3-HAADH@PDA-IR780-illuminated drug delivery system possesses strong oxygen-enhancing capabilities and releases the encapsulated drug more rapidly in a weakly acidic environment.

[0135] Example 7

[0136] Cytotoxicity assay of the ruthenium hydrogel drug delivery system Ru(fmb)3-HAADH@PDA-IR780 prepared in Example 1

[0137] Mouse melanoma cells were selected, specifically B16F10 cells in the logarithmic growth phase, and the cells were concentrated at a concentration of 1×10⁻⁶. 4Four 96-well plates were inoculated with Ru(fmb)3-HAADH@PDA-IR780 nanocapsules per well. After 24 hours of incubation, the culture medium was discarded. Five replicate groups were established: Ru(fmb)3-HAADH@PDA-IR780 under light, Ru(fmb)3-HAADH@PDA-IR780 in the dark, PDA-IR780 nanocapsule under light, PDA-IR780 nanocapsule in the dark, and free IR780 under light. Different concentration gradients were added, equivalent to photosensitizer concentrations of 50 μg / mL, 25 μg / mL, 12.5 μg / mL, 6.25 μg / mL, 3.13 μg / mL, 1.56 μg / mL, 0.78 μg / mL, and 0 μg / mL. Each gradient was repeated in six replicates. The plates were incubated in the dark for 24 hours. The culture medium was discarded, the plates were washed three times with PBS, and 100 μL of complete culture medium was added. The light-treated groups were incubated at a wavelength of λ = 808 nm and a power density of P = 1.5 W / cm². 2 After 120 seconds of laser irradiation, the samples were cultured in the dark for 24 hours. The dark-protected group was washed three times with PBS, and 100 μL of complete culture medium was added before further culture for 24 hours. Both groups were then added 100 μL of serum-free culture medium containing 10% CCK-8 and cultured in the dark for another 2 hours. The absorbance of each well at 450 nm was measured using a microplate reader.

[0138] Cytotoxicity test results as follows Figure 7 As shown, Figure 7 This is a schematic diagram illustrating the cytotoxicity assay results of the Ru(fmb)3-HAADH@PDA-IR780 ruthenium hydrogel drug delivery system. The figure shows the median lethal concentration (IC50) of Ru(fmb)3-HAADH@PDA-IR780 under light irradiation. 50 The value is significantly higher than that of the Ru(fmb)3-HAADH@PDA-IR780 light-shielding group IC. 50 The lower value indicates that the gel system in the Ru(fmb)3-HAADH@PDA-IR780 light irradiation group has a stronger killing effect on tumors; at the same time, the Ru(fmb)3-HAADH@PDA-IR780 light irradiation group has a stronger killing effect than the PDA@IR780 light irradiation group, indicating that the Ru(II) ligand released by the Ru(fmb)3-HAADH@PDA-IR780 gel has a killing effect on tumors.

[0139] The ruthenium hydrogel drug delivery system Ru(fmb)3-HAADH@PDA-IR780 prepared in this embodiment of the invention exhibits significantly better tumor cell killing effects than free IR780 and also significantly better than PDA-IR780 nanocapsules. This indicates that the ruthenium hydrogel drug delivery system Ru(fmb)3-HAADH@PDA-IR780 prepared in this embodiment of the invention is beneficial for enhancing the endocytosis of IR780 and exhibits a strong enhanced tumor cell killing ability after light irradiation.

[0140] The above description is merely a preferred embodiment of the present invention and is not intended to limit the present invention in any way. Although the present invention has been disclosed above with reference to preferred embodiments, it is not intended to limit the present invention. Any person skilled in the art can make some modifications or alterations to the above-described technical content to create equivalent embodiments without departing from the scope of the present invention. Any simple modifications, equivalent changes, and alterations made to the above embodiments based on the technical essence of the present invention without departing from the scope of the present invention shall still fall within the scope of the present invention.

Claims

1. A method for preparing a ruthenium hydrogel drug delivery system, characterized in that, Includes the following steps: The first step, the preparation method of polydopamine nanocapsules, includes the following steps: Ammonia and dimethyldiethoxysilane in a volume ratio of 1:1 were dissolved in ultrapure water, ultrasonically dispersed for 10-20 minutes, and allowed to stand for 2-8 hours to obtain an emulsion mixture. Dopamine hydrochloride was added to Tris buffer solution with pH 8.5 and a concentration of 1–20 mmol / mL. The molar ratio of dopamine hydrochloride to tris(hydroxymethyl)aminomethane was 1:

15. The mixture was then sonicated to obtain a homogeneous dispersion. The mixture was then added to the emulsion mixture at a volume ratio of 1:

1. The mixture was sealed and stirred at 20–30°C for 1–24 h. Add an equal volume of anhydrous ethanol, sonicate for 1-10 minutes, let stand at room temperature for 1-24 hours, centrifuge, remove the supernatant, resuspend the sample in anhydrous ethanol and centrifuge again, repeat this operation to resuspend and centrifuge at least three times, resuspend the sample in ultrapure water and centrifuge again, repeat this operation to resuspend and centrifuge at least three times, wash with ultrapure water at least twice and dry to obtain the polydopamine nanocapsules. The second step, the preparation method of polydopamine composite IR780 nanocapsules, includes the following steps: The polydopamine nanocapsule solution and the DMSO solution of IR780 were mixed, with a mass ratio of polydopamine nanocapsules to IR780 of 1 to 3:

1. The mixture was stirred vigorously at room temperature for 1 to 24 hours, sonicated, and the supernatant was discarded. The mixture was centrifuged, and after removing the supernatant, the sample was resuspended in anhydrous ethanol and centrifuged again. This operation was repeated at least twice for resuspension and centrifugation. After removing the anhydrous ethanol, the sample was resuspended in ultrapure water and centrifuged again. This operation was repeated at least once for resuspension and centrifugation. The mixture was then dried to obtain PDA-IR780 nanocapsules. The third step, the preparation method of the ruthenium hydrogel drug delivery system Ru(fmb)3-HAADH@PDA-IR780, includes the following steps: Ruthenium hydrogel Ru(fmb)3-HAADH was dissolved in distilled water to obtain a Ru(fmb)3-HAADH hydrogel solution with a concentration of 5-50 mg / ml. PDA-IR780 nanocapsules were mixed with a ruthenium hydrogel solution Ru(fmb)3-HAADH at a concentration of 5–30 mg / ml and stirred rapidly. The mass ratio of PDA-IR780 nanocapsules to ruthenium hydrogel Ru(fmb)3-HAADH was 1:2–20. The mixture was washed with distilled water and lyophilized to obtain the ruthenium hydrogel drug delivery system Ru(fmb)3-HAADH@PDA-IR780. The preparation method of the ruthenium metal hydrogel in the third step includes the following steps: mixing hydrazide-modified hyaluronic acid solution with polypyridine ruthenium metal complex Ru(fmb)3Cl2 solution and stirring rapidly, wherein the mass ratio of hydrazide-modified hyaluronic acid to polypyridine ruthenium metal complex Ru(fmb)3Cl2 is 1-30:1, the stirring time is 1-3 min, dialysis purification is performed, and freeze drying is performed to obtain the ruthenium metal hydrogel Ru(fmb)3-HAADH; The preparation method of the hydrazide-modified hyaluronic acid solution includes the following steps: dissolving hydrazide-modified hyaluronic acid in distilled water to obtain a hydrazide-modified hyaluronic acid solution with a concentration of 10-50 mg / mL; The preparation method of the polypyridine ruthenium metal complex Ru(fmb)3Cl2 solution includes the following steps: dissolving the polypyridine ruthenium metal complex Ru(fmb)3Cl2 in distilled water to obtain a polypyridine ruthenium metal complex Ru(fmb)3Cl2 solution with a concentration of 1-5 mg / mL; The preparation method of the polypyridine ruthenium metal complex Ru(fmb)3Cl2 includes the following steps: under nitrogen protection, 4'-methyl-2,2'-bipyridine-4-carboxaldehyde is added to a Schlenk tube, dissolved in ethanol and water at a volume ratio of 2 to 8:1, and then RuCl3·3H2O is added, with a molar ratio of 4'-methyl-2,2'-bipyridine-4-carboxaldehyde to RuCl3·3H2O of 1 to 6:

1. The mixture is heated under reflux for 2 to 24 hours, cooled to room temperature, filtered, and the solution is evaporated to dryness to obtain a crude product. The crude product is dissolved in water, washed at least 3 times with excess dichloromethane, and purified by neutral alumina column chromatography to obtain the polypyridine ruthenium metal complex Ru(fmb)3Cl2. The method for preparing the hydrazide-modified hyaluronic acid includes the following steps: Low molecular weight sodium hyaluronate was dissolved in ultrapure water and stirred until completely dissolved. Adipic acid dihydrazide was added, with a mass ratio of sodium hyaluronate to adipic acid dihydrazide of 0.05–0.5:

1. The pH was adjusted to 6.5–7 with HCl or NaOH. Then, 1-hydroxybenzotriazole was slowly added, and the reaction was carried out for 15–60 min. Next, 1-ethyl-(3-dimethylaminopropyl)carbodiimide was added to the solution, with a mass ratio of 1-hydroxybenzotriazole to adipic acid dihydrazide of 0.01–1:1 and a mass ratio of 1-ethyl-(3-dimethylaminopropyl)carbodiimide to adipic acid dihydrazide of 0.01–1:

1. The pH was adjusted to 6.5–7 with HCl or NaOH every half hour for 1–5 h. The mixture was then stirred for 12–72 h. The mixture was purified by dialysis at least 3 times and then freeze-dried to obtain the hydrazide-modified hyaluronic acid.

2. The preparation method of the ruthenium hydrogel drug delivery system according to claim 1, characterized in that, In the second step, the polydopamine nanocapsules prepared in the first step are resuspended in water to a concentration of 0.5–3 mg / mL to obtain a polydopamine nanocapsule solution.

3. The method for preparing the ruthenium hydrogel drug delivery system according to claim 1, characterized in that, In the second step, IR780 is dissolved in DMSO to a concentration of 0.5–3 mg / mL to obtain a DMSO solution of IR780.

4. The preparation method of the ruthenium hydrogel drug delivery system according to claim 1, characterized in that, In the second step, the ultrasound conditions are: 300W ultrasound for 5 minutes; In the second step, the centrifugation conditions are: centrifugation at 13000 rpm for 15 min or 10 min.

5. The use of a ruthenium hydrogel drug delivery system prepared by the method according to any one of claims 1 to 4 in the preparation of antitumor drugs.

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