Iodine nuclide silk mantle, preparation method and radioactive stent

Abstract

The invention provides an iodine nuclide silk mantle, a preparation method and a radioactive stent, and relates to the technical field of high polymer materials. The preparation method of the iodine nuclide silk mantle comprises the following steps: 1) weaving pretreated mulberry silk to obtain a filiform mantle; and 2) labeling the filiform mantle with iodine 125 to obtain the iodine nuclide silk mantle. Detachably sleeving the surface of a stent tube with the prepared iodine nuclide silk sleeve film to obtain the radioactive stent. The radioactive stent can destroy active mitotic tumor cells, can solve biliary obstruction caused by malignant tumors, has an obvious tumor treatment effect, and is high in operability and convenient to use.

Description

Technical Field

[0001] The invention relates to the technical field of polymer materials, and in particular to an iodine-based nuclide silk mantle, a preparation method and a radioactive stent. Background Art

[0002] There are many pipeline structures in the human organ system, such as the digestive tract (e.g. esophagus, stomach, duodenum, small intestine, colon, bile duct, pancreatic duct), respiratory tract (trachea, bronchi), urinary tract (ureter). These pipelines are necessary channels to maintain the normal function of the human body. Once blocked, it will cause very serious or even fatal consequences. However, these pipeline structures are also high-incidence sites of human malignant tumors. As far as the digestive tract is concerned, esophageal cancer, gastric cancer, colon cancer, bile duct and duodenal cancer are all malignant tumors. A common clinical feature of malignant tumors in these pipeline systems is that when the course of the disease reaches a certain extent, it will inevitably lead to obstruction of the pipeline. Esophageal cancer can cause swallowing obstruction and inability to eat in patients, colon cancer can cause intestinal obstruction and vomiting, and bile duct and duodenal cancer can block bile drainage and cause jaundice and liver damage. Although surgical resection of the tumor can relieve the obstruction. However, for patients who cannot undergo surgical resection due to various reasons such as advanced age, advanced stage or organ dysfunction, inserting a stent tube at the obstruction site through intervention is almost the only way to relieve the obstruction for these patients. On this basis, different materials (including metals, polymer materials, etc.) have been used to target different types of tumors, and various forms and types of stent systems have been gradually developed, including esophageal stents, biliary stents, intestinal stents, ureteral stents, etc. These stents can relieve esophageal and intestinal obstructions, allowing patients to resume eating, restore bile duct patency, eliminate jaundice, and protect liver function. The use of stent tubes has enabled many patients to resume normal life, etc.

[0003] For malignant tumors in the gallbladder and pancreas, such as pancreatic cancer, bile duct cancer, and duodenal cancer, these patients often have tumors that gradually grow and compress the bile duct during the progression of the disease, resulting in bile excretion obstruction and bile retention, followed by severe liver damage and digestive dysfunction, which are the main reasons for the deterioration of malignant tumors in the gallbladder and pancreas. Many patients die of liver failure or obstructive jaundice before the tumor reaches the advanced stage. Clinically, the surgical resection rate of malignant tumors in the gallbladder and pancreas is very low (about 10% + / -). Most patients can only use palliative treatment, mainly using various means to relieve bile duct obstruction, and bile drainage has become an important means of clinical treatment. At present, bile duct stents made of various types of metals or polymer materials can be used to relieve obstruction and drain bile through percutaneous transhepatic PTCD catheterization technology or ERCP technology through duodenal papilla bile duct catheterization. These treatment measures have greatly improved the quality of life of patients and reduced liver damage, providing some patients with surgical treatment opportunities.

[0004] However, all stent technologies cannot provide any therapeutic effect on malignant tumors themselves. The single use of this technology cannot prolong the patient's survival time. Therefore, people began to think about whether radioactive stent tubes can relieve obstruction, unblock drainage, and treat malignant tumors at the same time. The use of radioactive stents to treat gallbladder and pancreatic malignancies and relieve bile duct obstruction at the same time is an ideal treatment for malignant tumor duct obstruction. Although many scholars have conducted various explorations on duct radioactive stents, few have been successfully applied in clinical practice.

[0005] The existing iodine-125 particle strips, which are made by embedding iodine-125 particles during surgery and inserting them together with stent tubes, have been reported and shown to be effective for malignant tumor bile duct obstruction. However, the operation is relatively complicated. First, the particle strips must be filled during surgery. The operation process is very delicate and complicated, and it is very difficult for medical staff to operate. It must even be assisted by professional salesmen to complete it. There are also many side effects of metal implantation in the body, such as the inability to degrade, and the inability to perform magnetic resonance imaging (MR) and PETCT after surgery. These obvious side effects may even affect new radionuclide therapies in the future. Furthermore, the cost of particle strips is very expensive and the cost of treatment is high. Some scholars have also proposed a biliary radioactive stent that is coated on the outside of the stent tube and then labeled with isotopes. However, due to the strict qualification restrictions on the production of radionuclide drugs, the possibility of producing radionuclide stents in existing stent tube manufacturers is very small. Summary of the invention

[0006] The purpose of the present invention is to provide an iodine-based radionuclide silk mantle, which can destroy tumor cells in active mitosis and is beneficial to tumor treatment.

[0007] Another object of the present invention is to provide a method for preparing an iodine-based radionuclide silk mantle, which can increase the labeling rate of iodine-125 on mulberry silk, so that the iodine-based radionuclide silk mantle has a higher radiation amount, thereby achieving the purpose of treating tumors.

[0008] Another object of the present invention is to provide a radioactive stent, which can not only solve the bile duct obstruction caused by malignant tumors, but also has obvious tumor treatment effect, strong operability and easy use.

[0009] The present invention is achieved through the following technical solutions:

[0010] In a first aspect, a method for preparing an iodine-based nuclide silk mantle is provided, comprising the following steps:

[0011] 1) Weaving the pretreated mulberry silk to obtain a filamentous mantle:

[0012] 2) Label the filamentous mantle with iodine-125 to obtain an iodine-based radionuclide silk mantle.

[0013] Silk is the earliest medical biomaterial used by humans, and its biocompatibility and biodegradability have been deeply studied. Silk thread is a material that is allowed to be used in surgical sutures and has been used in medical practice for hundreds of years. The safety of silk has long been confirmed. The inventor has confirmed through experiments that because the sericin and fibroin in silk contain rich (6%) tyrosine, they can react with iodine 125 to form a halogenation reaction with amino groups, thereby labeling iodine 125 at a high concentration. The labeling rate of silk in the present invention has reached 150μCi / mg, so that even a small amount of silk mantle can achieve a high radiation dose. This feature enables even a small amount of silk mantle to achieve the purpose of treating tumors. The experimental results of the present invention prove that the radiation dose of the iodine-based radionuclide silk mantle is fully capable of achieving the effect of tumor treatment.

[0014] The treatment mechanism is: using the gamma rays released by the high-radiation iodine-125 of the radionuclide silk mantle to destroy tumor cells in active mitosis. The effective radiation range of iodine-125 is 1.7 to 2.0 cm. According to cancer cell treatment experiments, the effective treatment range of the radionuclide iodine-125 silk mantle is 3-4 cm, while the volume of esophageal, intestinal, bile duct or pancreatic tumors is generally around 1-3 cm. This effective range of radiation is consistent with the size of most digestive tract tumors. The half-life of iodine-125 is 60 days, and the effective biological half-life in the body is 41.7 days. These characteristics are more favorable for the treatment of tumors including the intestine, esophagus, and bile duct.

[0015] Further, in step 1), the weaving angle of the mulberry silk in a relaxed state is 5°-95°, and the number of strand ends is 4-24. The silk mantle is woven in a tubular form, the density of the tubular braid is controlled by different weaving processes, the diameter of the inner tube is controlled by controlling the diameter of the core material, and the tubular braided tube is woven into a prototype of the silk mantle by manual / mechanical operation.

[0016] Furthermore, in step 1), the pretreatment of the mulberry silk includes degumming, soaking, doubling, twisting and shaping. The soaking is carried out with a special auxiliary agent for 3-10 minutes. The special auxiliary agent is sodium carbonate or sodium silicate, which can help dissolve impurities in the silk.

[0017] Furthermore, the filamentous mantle is one or more of a biliary stent mantle, an intestinal stent mantle, an esophageal stent mantle and a ureteral stent mantle, wherein the biliary stent has a long diameter of 3.0-3.5 cm and a wide diameter of 0.22 cm.

[0018] Furthermore, in step 2), the iodine-125 labeling step includes: placing the filamentous mantle into an EP tube, adding iodine-125 solution, PBS solution and chloramine-T solution in sequence, and shaking the reaction at room temperature for 30 minutes; collecting the reaction liquid, shaking and washing the filamentous mantle with ultrapure water, and collecting the washing liquid. The washing is repeated twice, and the washing is shaken at room temperature for 2 minutes.

[0019] Preparation of iodine 125 solution: Use a pipette to take 350 μL of Na 125 I solution source solution into the vial, measured activity is 10.38mCi, add 12mL ultrapure water (deionized water), prepare Na 125 I solution (specific activity: 0.865 mCi / mL).

[0020] Preparation of PBS solution: weigh Na 2 HPO 4 and NaH 2 PO 4 , prepare PBS solution with a concentration of 0.3 mol / L, dilute to 500 mL, and adjust the pH to 7.46 using a pH meter. Note: Ensure the concentration and pH value of the PBS solution (7.2-7.6).

[0021] Preparation of Chloramine-T solution: Weigh 10±0.005 mg of Chloramine-T, dissolve in a beaker, and ultrasonicate for 10 seconds to ensure full dissolution. Transfer to a 10 mL volumetric flask and make up to 10 mL, concentration: 1 mg / mL. Chloramine-T solution should be prepared and used immediately.

[0022] In a second aspect, an iodine-based radionuclide silk mantle is provided, which is produced by the above-mentioned preparation method of the iodine-based radionuclide silk mantle.

[0023] In a third aspect, a radioactive stent is provided, comprising the above-mentioned iodine-based radionuclide silk sheath and a stent tube, wherein the iodine-based radionuclide silk sheath is detachably sheathed on the surface of the stent tube.

[0024] The technical solution of the present invention has at least the following advantages and beneficial effects:

[0025] Compared with various existing radioactive stent tubes, the radioactive stent of the present invention has strong operability, is easy to use, has a definite effect, and has no metal objects left in the body for a long time. Compared with the expensive iodine-125 particle strips, the radioactive stent provided by the present invention is relatively cheap. Due to the high specific activity of the nuclides in the silk mantle, the soft and thin mantle can fit tightly with the stent tube, can be detachably mounted on the stent tube, and has many advantages such as being fully compatible with the original endoscopic stent catheter implantation equipment system and operating system. In particular, the iodine-based nuclides silk mantle and the stent tube are produced by qualified manufacturers respectively, and are perfectly combined when used. Under the existing drug management system, it is a relatively practical new product.

[0026] Among them, the iodine-based radionuclide silk mantle is designed to match the most commonly used stent tube in clinical practice. When in use, it only needs to be detachably sheathed on the stent tube, so clinical physicians do not need to change their usual work and operating procedures and habits. It is easy to operate and convenient to use, which is conducive to clinical promotion and application. In particular, the softness and strong plasticity of silk can be adjusted and modified according to the specifications of various stent tubes, and can be widely expanded to any other luminal organ cancer obstruction. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] Figure 1 Schematic diagram of the stent tube and the iodine-based radionuclide silk sheath provided by the present invention, wherein the left side is the existing clinically used biliary stent (including the outer sleeve and the stent tube), and the right side is the iodine-based radionuclide silk sheath, and the diameter of the sheath is consistent with the diameter of the stent tube;

[0028] Figure 2 A schematic diagram of the process of encapsulating the stent tube and the iodine-based radionuclide silk sheath provided by the present invention;

[0029] Figure 3 This is a schematic diagram of detecting cell viability using CCK-8 of the present invention;

[0030] Figure 4 This is a schematic diagram of the cell death rate detected by LDH cytotoxicity of the present invention;

[0031] Figure 5 This is a schematic diagram of fluorescent staining of Calcein AM / PI live and dead cell double staining of the present invention;

[0032] Figure 6 This is a microscopic schematic diagram of HE staining of the blank control group in the present invention;

[0033] Figure 7 It is a microscopic schematic diagram of HE staining of the gastric cancer stent group in the present invention. DETAILED DESCRIPTION

[0034] The present invention is further described below in conjunction with specific embodiments, but the embodiments do not limit the present invention in any form. Unless otherwise specified, the raw materials and reagents used in the embodiments of the present invention are conventionally purchased raw materials and reagents.

[0035] Example 1

[0036] A method for preparing an iodine-based nuclide silk mantle comprises the following steps:

[0037] 1) Making a filamentous mantle:

[0038] 1.1. Degumming the silk conventionally, soaking it in a special auxiliary agent for 5 minutes, taking it out, doubling, twisting and shaping it;

[0039] 1.2. The shaped mulberry silk is woven into a tube by manual or machine operation. The weaving angle of the mulberry silk is 60° in a relaxed state, and the number of strand ends is 10. The obtained filamentous sheath is:

[0040] 2) Marking the filamentous mantle:

[0041] 2.1. Place the filamentous mantle into an EP tube, add iodine 125 solution, PBS solution and chloramine-T solution in sequence, and use a vortex oscillator to shake and react at room temperature for 30 minutes; the specific activity of iodine 125 solution is 0.865mCi / mL, the concentration of PBS solution is 0.3mol / L, the pH is 7.46, and the concentration of chloramine-T solution is 1mg / mL;

[0042] 2.2. Collect the reaction solution with a pipette, add 1 mL of ultrapure water to the EP tube, place it on a vortex shaker at room temperature for 2 minutes to clean the filamentous mantle membrane, repeat the cleaning twice, and collect the cleaning solution.

[0043] Example 2

[0044] A method for preparing an iodine-based radionuclide silk mantle, taking a biliary stent mantle as an example, wherein the biliary stent mantle is adapted to a biliary branch, comprising the following steps:

[0045] 1) Making a filamentous mantle:

[0046] 1.3. Degumming the mulberry silk conventionally, soaking it in a special auxiliary agent for 3 minutes, taking it out, and then doubling, twisting and shaping it;

[0047] 1.4. The shaped mulberry silk is woven into a tube by manual or machine operation. The weaving angle of the mulberry silk is 95° in a relaxed state, and the number of strand ends is 24. The obtained biliary stent sleeve has a long diameter of 3.0 cm and a wide diameter of 0.22 cm:

[0048] 2) Marking the filamentous mantle:

[0049] 2.1. Place the bile duct cuff in the EP tube, add iodine 125 solution, PBS solution and chloramine-T solution in sequence, and use a vortex oscillator to shake and react at room temperature for 30 minutes; the specific activity of iodine 125 solution is 0.865mCi / mL, the concentration of PBS solution is 0.3mol / L, the pH is 7.46, and the concentration of chloramine-T solution is 1mg / mL;

[0050] 2.2. Collect the reaction solution with a pipette, add 1 mL of ultrapure water to the EP tube, place it on a vortex shaker at room temperature for 2 minutes to clean the filamentous mantle membrane, repeat the cleaning twice, and collect the cleaning solution.

[0051] Example 3

[0052] A method for preparing an iodine-based radionuclide silk mantle, taking a biliary stent mantle as an example, wherein the biliary stent mantle is adapted to a biliary branch, comprising the following steps:

[0053] 1) Making a filamentous mantle:

[0054] 1.5. Degumming the silk conventionally, soaking it in a special auxiliary agent for 10 minutes, taking it out, and then doubling, twisting and shaping it;

[0055] 1.6. The shaped mulberry silk is woven into a tube by manual or machine operation. The weaving angle of the mulberry silk is 5° in a relaxed state, and the number of strand ends is 4. The obtained biliary stent sleeve has a long diameter of 3.5 cm and a wide diameter of 0.22 cm:

[0056] 2) Marking the filamentous mantle:

[0057] 2.1. Place the bile duct cuff in the EP tube, add iodine 125 solution, PBS solution and chloramine-T solution in sequence, and use a vortex oscillator to shake and react at room temperature for 30 minutes; the specific activity of iodine 125 solution is 0.865mCi / mL, the concentration of PBS solution is 0.3mol / L, the pH is 7.46, and the concentration of chloramine-T solution is 1mg / mL;

[0058] 2.2. Collect the reaction solution with a pipette, add 1 mL of ultrapure water to the EP tube, place it on a vortex shaker at room temperature for 2 minutes to clean the filamentous mantle membrane, repeat the cleaning twice, and collect the cleaning solution.

[0059] Example 4

[0060] like Figure 1-2 As shown, this embodiment provides a radioactive stent, comprising the above-mentioned iodine-based radionuclide silk sheath and a stent tube, wherein the iodine-based radionuclide silk sheath is detachably sheathed on the surface of the stent tube, and further comprising sheathing an outer sleeve on the stent tube holder sheathed with the iodine-based radionuclide silk sheath.

[0061] The diameter of the iodine-based radionuclide silk mantle is consistent with the diameter of the support tube, and the diameter of the outer tube is consistent with the diameter of the operating hole of a conventional gastroscope, which can ensure that the gastroscope can smoothly enter the duodenal operating area during operation. Figure 2 The rightmost picture shows the actual situation of restoration of normal insertion through gastroscopy. There is an outer sleeve outside to ensure that the stent tube can be inserted normally. After insertion, the outer sleeve will be removed, so that the stent tube returns to its normal bending state.

[0062] Test results

[0063] The labeling results of Example 1-2 were tested, and the results were as follows:

[0064] Table 1 Marking rate of the mantle of Example 1-2

[0065]

[0066] According to the data in the table, embodiments 1-2 can obtain a mantle with a marking rate of about 43-46%, which has a relatively high marking rate.

[0067] Another silk was labeled with iodine 125 in the same manner as in Example 1. The results are as follows:

[0068] Table 2 Silk marking rate

[0069]

[0070] According to the data in the table, when a small amount of silk is labeled with iodine-125, the specific activity of the silk can be higher and the labeling rate of iodine-125 can be higher.

[0071] According to Table 1 and Table 2, when the mass of the mantle is 21.8 mg, the iodine-125 labeling rate is 43.12%, and combined with the results of the anti-cancer treatment experiment, a good anti-cancer treatment effect can be achieved at this labeling rate. When the mass of silk is 2.78 mg, the iodine-125 labeling rate is 83.8%. This shows that a small amount of silk can achieve a higher labeling rate, and a small amount of silk can be used to prepare a thinner iodine-based radionuclide silk mantle, which is more suitable for being mounted on different stents.

[0072] 1. Anti-cancer treatment experiment

[0073] 1. Experimental Grouping

[0074] Human gastric cancer cell line (MKN45): blank control group, gastric cancer stent group prepared with the nuclide silk sheath of Example 1.

[0075] 2. Therapeutic intervention methods:

[0076] The successfully labeled nuclide silk mantle was trimmed into 1.5 cm sections, and the cell culture wells were affixed to the paper bottom plate in a one-to-one correspondence according to the format of a 24-well cell culture dish. The pre-cultured mature cancer cells were aligned one by one on the gastric cancer scaffold made of nuclide silk mantle. Under standard cell culture conditions, each group was intervened for 3 and 4 days respectively, and the blank control group was cultured under the same conditions, and the observation time was the same as that of the gastric cancer scaffold group.

[0077] 2. Experimental testing

[0078] 1. CCK-8 detection of cell viability

[0079] Experimental methods:

[0080] (1) MKN45 cells in the logarithmic growth phase were digested with trypsin and then the cells were counted;

[0081] (2) The cells were inoculated in a 24-well culture plate, with three replicate wells in each group. When the cells grew well, they were grouped and treated according to the above experimental scheme;

[0082] (3) According to the instructions of the CCK-8 kit, 500uL of the prepared CCK-8 solution (CCK-8 reagent accounts for 10% of the total volume) was added to each well, and 3 blank replicate wells were set up. Incubate at 37°C in the dark for 1 h;

[0083] (4) After the incubation, the 24-well culture plate was taken out and shaken to mix well. The optical density (OD value) of each well at 450 nm was measured using a microplate reader and the cell survival rate was calculated.

[0084] Experimental results: According to Figure 3 It can be seen that the cell survival rate in the gastric cancer stent group is lower than that in the blank control group.

[0085] 2. LDH cytotoxicity test for cell mortality (tested according to the Beyotime Lactate Dehydrogenase Cytotoxicity Kit C0016)

[0086] Experimental methods:

[0087] (1) MKN45 cells in the logarithmic growth phase were inoculated into 24-well culture plates, with three replicate wells in each group. When the cells grew well, they were grouped and treated according to the above experimental scheme;

[0088] (2) One hour before the scheduled detection time, remove the cell culture plate from the cell culture incubator and add the LDH release reagent provided by the kit to the "sample maximum enzyme activity control well" at an amount of 10% of the original culture medium volume. After adding the LDH release reagent, repeatedly pipette several times to mix, and then continue to incubate in the cell culture incubator at 37°C in the dark for 1 hour;

[0089] (4) When the detection time is reached, the supernatant of each well is aspirated and centrifuged at 400 g for 5 min. After centrifugation, 120 μL of supernatant from each well is transferred to a new 96-well plate;

[0090] (5) According to the instructions of the LDH kit, add 60 μL of the prepared LDH working solution to each well and incubate at room temperature in the dark for 30 min;

[0091] (6) After incubation, use a microplate reader to measure the OD value of each well at 490 nm and calculate the cell death rate. Cytotoxicity or death rate (%) = (absorbance of treated sample - absorbance of sample control well) / (absorbance of maximum enzyme activity of cells - absorbance of sample control well) × 100.

[0092] Experimental results: According to Figure 4 It can be seen that the cell mortality rate in the gastric cancer stent group is higher than that in the blank control group.

[0093] 3. Calcein AM / PI live and dead cell double staining (follow the Bio-Tech Calcein / PI Cell Viability and Cytotoxicity Detection Kit C2015M)

[0094] Experimental methods:

[0095] (1) MKN45 cells in the logarithmic growth phase were digested with trypsin and then the cells were counted;

[0096] (2) Cells were seeded in a 24-well culture plate with a cover glass, with approximately 2 × 10 cells per well. 4 Each group of cells was divided into 3 replicate wells. When the cells grew well, the above experimental scheme was used for grouping and treatment.

[0097] (3) Discard the supernatant and prepare the staining working solution according to the instructions of the Cell Calcein AM / PI Live-Dead Double Staining Kit. Add 2502 μL of the working solution to each well and incubate at 4°C in the dark for 30 min.

[0098] (4) After the incubation, observe and take pictures under a fluorescence microscope (Calcein is green fluorescence, Ex / Em=494nm / 517nm; PI is red fluorescence, Ex / Em=535nm / 617nm).

[0099] The principle of this kit is that the two probes can detect intracellular esterase activity and cell membrane integrity respectively, thereby reflecting cell activity and cytotoxicity. Calcein AM stains live cells and shows green fluorescence, while propidium iodide (PI) stains dead cells and shows red fluorescence.

[0100] Experimental results: According to Figure 5 It can be seen that the cells in the blank control group did not die, and the cells showed uniform green fluorescence; the red fluorescence staining intensity of the cells in the gastric cancer stent group was significantly enhanced, the cell membrane was severely damaged, and the number of cell deaths was large.

[0101] 4. HE staining and cytopathological observation under an inverted microscope

[0102] Experimental results: According to Figure 6 It can be seen that the cells in the blank control group were normal in size, with clear boundaries, round or oval nuclei, and clear nuclear membranes and nucleoli.

[0103] according to Figure 7 It can be seen that in the gastric cancer stent group, large areas of cells were necrotic and detached, the boundaries were unclear, the boundaries of the nuclear membrane and nucleolus were unclear, and there were more nuclear condensation and dissolution.

[0104] Figure 6 and Figure 7 The multiple pictures in the figure represent cell staining images at different positions or under different magnifications, among which the upper left picture is a cell staining image magnified 10 times, the upper right picture is a cell staining image magnified 40 times, and the lower left and lower right pictures are both cell staining images magnified 20 times.

[0105] Therefore, from various anti-tumor experimental examination methods (CCK8 cell death rate, LDH cell survival rate, fluorescent staining dead cell display, conventional HE staining pathological examination), it is proved from multiple angles that under the current technical indicators of gastric cancer stents made of iodine 125 silk mantle, cancer cells can be effectively inhibited and killed. This proves the effectiveness of iodine 125 silk mantle.

[0106] The above are only preferred embodiments of the present invention and are not intended to limit the present invention. For those skilled in the art, the present invention may have various modifications and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. A method for preparing an iodine-based nuclide silk mantle, characterized in that: The following steps are involved: 1) Weaving the pretreated mulberry silk to obtain a filamentous mantle: 2) Label the filamentous mantle with iodine-125 to obtain an iodine-based radionuclide silk mantle.

2. The method for preparing the iodine-based nuclide silk mantle according to claim 1, characterized in that: In step 1), the weaving angle of the mulberry silk in a relaxed state is 5°-95°, and the number of strand ends is 4-24.

3. The method for preparing the iodine-based nuclide silk mantle according to claim 1, characterized in that: In step 1), the pretreatment of mulberry silk includes degumming, soaking, doubling, twisting and shaping.

4. The method for preparing the iodine-based nuclide silk mantle according to claim 1, characterized in that: The filamentous sleeve is one or more of a biliary stent sleeve, an intestinal stent sleeve, an esophageal stent sleeve and a ureteral stent sleeve, wherein the biliary stent sleeve has a long diameter of 3.0-3.5 cm and a wide diameter of 0.22 cm.

5. The method for preparing the iodine-based nuclide silk mantle according to claim 1, characterized in that: In step 2), the iodine-125 labeling step comprises: Place the filamentous mantle into a container, add iodine 125 solution, PBS solution and chloramine-T solution in sequence, and shake at room temperature for reaction; The reaction solution was collected, and the filamentous mantle membrane was cleaned by shaking with ultrapure water, and the cleaning solution was collected.

6. An iodine-based radionuclide silk mantle membrane produced by the method for preparing the iodine-based radionuclide silk mantle membrane as claimed in any one of claims 1 to 5.

7. A radioactive stent, characterized in that: It comprises the iodine-based radionuclide silk sheath and a stent tube as claimed in claim 6, wherein the iodine-based radionuclide silk sheath is detachably sheathed on the surface of the stent tube.

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