An ultrathin radioactive patch for skin cancer treatment and a preparation method thereof

Abstract

The application belongs to the technical field of biological medicine, and particularly relates to an ultrathin radioactive patch for skin cancer treatment and a preparation method thereof. The preparation method comprises the following steps: adding a photoinitiator solution into a methyl methacrylate gelatin solution, and performing water bath heating dissolution under light shielding conditions; after the dissolution is completed, mixing the radioactive particles used for external irradiation treatment, stirring to a semi-solid state, smearing to a patch bottom film by using a smearing part, covering the patch anti-adhesion paper on the surface, irradiating and curing by using a light source, and obtaining the ultrathin radioactive patch. The patch prepared by the application can be customized according to the size and shape of a lesion site, a corresponding bottom film is cut out and attached to the lesion site, and smearing is directly performed. Compared with a common radioactive hydrogel, the preparation method is simpler, the preparation time is shorter, and the efficiency is higher.

Description

Technical Field

[0001] This invention belongs to the field of biomedical technology, specifically relating to an ultrathin radioactive dressing for the treatment of skin cancer and its preparation method. Background Technology

[0002] The skin is the largest organ in the human body, and skin cancer is one of the most common malignant tumors. The incidence of skin tumors is increasing year by year. Clinically, they are mainly divided into two categories: melanocytic and non-melanocytic tumors (NMSCs). Melanoma has a lower incidence but a poorer prognosis. 80% of skin cancers belong to the non-melanoma category, such as basal cell carcinoma (BCC) and squamous cell carcinoma (SCC). These tumors rarely metastasize and are relatively easier to treat compared to melanoma.

[0003] Several well-defined treatment options are currently available for non-melanoma skin cancer (NMSCs), including surgical excision, cryotherapy, topical medications, and radiation therapy. Among these, treatments including local excision, plastic surgery, and Mozart's procedure have reported the highest control rates for NMSCs, reaching 94%–97%. For older patients, those with underlying medical conditions, or those with lesions in unusual locations such as the eyes, ears, or chest, who may find surgery too risky, fractionated brachytherapy using low-energy X-rays, electron beams, or sealed iridium-192 is typically employed, showing efficacy in 90%–95% of cases. Fractionated therapy requires daily treatment for several weeks; while short and convenient, low-dose fractionated treatment carries risks such as cell fibrosis and telangiectasia. Therefore, developing effective treatments for large-area lesions or lesions in unusual locations is a pressing issue.

[0004] In 2005, Sedda et al. proposed using an unsealed radioactive carrier matrix for tumor dressing therapy. The core advantage of this technology lies in its ability to overcome the limitations of three-dimensional tumor morphology through close-contact radiation, achieving precise matching between the radiation source and the lesion. Furthermore, the treatment process is simple, requires no hospitalization, is non-invasive, painless, and has a low recurrence rate. Currently, medical radioactive dressings used both domestically and internationally mainly include… 89 Sr- 90 Y-applied device and 32 P-patch is mainly used for hypertrophic scars and skin hemangiomas. According to literature reports, strontium aluminate glass microspheres are used as a carrier, and the mixture is delivered via ion exchange. 90 Y is replaced into the lattice of the microspheres, and then the drug-loaded microspheres are dispersed in silica gel and injected into a mold to form... 89 Sr- 90 The Y-type patch, due to its manufacturing process, contains a high level of radioactive impurities (such as...). 89 Sr、 90Sr), and the sealing process results in a thicker patch, which cannot fit the lesion site well and has a large amount of radiation self-absorption. Patent application CN116196541A discloses a phosphorus isotope patch, which places a phosphorus isotope layer between a first base layer and a second base layer. The preparation of phosphorus isotopes includes steps such as drawing properties, tracing and cutting, calculating area, multiple dripping of radionuclides and drying, which are cumbersome, waste radionuclides, and release aerosols into the environment. Patent application CN116983464A discloses a loaded 32 The method for preparing a hydrogel patch for p has been found that if the prepared hydrogel is too thick, it will hinder the transmission of beta rays, thus affecting the therapeutic effect; patent application CN119792586A discloses a loading method. 32 A method for preparing an ultrathin sheet-like chitosan hydrogel applicator, using chitosan hydrogel as a carrier and 32 The mixture of p-isotope solutions, poured into a mold, and sealed between two layers of transparent tape after photocuring, cannot achieve a complete fit to the lesion, resulting in radiation exposure to surrounding normal tissue and a higher risk. Both of these types of applicators are easy to apply to relatively flat lesions such as those on the arms, back, chest, and legs, but difficult to apply to areas such as the nose, earlobes, and between the fingers, making treatment of lesions in special locations challenging. Furthermore, neither is applicable to the treatment of skin cancer. Rhenium [Re-188], as a therapeutic isotope, has a significantly higher β-radiation energy (1.9-2.1 MeV) than iridium-192, while its 150 keV gamma-ray energy is perfectly suited to gamma imaging systems. Moreover, the epidermal dose gradient formed by rhenium-188 is gentler than that of iridium-192, and the dose value decays exponentially to near zero at a tissue depth of several millimeters, making it suitable for the treatment of superficial non-melanocytic skin cancer. The AlGa Institute and Medical Department in Italy coated a resin containing rhenium-188 onto an adhesive foil and applied it to non-melanoma skin cancer lesions to study its therapeutic effect on skin cancer, showing that it has a good therapeutic effect on this disease. However, the preparation of the dressing using resin particles has problems such as uneven coating, low rhenium adsorption efficiency, long preparation time, and uncontrollable flowability.

[0005] Therefore, exploring effective ultrathin radioactive dressings for the treatment of skin cancer is a pressing technical problem that needs to be solved. Summary of the Invention

[0006] The purpose of this invention is to solve the above-mentioned problems and provide an ultra-thin radioactive dressing for the treatment of skin cancer that has good adhesion to the lesion and uniform distribution of radionuclides, thus filling a technological gap.

[0007] A first aspect of the present invention provides a method for preparing an ultrathin radioactive dressing for the treatment of skin cancer, the method comprising:

[0008] A photoinitiator solution is added to a methacrylated gelatin solution and dissolved by heating in a water bath under light-protected conditions. After dissolution, it is mixed with radioactive particles for external irradiation therapy and stirred until semi-solid. The mixture is then applied to the base film of the dressing using an applicator, and a release liner is placed on the surface. The dressing is then cured by irradiation with a light source to obtain an ultra-thin radioactive dressing.

[0009] Semi-solid refers to a substance that has a certain shape and stability, but is not as hard and fixed as a solid, and has a certain degree of fluidity and plasticity.

[0010] The method for preparing an ultrathin radioactive patch for skin cancer treatment in this invention, wherein the radioactive particles used for external irradiation therapy are rhenium sulfide [Re-188] particles, phosphorus-32 particles, yttrium-90 particles, holmium-166 particles or lutetium-177 particles with a particle size ≤50μm.

[0011] As a preferred embodiment, in the preparation method of the above-mentioned ultrathin radioactive dressing for skin cancer treatment, the photoinitiator is selected from one or more of the following: lithium phenyl-2,4,6-trimethylbenzoyl phosphite, 2-methyl-1-(4-methylthiophenyl)-2-morpholino-1-propanone, α-amino ketone photoinitiators, 2-benzyl-2-dimethylamino-1-(4-morpholinophenyl)butanone, and bis(2,4,6-trimethylbenzoyl)phenylphosphine oxide.

[0012] As a preferred embodiment, in the above-mentioned method for preparing the ultrathin radioactive dressing for skin cancer treatment, the concentration of the photoinitiator solution is 0.5~5 mg / mL.

[0013] As a preferred embodiment, in the above-mentioned method for preparing ultrathin radioactive dressings for skin cancer treatment, the concentration of the methacrylated gelatin solution is 50-300 mg / mL.

[0014] As a preferred embodiment, in the above-mentioned method for preparing an ultrathin radioactive dressing for the treatment of skin cancer, the dressing base film is a polyethylene film, an ultrathin silicone rubber film, aluminum foil, a polyethylene terephthalate film, or a polyurethane film.

[0015] As a preferred embodiment, in the preparation method of the above-mentioned ultrathin radioactive dressing for the treatment of skin cancer, the water bath heating temperature is 40-80℃.

[0016] As a preferred embodiment, in the above-mentioned method for preparing the ultrathin radioactive dressing for skin cancer treatment, the irradiation light source for curing is 200-485 nm, and the curing time is 10-60 seconds. Those skilled in the art can select a photoinitiator based on the thickness of the substrate film, and determine the wavelength of light and the irradiation time based on the initiator.

[0017] According to one specific embodiment of the present invention, the method for preparing rhenium sulfide [Re-188] particles includes:

[0018] A first mixture was prepared by mixing sodium thiosulfate aqueous solution and sodium perrhenate [Re-188] aqueous solution; a second mixture was prepared by mixing polyvinylpyrrolidone aqueous solution and NaOH solution; an excipient (which provides a crystal nucleus for precipitate formation) was added to the first mixture and mixed until the excipient was completely dissolved; a strong acid solution was added to adjust the pH of the system to 1-2; the mixture was stirred and heated, cooled to room temperature, and then the second mixture was added to it. After mixing, the pH was adjusted to 4-9, and finally ultrasonically dispersed to obtain the rhenium sulfide [Re-188] particles.

[0019] As a preferred embodiment, the above-described method for preparing the ultrathin radioactive dressing for skin cancer treatment satisfies at least one of the following characteristics:

[0020] The concentration of the polyvinylpyrrolidone solution is 0.1~1 mol / L;

[0021] The molecular weight of polyvinylpyrrolidone is 58,000 to 1,300,000 Daltons;

[0022] The concentration of the NaOH solution is 0.005-0.02 mol / L;

[0023] The molar ratio of sodium thiosulfate to sodium perrhenate is (1~80):1;

[0024] The excipient is one or more of sodium chloride, sodium carbonate, and sodium bicarbonate;

[0025] The strong acid solution is a hydrochloric acid solution with a concentration of 1-8 mol / L;

[0026] The stirring and heating temperature is 40~140℃, and the time is 15-90min;

[0027] The ultrasonic dispersion time is 15-30 minutes;

[0028] The particle size of rhenium sulfide [Re-188] particles ranges from 200 nm to 10 μm.

[0029] A second aspect of the present invention provides an ultrathin radioactive dressing for the treatment of skin cancer, the ultrathin radioactive dressing being prepared by the above-described preparation method, the thickness of the ultrathin radioactive dressing being 0.1-1 mm.

[0030] Compared with the prior art, the present invention has at least the following beneficial effects:

[0031] Most existing radioactive dressings are made of hydrogel, and the physical properties of hydrogel result in thicker dressings. The methacrylated gelatin solution of this invention has a certain viscosity, and when applied with a spatula, a very small amount of gelatin solution can be used to coat the base film, thereby preparing an ultra-thin, uniformly distributed radioactive dressing. This reduces the absorption of radiation by the material itself, thus ensuring the therapeutic effect of the dressing on the lesion.

[0032] The dressing prepared by this invention can be customized according to the size and shape of the lesion. A suitable base film is cut and attached to the lesion, and then applied directly. Compared with ordinary radioactive hydrogels, the preparation method is simpler, the preparation time is shorter, and the efficiency is higher.

[0033] Precipitate the radioactive element rhenium [Re-188] and mix it with gelatin to ensure that the radioactive element is at the bottom of the patch, bringing it closer to the lesion and further enhancing the therapeutic effect of the radionuclide.

[0034] The above description is merely an overview of the technical solution of the present invention. In order to better understand the technical means of the present invention and to implement it in accordance with the contents of the specification, and in order to make the above and other objects, features and advantages of the present invention more apparent and understandable, specific embodiments of the present invention are described below. Attached Figure Description

[0035] Figure 1 A photograph of the rhenium patch sample prepared in Example 1;

[0036] Figure 2 This is a schematic diagram showing the thickness measurement of the rhenium plaster sample prepared in Example 1.

[0037] Figure 3 This is a schematic diagram of the cross-sectional thickness measurement of the rhenium patch sample prepared in Example 2;

[0038] Figure 4 The results show the characterization of rhenium sulfide particles in the rhenium patch sample prepared in Example 2. Detailed Implementation

[0039] To make the objectives, technical solutions, and advantages of this invention clearer, the technical solutions in this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some, not all, of the embodiments of this invention. All other embodiments obtained by those skilled in the art based on the embodiments of this invention without creative effort are within the scope of protection of this application.

[0040] It should be noted that the sodium perrhenate [Re-188] solution in the following embodiments is generated by a tungsten-rhenium generator (“a type of…”). 188 W- 188Preparation method and apparatus for Re generator (Acceptance No.: CN202310704356.2) is prepared by rinsing. In this embodiment of the invention, the sodium perrhenate [Re-188] solution contains: sodium perrhenate at a specific molar concentration + sodium perrhenate [Re-188] at a specific radioactive concentration.

[0041] In this embodiment of the invention, polyvinylpyrrolidone (PVP) is sourced from Shanghai Maclean Biochemical Technology Co., Ltd., MW58000-1300000; GelMA is methacrylated gelatin.

[0042] In each embodiment, the particle size of the rhenium sulfide precipitate is in the range of 0.6-6.48 μm.

[0043] Example 1

[0044] This embodiment provides a method for preparing an ultrathin rhenium patch, including:

[0045] (1) Weigh 58.5 g of sodium thiosulfate (Na2S2O3) and dissolve it in 500 mL of pure water. Boil slowly for 10 minutes, cool and set aside. Store the prepared solution (concentration of 0.74 mol / L) in a brown volumetric flask to prevent light exposure.

[0046] (2) Measure 43 mL of 36% hydrochloric acid into a beaker, dilute and dissolve it with pure water, and then use a glass rod to guide the flow into a volumetric flask. The volume can be adjusted to 100 mL to obtain a 5 mol / L hydrochloric acid solution.

[0047] (3) Weigh out polyvinylpyrrolidone (PVP) with a molecular weight of k30, add it to 50 mL of water while stirring, and prepare a 10wt% PVP aqueous solution.

[0048] (4) Weigh 40 mg of sodium hydroxide into a beaker, add 50 mL of pure water to dissolve it completely, transfer it to a volumetric flask and make up to 100 mL to obtain a 0.01 mol / L sodium hydroxide solution.

[0049] (5) Prepare the initiator solution by taking the required mass of lithium phenyl-2,4,6-trimethylbenzoyl phosphite (LAP), adding it to PBS solution, shaking it in a 50 °C water bath in the dark, and heating it to dissolve for 15 minutes to obtain a 5 mg / mL LAP solution.

[0050] (6) Prepare GelMA solution. Take the required mass of GelMA and put it into a centrifuge tube. Add the initiator standard solution obtained in step (5) into the centrifuge tube and shake to fully wet the GelMA. Heat and dissolve in a 60°C water bath (away from light) for 30 minutes to obtain a 200 mg / mL GelMA solution. Keep the GelMA solution in a 37°C water bath away from light for later use.

[0051] (7) Take 1 mL each of the sodium thiosulfate solution with a concentration of 0.74 mol / L and the sodium perrhenate solution with a concentration of 0.01875 mol / L prepared in step (1) into a beaker. The molar ratio of sodium thiosulfate to sodium perrhenate is 40:1. Add 50 mg of sodium chloride and mix well. Add 0.4 mL of 5 mol / L hydrochloric acid solution, stir well, and then place in a water bath at 60 °C for 30 min.

[0052] (8) Take 1 mL of the PVP aqueous solution prepared in step (3) and 1 mL of the NaOH aqueous solution prepared in step (4), mix them well and set aside.

[0053] (9) After the solution in step (7) is cooled to room temperature, it is mixed with the solution in step (8), and the pH is adjusted to 6 after mixing.

[0054] (10) Place the mixed solution from step (9) in an ultrasonic container, disperse for 15 min, and then centrifuge to obtain rhenium sulfide precipitate.

[0055] (11) Inject the GelMA solution into the rhenium sulfide precipitate and stir until semi-solid. Take a portion of the semi-solid material and spread it onto the polyethylene terephthalate film (1cm×1cm) with a scraper. Apply release paper as the surface layer and irradiate with a 405nm light source for 30 seconds to gel, thus obtaining an ultra-thin sheet-like dressing loaded with rhenium.

[0056] Figure 1 A photograph of the rhenium patch sample prepared in Example 1. Figure 2 This is a schematic diagram showing the thickness measurement of the rhenium plaster sample prepared in Example 1. Figure 2 In the image: 2a is a vertical front view of the patch, 2b is a vertical front view of the patch after it has been cut, 2c is a vertical side view of the patch, and 2d is a vertical side view of the patch after it has been cut. The thickness of the sample at its thickest point is approximately 0.2 mm.

[0057] Example 2

[0058] In this embodiment, four groups of samples were prepared. The only difference between each group of samples was the particle size of the rhenium sulfide precipitate. The preparation steps are as follows:

[0059] (1) Prepare sodium thiosulfate solutions of 0.1 mol / L, 0.2 mol / L, 0.6 mol / L and 0.8 mol / L respectively.

[0060] (2) The hydrochloric acid solution is the same as in Example 1.

[0061] (3) The PVP solution is the same as in Example 1.

[0062] (4) Sodium hydroxide solution is the same as in Example 1.

[0063] (5) The initiator solution is the same as in Example 1.

[0064] (6) The GelMA solution is the same as in Example 1.

[0065] (7) Take 1 mL of sodium perrhenate solution with a concentration of 0.01 mol / L and add it to 4 different beakers. Then, take 1 mL of sodium thiosulfate solution with different concentrations according to the molar ratio of sodium thiosulfate to sodium perrhenate of 10:1, 20:1, 60:1 and 80:1 and add it to 4 sodium perrhenate beakers. Then, add 50 mg of sodium chloride to each beaker and mix well. Add 0.4 mL of 5 mol / L hydrochloric acid solution, stir well and then put it in a water bath at 60 ℃ for 30 min.

[0066] (8) The operation is the same as in Example 1.

[0067] (9) The operation is the same as in Example 1.

[0068] (10) The operation is the same as in Example 1.

[0069] (11) The operation is the same as in Example 1.

[0070] Rhenium sulfide precipitate and coating prepared by a molar ratio of sodium thiosulfate and sodium perrhenate of 80:1 were used for characterization. The cured coating was cut along the middle to observe the thickness of the cross-sectional section. Simultaneously, electron microscopy was used to analyze the particle size and dispersion of the rhenium sulfide. Figure 3 This is a schematic diagram showing the cross-sectional thickness measurement of the rhenium plaster sample prepared in Example 2. Figure 4 The following are the characterization results of the rhenium sulfide particles in the rhenium patch sample prepared in Example 2. It can be seen that the thickness of the patch at its thickest point is about 0.2~0.5 mm, the rhenium sulfide particles are about 1-10 μm, the dispersion is good, and the particle size is uniform.

[0071] Example 3

[0072] In this embodiment, three groups of samples were prepared. The only difference between each group of samples was the radioactivity of the nuclide. The preparation steps are as follows:

[0073] (1) Prepare a 0.8 mol / L sodium thiosulfate solution.

[0074] (2) The hydrochloric acid solution is the same as in Example 1.

[0075] (3) The PVP solution is the same as in Example 1.

[0076] (4) Sodium hydroxide solution is the same as in Example 1.

[0077] (5) The initiator solution is the same as in Example 1.

[0078] (6) The GelMA solution is the same as in Example 1.

[0079] (7) Take 2 mL each of sodium thiosulfate and sodium perrhenate [Re-188] solution with a molar ratio of 80:1 and add them to beakers. Then add 100 mg of sodium chloride and mix well. Add 0.8 mL of 5 mol / L hydrochloric acid solution, stir well, and then place in a water bath at 60 ℃ for 30 min. Prepare 3 groups of samples in the same way. The radioactivity of Re-188 nuclide in the 3 groups of samples are 0.5 mCi / mL, 1 mCi / mL, and 2 mCi / mL, respectively.

[0080] (8) Take 2 mL of PVP and NaOH solution into a beaker, mix well and set aside.

[0081] (9) The operation is the same as in Example 1.

[0082] (10) The operation is the same as in Example 1.

[0083] (11) The GelMA solution was injected into the rhenium sulfide precipitate and stirred until semi-solid. The semi-solid was then spread onto a polyethylene terephthalate film (20cm×20cm) using a spatula. An adhesive release paper was applied as the surface layer, and the film was irradiated with a 405nm light source for 30 seconds to gel, resulting in an ultra-thin rhenium-loaded sheet-like patch. The thickness of all three samples was approximately 0.4mm. The three samples in Example 3 were quantitatively analyzed using a high-purity germanium gamma spectroscopy instrument. The results showed that the activities of each sample near the bottom film after patch preparation were 0.87mCi, 1.78mCi, and 3.56mCi, respectively, demonstrating a high radionuclide utilization rate during the patch preparation process.

[0084] Example 4

[0085] In this embodiment, three groups of samples were prepared, with the only difference between each group being their thickness. The preparation steps are as follows:

[0086] (1) Prepare a 0.7 mol / L sodium thiosulfate solution.

[0087] (2) The hydrochloric acid solution is the same as in Example 1.

[0088] (3) The PVP solution is the same as in Example 1.

[0089] (4) Sodium hydroxide solution is the same as in Example 1.

[0090] (5) The difference from Example 1 is that the concentration of the initiator solution is 2.5 mg / mL.

[0091] (6) The difference from Example 1 is that a GelMA solution of 300 mg / mL is obtained.

[0092] (7) Take 0.5, 1 and 2 mL of sodium thiosulfate and sodium perrhenate [Re-188] solution (1 mCi / mL) with a molar ratio of 70:1 into a beaker, add 100 mg of sodium chloride and mix well, add 0.8 mL of 5 mol / L hydrochloric acid solution, stir well, and then place in a water bath at 60 ℃ for 30 min.

[0093] (8) Take 2 mL each of PVP and NaOH solution into a beaker, mix well and set aside.

[0094] (9) The operation is the same as in Example 1.

[0095] (10) The operation is the same as in Example 1.

[0096] (11) The GelMA solution was injected into the rhenium sulfide precipitate and stirred until semi-solid. A portion of the semi-solid was taken and spread onto a polyethylene terephthalate film (20cm×20cm) with a spatula. An adhesive release paper was applied as a surface cover, and the film was irradiated with a 405nm light source for 30 seconds to gel, resulting in an ultra-thin sheet-like patch loaded with rhenium. The patch sample was removed and quantitatively analyzed using a high-purity germanium gamma spectroscopy instrument. The thicknesses were 0.145mm, 0.17mm, and 0.44mm, and the activities (bottom facing down during measurement) of the patches from thin to thick were 0.21mCi, 0.76mCi, and 1.47mCi, respectively.

[0097] Comparative Example 1

[0098] The difference from Example 1 is that step (11) uses the existing gel method to prepare rhenium-188 patch with a thickness of about 0.5~0.8 mm, while the patch prepared by the present invention has a thickness of less than 0.5 mm.

[0099] The above are merely preferred embodiments of the present invention and are not intended to limit the present invention. Various modifications and variations can be made to the present invention by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. A method for preparing an ultrathin radioactive dressing for the treatment of skin cancer, characterized in that, The preparation method includes: A photoinitiator solution was added to a methacrylated gelatin solution and dissolved by water bath heating under light-protected conditions. After dissolution, it was mixed with radioactive particles for external irradiation therapy and stirred until semi-solid. The mixture was then applied to the base film of the dressing using an applicator, and the release paper was placed on the surface. The dressing was then cured by light source irradiation to obtain an ultra-thin radioactive dressing. The radioactive particles used for external irradiation therapy are rhenium sulfide [Re-188] particles with a particle size ≤50μm.

2. The method for preparing the ultrathin radioactive dressing for skin cancer treatment according to claim 1, characterized in that, The photoinitiator is selected from one or more of the following: phenyl-2,4,6-trimethylbenzoyl lithium phosphite, 2-methyl-1-(4-methylthiophenyl)-2-morpholino-1-propanone, α-amino ketone photoinitiators, and bis(2,4,6-trimethylbenzoyl)phenylphosphine oxide. The concentration of the photoinitiator solution is 0.5~5 mg / mL; The concentration of the methacrylated gelatin solution is 50-300 mg / mL.

3. The method for preparing the ultrathin radioactive dressing for skin cancer treatment according to claim 1, characterized in that, The substrate film is a polyethylene film, an ultra-thin silicone rubber film, aluminum foil, polyethylene terephthalate film, or a polyurethane film.

4. The method for preparing the ultrathin radioactive dressing for skin cancer treatment according to claim 1, characterized in that, The water bath heating temperature is 40-80℃.

5. The method for preparing the ultrathin radioactive dressing for skin cancer treatment according to claim 1, characterized in that, The light source for curing is 200-485nm, and the curing time is 10-60 seconds.

6. The method for preparing the ultrathin radioactive dressing for skin cancer treatment according to claim 1, characterized in that, The preparation methods of rhenium sulfide [Re-188] particles include: A first mixture was obtained by mixing sodium thiosulfate aqueous solution and sodium perrhenate [Re-188] aqueous solution; a second mixture was obtained by mixing polyvinylpyrrolidone aqueous solution and NaOH solution; an excipient was added to the first mixture and mixed until the excipient was completely dissolved; a strong acid solution was added to adjust the pH of the system to 1-2; the mixture was stirred and heated, cooled to room temperature, and then the second mixture was added to it. After mixing, the pH was adjusted to 4-9, and finally ultrasonically dispersed to obtain the rhenium sulfide [Re-188] particles.

7. The method for preparing the ultrathin radioactive dressing for skin cancer treatment according to claim 6, characterized in that, Satisfy at least one of the following characteristics: The concentration of the polyvinylpyrrolidone solution is 0.1~1 mol / L; The molecular weight of polyvinylpyrrolidone is 58,000 to 1,300,000 Daltons; The concentration of the NaOH solution is 0.005-0.02 mol / L; The molar ratio of sodium thiosulfate to sodium perrhenate is (1~80):1; The excipient is one or more of sodium chloride, sodium carbonate, and sodium bicarbonate; The strong acid solution is a hydrochloric acid solution with a concentration of 1-8 mol / L; The stirring and heating temperature is 40~140℃, and the time is 15-90min; The ultrasonic dispersion time is 15-30 minutes; The particle size of rhenium sulfide [Re-188] particles ranges from 200 nm to 10 μm.

8. An ultrathin radioactive dressing for the treatment of skin cancer, characterized in that, The ultrathin radioactive dressing is prepared by the preparation method according to any one of claims 1-7.

9. The ultrathin radioactive dressing for skin cancer treatment according to claim 8, characterized in that, The thickness of the ultrathin radioactive dressing is 0.1-1 mm.

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