Antibacterial bionic silicone airway stent and preparation method thereof

Abstract

The present invention discloses an antibacterial bionic silicone airway stent and a preparation method thereof. The specific method is to use a molding process to obtain a silicone airway stent with a bionic buffer node and a nail-shaped anti-skid structure; use a hydrothermal method to obtain an antibacterial super-hydrophilic coating; and then, use a dip-coating process to coat the super-hydrophilic coating on the inner and outer surfaces of the stent to obtain a silicone airway stent with buffering, tracking fixation and antibacterial properties. First, a buffer node that mimics the original tracheal structure is set on the stent body to improve the extensibility and buffering of the stent, so as to reduce the foreign body sensation and discomfort generated by the stent during normal breathing or neck movement; secondly, a developable nail-shaped anti-skid structure is set on the outer wall of the stent, which can provide tracking positioning and fixation at the same time; thirdly, the antibacterial super-hydrophilic coating has the effects of antibacterial and anti-inflammatory and preventing mucus blockage, and can effectively alleviate the inflammatory symptoms caused by stent intervention.

Description

Technical Field

[0001] The present invention relates to the technical field of medical devices, and in particular to an antibacterial bionic silicone airway stent and a preparation method thereof. Background Art

[0002] Airway stenosis caused by focal or systemic inflammation, dynamic collapse and malignant tumors is a common clinical disease. Severe stenosis can cause respiratory failure and even endanger life. Airway stents can quickly expand the trachea after implantation, and are a quick and effective treatment to relieve breathing difficulties in patients with airway stenosis. However, at the same time, a series of complications will occur after stent implantation, among which displacement, secondary stenosis, mucus blockage, inflammatory response and irritation are relatively common problems, which also bring huge burdens to patients and the entire medical system.

[0003] In response to the above problems, some solutions have been taken. For example, the DUMON stent effectively solves the problem of stent displacement by designing a smooth anti-slip structure on the outer wall of the stent, which lays the foundation for the development of airway stents. However, there is still a lot of room for improvement in the complications caused by stent intervention. For example, inflammatory reactions and mucus blockage, currently commonly used are anti-inflammatory drugs or enhanced atomization therapy to humidify the airway to promote expectoration. For example, the patent (201810488480.9) fills drugs in the stent to relieve inflammatory symptoms, but the control of drug sustained release rate is also a difficult process to solve. At the same time, the high frequency of atomization therapy is also likely to burden the patient's economy. Relevant studies have shown that superhydrophilic coatings can also play an anti-adhesion role due to their own wettability characteristics, and are expected to be widely used in biological implants and medical devices. In addition, the original trachea includes cartilage rings, annular ligaments and tracheal muscle structures, and their synergistic effect makes the trachea have longitudinal extensibility, and during normal breathing or neck movement, the length of healthy trachea in adults can be extended by 20%, and that in newborns can be extended by 46%. However, existing brackets are generally not deformable, such as patent (202110098372.2), which results in a large difference in matching degree between them and natural gas pipes.

[0004] The present invention sets a segmented buffer section imitating the trachea structure on the stent body, so that the stent has a certain degree of extensibility and buffering, so as to fit normal breathing or neck movement and reduce the foreign body sensation and discomfort caused by the bending of the stent; a developing anti-displacement structure is set on the outer wall of the stent to provide tracking positioning and fixation; the antibacterial super-hydrophilic coating can provide antibacterial and anti-inflammatory effects and prevent mucus blockage. Therefore, the present invention can improve the comfort and authenticity of the airway stent to a certain extent, and can effectively reduce the complications caused by stent intervention. Summary of the invention

[0005] One of the purposes of the present invention is to provide an antibacterial bionic silicone airway stent in order to solve the above technical problems.

[0006] The second object of the present invention is to provide a method for preparing the above-mentioned antibacterial bionic silicone airway stent.

[0007] The present invention is achieved through the following technical solutions:

[0008] An antibacterial bionic silicone airway stent and a preparation method thereof are carried out according to the following steps:

[0009] (1) Parameter design of bionic silicone airway stent

[0010] The bionic concept was introduced, and an airway stent mold with a buffer section and a nail-shaped groove structure that imitated the original airway structure was obtained according to the design drawings.

[0011] To better realize the present invention, further, the airway stent parameters are designed as follows: the total length is 20~70 mm, the wall thickness is 1~2.5 mm, and the outer diameter is 10~20 mm; the number of buffer sections is set to 0~5 sections, the spacing between each section is 1~25 mm, each section is provided with 1~4 sections, the height of each section is 1~8 mm, the outer diameter of each section is 12~25 mm, and the wall thickness is 0.5~2.5 mm; the diameter of the nail-shaped anti-slip structure is 0.8~5.0 mm, and the wall thickness is 1~2.5 mm.

[0012] (2) Preparation of uncoated biomimetic silicone airway stent

[0013] Medical silicone and developer are mixed evenly and added to the designated nail-shaped groove position of the mold; then an appropriate amount of medical silicone is injected into the mold cavity and molded at 135-195 °C for 180-360 s to obtain an uncoated silicone airway stent with a buffer joint and a developable nail-shaped anti-slip structure.

[0014] In order to better realize the present invention, further, the added developer is medical barium sulfate, and the mixing mass ratio of medical silica gel to barium sulfate is 2-25.

[0015] To better implement the present invention, further, the Shore hardness of the medical silicone is 50-85 HA.

[0016] In the embodiments of the present invention, unless otherwise specified, the Shore hardness of the medical silicone is 70 HA.

[0017] (3) Preparation of antibacterial super-hydrophilic coating

[0018] The hydrothermal method is used to heat the zwitterion with a double bond structure, the silane coupling agent with a double bond structure and the initiator in a water bath, and after a certain period of time, the antibacterial agent is added, and the stirring is continued to finally obtain the antibacterial super hydrophilic coating.

[0019] To better implement the present invention, further, the zwitterion with a double bond structure is a combination of one or more of a carboxylate type, a sulfonate type, a sulfate ester type and a phosphate ester type.

[0020] To better implement the present invention, further, the silane coupling agent containing a double bond structure is a combination of one or more vinyl silane coupling agents.

[0021] To better implement the present invention, further, the initiator is a combination of one or more of an azo initiator and a persulfate initiator.

[0022] To better realize the present invention, further, the antibacterial agent is one or a combination of nano silver, nano magnesium oxide, nano zinc oxide and nano titanium dioxide.

[0023] To better realize the present invention, further, the mass ratio of zwitterion to silane coupling agent is 0.5-5, and the amount of antibacterial agent added is 2%-6% of the amount of zwitterion added.

[0024] In the embodiments of the present invention, unless otherwise specified, the zwitterion is [2-(methacryloyloxy)ethyl]dimethyl-(3-sulfonic acid propyl)ammonium hydroxide (SBMA).

[0025] In the embodiments of the present invention, unless otherwise specified, the silane coupling agent is vinyltrimethoxysilane (YHD-171).

[0026] In the embodiments of the present invention, unless otherwise specified, the initiator is 2,2-azobis(2-methylpropylimidamide) dihydrochloride (AIBA).

[0027] In the embodiments of the present invention, unless otherwise specified, the antibacterial agent is nanosilver with a size of 15-20 nm.

[0028] (4) Preparation of antibacterial biomimetic silicone airway stent

[0029] The airway stent was dipped in the antibacterial super-hydrophilic coating for 10-30 min and dried at 70-90 °C for 2-8 h to obtain a bionic silicone airway stent with antibacterial properties.

[0030] Beneficial effects of the present invention

[0031] (1) The bionic silicone airway stent provided by the present invention has a stent body provided with a buffer joint that mimics the structure of the original trachea so that the stent can fit the changes of the original trachea during normal breathing and neck movement, and reduce the foreign body sensation caused by the bending of the stent.

[0032] (2) The silicone airway stent provided by the present invention has a developable anti-slip structure on its outer wall that can provide stent position tracking and positioning functions, while also enhancing the friction between the stent and the inner wall of the airway, effectively reducing the risk of suffocation caused by stent displacement.

[0033] (3) The antibacterial bionic silicone airway stent provided by the present invention has an antibacterial super-hydrophilic coating which has the effects of antibacterial, anti-inflammatory and preventing mucus blockage, and can effectively alleviate the discomfort symptoms after stent intervention. BRIEF DESCRIPTION OF THE DRAWINGS

[0034] Figure 1 Schematic diagram of the antibacterial biomimetic silicone airway stent.

[0035] Figure 2 Schematic diagram of the state changes of the silicone airway stent buffer section. DETAILED DESCRIPTION

[0036] The present invention will be further described in detail below in conjunction with specific embodiments, which are provided to explain the present invention rather than to limit it.

[0037] Preparation of antibacterial biomimetic silicone airway stent

[0038] Embodiment 1:

[0039] According to the design drawings, the bionic silicone airway stent mold was obtained. The parameters of the obtained stent template were: total length 30 mm, wall thickness 1 mm, outer diameter 16 mm; the diameter of the spike-shaped anti-slip structure was 3 mm, and the wall thickness was 1 mm; the number of buffer sections was set to 2, the spacing between each section was 7 mm, each section had 2 sections, each section had a height of 2.25 mm, each section had an outer diameter of 18 mm, and a wall thickness of 1 mm. Medical silicone and developer were mixed evenly at a mass ratio of 15:1 and added to the designated nail-shaped groove position of the mold; an appropriate amount of medical silicone was injected into the mold cavity and molded at 175 ℃ for 270 s, and finally an uncoated silicone airway stent with buffer sections and developable spike-shaped anti-slip structure was obtained.

[0040] 2 g SBMA and 1 g YHD-171 were dissolved in water and initiator was added and then heated in a water bath at 60 °C for 2 h. Subsequently, 0.08 g nanosilver was added to the solution and continued to be heated in a water bath for 1 h, and finally an antibacterial superhydrophilic coating was obtained. The airway stent sample was dipped in the superhydrophilic coating for 20 min and dried at 80 °C for 4 h to obtain a bionic silicone airway stent with antibacterial properties.

[0041] Embodiment 2:

[0042] According to the design drawings, the bionic silicone airway stent mold was obtained. The parameters of the obtained stent template were: total length 70 mm, wall thickness 2.5 mm, outer diameter 20 mm; the diameter of the spike-shaped anti-slip structure was 0.8 mm, and the wall thickness was 2.5 mm; the number of buffer sections was set to 5, the spacing between each section was 5 mm, each section had 1 section, each section had a height of 8 mm, each section had an outer diameter of 25 mm, and a wall thickness of 2.5 mm. Medical silicone and developer were mixed evenly in a mass ratio of 2:1 and added to the designated nail-shaped groove position of the mold; an appropriate amount of medical silicone was injected into the mold cavity and molded at 195 ℃ for 180 s, and finally an uncoated silicone airway stent with buffer sections and developable spike-shaped anti-slip structure was obtained.

[0043] 0.5 g SBMA and 1 g YHD-171 were dissolved in water and initiator was added and then heated in a water bath at 75 °C for 1 h. Then 0.03 g nanosilver was added to the solution and continued to be heated in a water bath for 1 h, and finally an antibacterial superhydrophilic coating was obtained. The airway stent sample was dipped in the superhydrophilic coating for 30 min and dried at 90 °C for 2 h to obtain a bionic silicone airway stent with antibacterial properties.

[0044] Embodiment 3:

[0045] According to the design drawings, the bionic silicone airway stent mold was obtained. The parameters of the obtained stent template were as follows: total length of 20 mm, wall thickness of 1 mm, outer diameter of 10 mm; diameter of the spike-shaped anti-slip structure of 5 mm, wall thickness of 1 mm; the number of buffer sections was set to 1 segment, each segment had 4 segments, each segment had a height of 1 mm, each segment had an outer diameter of 12 mm, and a wall thickness of 0.5 mm. Medical silicone and developer were mixed evenly at a mass ratio of 25:1 and added to the designated nail-shaped groove position of the mold; an appropriate amount of medical silicone was injected into the mold cavity and molded at 135 ℃ for 360 s, and finally an uncoated silicone airway stent with buffer sections and developable spike-shaped anti-slip structure was obtained.

[0046] 5 g SBMA and 1 g YHD-171 were dissolved in water and initiator was added and then heated in a water bath at 50 °C for 5 h. Subsequently, 0.1 g nanosilver was added to the solution and continued to be heated in a water bath for 1 h, and finally an antibacterial super-hydrophilic coating was obtained. The airway stent sample was dipped in the super-hydrophilic coating for 10 min and dried at 70 °C for 8 h to obtain a bionic silicone airway stent with antibacterial properties.

[0047] Embodiment 4:

[0048] According to the design drawings, the bionic silicone airway stent mold was obtained. The parameters of the obtained stent template were: total length 30 mm, wall thickness 1 mm, outer diameter 16 mm; the diameter of the spike-shaped anti-slip structure was 3 mm, and the wall thickness was 1 mm; the number of buffer sections was set to 3 sections, the spacing between each section was 3 mm, each section had 4 sections, each section had a height of 1.5 mm, each section had an outer diameter of 18 mm, and a wall thickness of 1 mm. Medical silicone and developer were mixed evenly at a mass ratio of 15:1 and added to the designated nail-shaped groove position of the mold; an appropriate amount of medical silicone was injected into the mold cavity and molded at 175 ℃ for 270 s, and finally an uncoated silicone airway stent with buffer sections and developable spike-shaped anti-slip structure was obtained.

[0049] 2 g SBMA and 1 g YHD-171 were dissolved in water and initiator was added and then heated in a water bath at 60 °C for 2 h. Then 0.08 g nanosilver was added to the solution and continued to be heated in a water bath for 1 h, finally obtaining an antibacterial super-hydrophilic coating. The airway stent sample was dipped in the super-hydrophilic coating for 20 min and dried at 80 °C for 4 h to obtain a bionic silicone airway stent with antibacterial properties.

[0050] Embodiment 5:

[0051] According to the design drawings, the bionic silicone airway stent mold was obtained. The parameters of the obtained stent template were: total length 30 mm, wall thickness 1 mm, outer diameter 16 mm; the diameter of the spike-shaped anti-slip structure was 3 mm, and the wall thickness was 1 mm; the number of buffer sections was set to 2, the spacing between each section was 7 mm, each section had 2 sections, each section had a height of 2.25 mm, each section had an outer diameter of 18 mm, and a wall thickness of 1 mm. Medical silicone and developer were mixed evenly at a mass ratio of 15:1 and added to the designated nail-shaped groove position of the mold; an appropriate amount of medical silicone was injected into the mold cavity and molded at 175 ℃ for 270 s, and finally an uncoated silicone airway stent with buffer sections and developable spike-shaped anti-slip structure was obtained.

[0052] 1 g SBMA and 1 g YHD-171 were dissolved in water and initiator was added and then heated in a water bath at 60 °C for 2 h. Then 0.04 g nanosilver was added to the solution and continued to be heated in a water bath for 1 h, and finally an antibacterial super-hydrophilic coating was obtained. The airway stent sample was dipped in the super-hydrophilic coating for 30 min and dried at 80 °C for 2 h to obtain a bionic silicone airway stent with antibacterial properties.

[0053] Comparative Example 1:

[0054] According to the design drawings, the bionic silicone airway stent mold was obtained. The parameters of the obtained stent template were: total length 30 mm, wall thickness 1 mm, outer diameter 16 mm; the diameter of the spike-shaped anti-slip structure was 3 mm, and the wall thickness was 1 mm. Medical silicone and developer were mixed evenly at a mass ratio of 15:1 and added to the designated nail-shaped groove position of the mold; an appropriate amount of medical silicone was injected into the mold cavity and molded at 175 ℃ for 270 s, and finally an uncoated silicone airway stent with a buffer joint and a developable spike-shaped anti-slip structure was obtained.

[0055] 2 g SBMA and 1 g YHD-171 were dissolved in water and initiator was added and then heated in a water bath at 60 °C for 2 h. Then 0.08 g nanosilver was added to the solution and continued to be heated in a water bath for 1 h, finally obtaining an antibacterial super-hydrophilic coating. The airway stent sample was dipped in the super-hydrophilic coating for 20 min and dried at 80 °C for 4 h to obtain a bionic silicone airway stent with antibacterial properties.

[0056] Comparative Example 2:

[0057] According to the design drawings, the bionic silicone airway stent mold was obtained. The parameters of the obtained stent template were: total length 30 mm, wall thickness 1 mm, outer diameter 16 mm; the diameter of the spike-shaped anti-slip structure was 3 mm, and the wall thickness was 1 mm; the number of buffer sections was set to 2, the spacing between each section was 7 mm, each section had 2 sections, each section had a height of 2.25 mm, each section had an outer diameter of 18 mm, and a wall thickness of 1 mm. Medical silicone and developer were mixed evenly at a mass ratio of 15:1 and added to the designated nail-shaped groove position of the mold; an appropriate amount of medical silicone was injected into the mold cavity and molded at 175 ℃ for 270 s, and finally an uncoated silicone airway stent with buffer sections and developable spike-shaped anti-slip structure was obtained.

[0058] Comparative Example 3:

[0059] According to the design drawings, the bionic silicone airway stent mold was obtained, and the parameters of the obtained stent template were: total length 30 mm, wall thickness 2.5 mm, outer diameter 16 mm; the diameter of the spike-shaped anti-slip structure was 3 mm, and the wall thickness was 1 mm. Medical silicone and developer were mixed evenly at a mass ratio of 15:1 and added to the designated spike-shaped groove position of the mold; an appropriate amount of medical silicone was injected into the mold cavity and molded at 175 ℃ for 270 s, and finally an uncoated silicone airway stent with a buffer joint and a developable spike-shaped anti-slip structure was obtained.

[0060] Comparative Example 4:

[0061] According to the design drawings, the bionic silicone airway stent mold was obtained. The parameters of the obtained stent template were as follows: total length 80 mm, wall thickness 3 mm, outer diameter 20 mm; the diameter of the spike-shaped anti-slip structure was 1 mm, and the wall thickness was 2.5 mm; the number of buffer sections was set to 6, the spacing between each section was 8 mm, each section had 2 sections, each section had a height of 2 mm, each section had an outer diameter of 25 mm, and a wall thickness of 2.5 mm. Medical silicone and developer were mixed evenly at a mass ratio of 15:1 and added to the designated nail-shaped groove position of the mold; an appropriate amount of medical silicone was injected into the mold cavity and molded at 175 ℃ for 270 s, and finally an uncoated silicone airway stent with buffer sections and developable spike-shaped anti-slip structure was obtained.

[0062] The performance test results of the antibacterial bionic silicone airway stent are shown in Table 1.

[0063] The anti-migration force and radial support force of the antibacterial bionic silicone airway stent are measured using a digital force gauge. The specific test method is as follows: fix the airway stent on the tensile strength tester, insert the stent into the Teflon clamp, use a push gauge to move the stent to 5 cm opposite the Teflon clamp, and measure the anti-migration force data of the stent; place the stent on the test platform, attach the measuring pressure measuring element to the surface of the stent, measure the force until the stent diameter is reduced by 50%, and measure the radial support force data.

[0064] The elongation at break and tensile strength tests were conducted in accordance with the requirements of GB / T528-2009 "Determination of tensile stress-strain properties of vulcanized rubber or thermoplastic rubber". The contact angle data of the super-hydrophilic coating was measured using a contact angle meter. The percentage of bacterial reduction was calculated by calculating the ratio of the number of surviving colonies before and after, which was used to detect the antibacterial activity of the super-hydrophilic coating against Staphylococcus aureus. The degree of inflammation and cytotoxicity tests were conducted in accordance with the requirements of GB / T16886.6 "Biological Evaluation of Medical Devices: Local Reaction Test after Implantation" and GB / T16886.5 "Biological Evaluation of Medical Devices: In Vitro Cytotoxicity Test".

[0065] Table 1 Performance test results of antibacterial bionic silicone airway stent.

[0066]

[0067] From the results of each embodiment, the antibacterial bionic silicone airway stent has good biocompatibility. Among them, the comparative example 1 does not have a buffer node, and its elongation at break and tensile strength are poor compared with those of Example 1. The comparison shows that the buffer node can improve the extensibility of the stent; the comparative example 2 is not dip-coated with an antibacterial super-hydrophilic coating, and its hydrophilicity and antibacterial properties are poor, and mild inflammation occurs; in the comparative example 3, neither the buffer node nor the antibacterial super-hydrophilic coating is set, but the overall wall thickness of the stent is increased, and its radial support force is better; the design of the stent parameters in the comparative example 4 exceeds the set range, and its comprehensive performance is quite different from the optimal example. In summary, the setting of the local bionic buffer node structure can improve the extensibility of the stent to a certain extent, and the parameter design of the buffer node has a great influence on the comprehensive performance of the stent; the proportion of the super-hydrophilic coating and the adjustment of the amount of antibacterial agent added also have a great influence on the hydrophilicity and antibacterial strength of the stent; the increase in the wall thickness of the stent can improve the radial support force of the stent.

[0068] The results show that the antibacterial bionic silicone airway stent designed in the present invention can improve the extensibility of the airway stent to a certain extent, and has the advantage of alleviating complications caused by stent intervention.

[0069] Although the content of the present invention has been described in detail through the above preferred embodiments, it should be appreciated that the above description should not be considered as a limitation of the present invention. After reading the above content, it will be apparent to those skilled in the art that various modifications and substitutions of the present invention will occur. Therefore, the protection scope of the present invention should be limited by the appended claims.

Claims

1. A method for preparing an antibacterial bionic silicone airway stent, which is mainly characterized in that it is composed of a silicone airway stent body and an antibacterial super-hydrophilic coating, the stent body is a tubular structure, a segmented buffer section is arranged on the stent body according to the original airway structure, the outer wall of the stent is provided with a developable nail-shaped anti-slip structure, and the stent is coated with an antibacterial super-hydrophilic coating as a whole; The specific preparation method is: (1) The airway stent mold consists of 1 to 5 sections of buffer sections and nail-shaped groove structures that imitate the original airway structure; (2) Mix the medical silica gel and the developer evenly and then add them to the designated nail-shaped groove position of the mold; (3) injecting medical silicone into the mold cavity and subjecting the mold to a compression molding process at 135-195°C to obtain an uncoated silicone airway stent with a Shore hardness of 50-85 HA and a buffer joint and a developable nail-shaped anti-slip structure; (4) Using a hydrothermal method, the zwitterion and silane coupling agent with double bond structures are heated in a water bath and an appropriate amount of initiator is added. Then, after reacting for 1 to 5 hours, an antibacterial agent is added and stirring is continued to obtain an antibacterial superhydrophilic coating. (5) The superhydrophilic coating was applied to the main body of the silicone stent by a dip coating process for 10 to 30 min, and a bionic silicone airway stent with antibacterial properties was obtained by a drying process.

2. The method for preparing an antibacterial bionic silicone airway stent according to claim 1 is characterized in that the spacing between each buffer section in the stent in step (1) is 1-25 mm, each section is provided with 1-4 sections, each section has a height of 1-8 mm, an outer diameter of each section is 12-25 mm, and a wall thickness of 0.5-2.5 mm; the diameter of the nail-shaped anti-slip structure is 0.8-5.0 mm, and the wall thickness is 1-2.5 mm.

3. The method for preparing an antibacterial bionic silicone airway stent according to claim 1, characterized in that the developer in step (2) is medical barium sulfate, wherein the mixing mass ratio of medical silicone to medical barium sulfate is 2-25.

4. The method for preparing an antibacterial biomimetic silicone airway stent according to claim 1, characterized in that the molding process time in step (3) is 180 to 360 seconds.

5. The method for preparing an antibacterial bionic silicone airway stent according to claim 1, characterized in that the airway stent in step (3) has a total length of 20 to 70 mm, a wall thickness of 1 to 2.5 mm, and an outer diameter of 10 to 20 mm.

6. The method for preparing an antibacterial biomimetic silicone airway stent according to claim 1, characterized in that the zwitterion with a double bond structure in step (4) is a combination of one or more of carboxylate type, sulfonate type, sulfate ester type and phosphate ester type; and the silane coupling agent with a double bond structure is a combination of one or more of vinyl silane coupling agents.

7. The method for preparing an antibacterial bionic silicone airway stent according to claim 1, characterized in that the initiator in step (4) is a combination of one or more of an azo initiator and a persulfate initiator; and the antibacterial agent is a combination of one or more of nano-silver, nano-magnesium oxide, nano-zinc oxide and nano-titanium dioxide.

8. The method for preparing an antibacterial biomimetic silicone airway stent according to claim 1, characterized in that the mass ratio of the zwitterion to the silane coupling agent added in step (4) is 0.5-5, the amount of the antibacterial agent added is 2%-6% of the amount of the zwitterion added, and the reaction temperature is 50-75°C.

9. The method for preparing an antibacterial biomimetic silicone airway stent according to claim 1, characterized in that the drying process time in step (5) is 2 to 8 hours and the drying process temperature is 70 to 90°C. 10 . The antibacterial bionic silicone airway stent prepared according to the method for preparing the antibacterial bionic silicone airway stent according to any one of claims 1 to 9 .

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