Magnetically-driven vascular intervention device and preparation method thereof

Abstract

The invention relates to the technical field of medical instruments, and provides a magnetic drive vascular intervention instrument and a preparation method thereof. According to the instrument provided by the invention, the continuous phases of the magnetic section and the non-magnetic section are both elastic polymer materials, and the magnetic section and the non-magnetic section can be stably connected. Micropores in micrometer scale are distributed in the outer surface and the interior of the main body of the instrument, and when the outer surface and the interior micropores of the instrument are infiltrated with lubricating materials, the vascular intervention instrument with the intrinsic super-smooth property can be obtained. The magnetic instrument provided by the invention has intrinsic super-lubricity, due to the special internal porous structure of the magnetic instrument, even if the lubricating material on the surface of the component is lost due to friction, the lubricating material in the internal micropores can also enable the component to have better super-lubricity, and the super-lubricity of the magnetic instrument cannot be lost due to contact friction in the use process; the device can be well matched with propelling systems of various guide wires or catheters, and damage to blood vessels in the operation process is reduced to the maximum extent.

Description

TECHNICAL FIELD

[0001] The application belongs to the technical field of medical devices, and particularly relates to a magnetically driven vascular interventional instrument and a preparation method thereof. BACKGROUND

[0002] Cardiovascular and cerebrovascular diseases represented by coronary heart disease and stroke are the first global killer disease, and vascular interventional surgery is one of the important means for diagnosing and treating such cardiovascular and cerebrovascular diseases. The current vascular interventional surgery has the pain points of high operation difficulty, high risk of blood vessel injury, need for doctors to bear radiation damage, and high learning cost. The remote magnetic control guide wire system can help doctors to accurately, safely and efficiently complete the vascular interventional surgery outside the radiation environment, and is a very promising alternative solution. As the core consumable of the remote magnetic control guide wire system, the magnetic guide wire can adapt to different angles of bending of the blood vessel under the precise control of the applied magnetic field, solve the problem of difficulty in passing through the tortuous part of the blood vessel with the traditional fixed-bend guide wire, and to a certain extent, reduce the risk of damage to the blood vessel wall by the guide wire. However, the guide wire will inevitably contact the blood vessel wall during the advancing process. In order to avoid damage to the blood vessel to the greatest extent, the magnetic guide wire itself should have excellent super-slip performance.

[0003] The surface hydrophilic coating is the most important scheme for improving the super-slip performance of the existing guide wire. This scheme realizes the activation of the hydrophilic coating by injecting heparinized saline into the guide wire sheath through a syringe when the guide wire is used. However, this scheme based on the hydrophilic coating has encountered many challenges in the practical application of the remote magnetic control guide wire system. Specifically, in the process of advancing the guide wire, the non-abrasive hydrophilic coating on the surface of the guide wire will be continuously lost in the process of contacting the blood vessel wall. In addition, in the remote magnetic control guide wire system, the steering and guiding of the guide wire are realized by the applied magnetic field, and the advancing / retracting of the guide wire is often realized by a propelling device based on the friction wheel / screw principle. Therefore, in the process of advancing and retracting the guide wire, the friction between the guide wire and the propelling device friction wheel / screw will also cause the loss of the coating on the surface of the guide wire. The loss of the hydrophilic coating will reduce the super-slip performance of the guide wire, increase the resistance of the guide wire in advancing in the blood vessel, and increase the risk of blood vessel spasm and damage. Further, serious loss of the hydrophilic coating of the guide wire will cause the guide wire to be unusable, so that the doctor needs to replace the guide wire temporarily during the operation, which will further increase the risk of blood vessel damage and increase the complexity of the operation. SUMMARY

[0004] The purpose of the present application is to provide a magnetically driven vascular interventional instrument and a preparation method thereof, aiming to solve the problem of easy loss of the super-slip coating of the existing magnetically driven vascular interventional instrument.

[0005] To achieve the above application purpose, the technical scheme adopted by the present application is as follows:

[0006] In a first aspect, this application provides a magnetically driven vascular interventional device, the magnetically driven vascular interventional device comprising a cylindrical body, the cylindrical body comprising: a non-magnetic segment and a magnetic segment coupled to one end of the non-magnetic segment;

[0007] The non-magnetic segment is made of a first elastic polymer material and a first lubricating material, and the magnetic segment is made of a second elastic polymer material, a magnetic material, and a second lubricating material. The magnetic segment is capable of bending in the direction of the applied magnetic field.

[0008] Both the non-magnetic segment and the magnetic segment have micropores. The first lubricating material fills the micropores of the non-magnetic segment, and the second lubricating material fills the micropores of the magnetic segment.

[0009] Secondly, this application provides a method for preparing a magnetically driven vascular interventional device, comprising the following steps:

[0010] Based on the application scenario requirements, construct three-dimensional models of the non-magnetic and magnetic segments of the magnetically driven vascular interventional device;

[0011] The initial non-magnetic segment was prepared by selective laser sintering printing using a first elastic polymer material as raw material.

[0012] Using a composite powder made from a mixture of a second elastic polymer material and a magnetic material as raw material, a second laser selective sintering printing process is performed at the end of the initial non-magnetic segment to prepare the initial magnetic segment, thus obtaining a shaped body.

[0013] The molded body is magnetized to obtain a magnetic molded body;

[0014] The magnetic molded body is immersed in a lubricating material to obtain the magnetically driven vascular interventional device.

[0015] The first aspect of this application provides a magnetically driven vascular interventional device. The non-magnetic segment is made of an elastic polymer, and the magnetic segment is made of a combination of magnetic and elastic polymer materials. The device has micron-scale micropores distributed on its outer surface and inside its main body. By immersing the device in a lubricating material, a vascular interventional device with intrinsic super-lubricating properties is obtained. When the device is solid and filamentous, it is a magnetic super-lubricating guidewire; when it is hollow and tubular, it is a magnetic super-lubricating catheter. The magnetic guidewire or catheter provided in this application possesses intrinsic super-lubricating properties and will not lose its super-lubricating properties due to contact friction during use. It can be well adapted to various guidewire or catheter advancement systems, minimizing damage to blood vessels during surgery. The intrinsic super-lubricating properties of the magnetic guidewire and catheter benefit from their special internal porous structure, eliminating the need for additional coating processes, simplifying the manufacturing process, and reducing costs. The magnetic and non-magnetic segments of the guidewire are integrally molded, with a consistent and stable connection between the two segments. Furthermore, the length of the magnetic segment of the guidewire can be customized according to the needs of the vascular structure, meeting the requirements of different application scenarios.

[0016] The second aspect of this application provides a method for fabricating a magnetically driven vascular interventional device using selective laser sintering (SLS 3D printing). This technique uses a laser to selectively bond polymer powder particles in a target area together in the form of sintered necks to form a component. Because the polymer particles are not completely melted and sintered during SLS printing, the printed component retains a large number of micropores. By introducing lubricating oil into the micropores inside the component, intrinsic super-lubricating properties can be imparted to the component. Even if the lubricating oil on the component surface is lost due to friction, the lubricating oil in its internal micropores can still ensure good super-lubricating properties. This method can solve the problem of easy loss of the hydrophilic coating on the surface of magnetic guidewires, endowing magnetic guidewires with durable super-lubricating properties, helping to reduce guidewire damage to blood vessels, and promoting the widespread application of remote magnetically controlled guidewire systems. Attached Figure Description

[0017] To more clearly illustrate the technical solutions in the embodiments of this application, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0018] Figure 1 This is a schematic diagram of the structure of the device provided in the embodiments of this application;

[0019] Figure 2 This is a diagram showing the vascular morphology adaptability of the magnetic segment turning radius of the device provided in the embodiments of this application;

[0020] Figure 3This is a microscopic mechanism diagram of the intrinsic superlubricating properties of the magnetic and non-magnetic segments of the guidewire provided in the embodiments of this application;

[0021] Figure 4 This is a schematic diagram of a method for activating the intrinsic superlubricity of the guidewire provided in an embodiment of this application;

[0022] Figure 5 This is a schematic diagram of the biocompatibility coating of magnetic materials provided in the embodiments of this application;

[0023] Figure 6 This is a schematic diagram of the structure of the catheter provided in the embodiment of this application;

[0024] Figure 7 This is a schematic diagram of the bending angle test of the guidewire provided in the embodiments of this application;

[0025] Figure 8 This is a schematic diagram of the guide wire roll angle test provided in Embodiment 2 of this application.

[0026] The following are the labeling elements in the figure:

[0027] 101 - Non-magnetic segment; 102 - Magnetic segment; 103 - Magnetic material; 104a - First elastic polymer material; 104b - Second elastic polymer material; 105a - First lubricating material; 105b - Second lubricating material; 105 - Micropores; 103a - Neodymium iron boron particles; 109 - Coating material;

[0028] 106-Guidewire; 107-Guidewire sheath; 108-Instrument; 110-Lubricating material;

[0029] 201 - Non-magnetic segment; 202 - Magnetic segment; 203 - Magnetic material; 204 - Elastic material; 205a - First lubricating material; 205b - Second lubricating material; 206 - Conduit seat. Detailed Implementation

[0030] To make the technical problems, technical solutions, and beneficial effects of this application clearer, the following detailed description is provided in conjunction with embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the scope of this application.

[0031] In this application, the term "and / or" describes the relationship between related objects, indicating that three relationships can exist. For example, A and / or B can represent: A existing alone, A and B existing simultaneously, or B existing alone. A and B can be singular or plural. The character " / " generally indicates that the preceding and following related objects have an "or" relationship.

[0032] In this application, "at least one" means one or more, and "more than one" means two or more. "At least one of the following" or similar expressions refer to any combination of these items, including any combination of single or multiple items. For example, "at least one of a, b, or c", or "at least one of a, b, and c", can both mean: a, b, c, ab (i.e., a and b), ac, bc, or abc, where a, b, and c can be single or multiple.

[0033] It should be understood that in the various embodiments of this application, the order of the above processes does not imply the order of execution. Some or all steps may be executed in parallel or sequentially. The execution order of each process should be determined by its function and internal logic, and should not constitute any limitation on the implementation process of the embodiments of this application.

[0034] The terminology used in the embodiments of this application is for the purpose of describing particular embodiments only and is not intended to be limiting of this application. The singular forms “a,” “the,” and “the” used in the embodiments of this application and the appended claims are also intended to include the plural forms unless the context clearly indicates otherwise.

[0035] The weights of the relevant components mentioned in the embodiments of this application can refer not only to the specific content of each component, but also to the proportional relationship between the weights of the components. Therefore, any scaling up or down of the content of the relevant components according to the embodiments of this application is within the scope disclosed in the embodiments of this application. Specifically, the mass described in the embodiments of this application can be a mass unit known in the chemical industry, such as μg, mg, g, or kg.

[0036] The terms "first" and "second" are used for descriptive purposes only, to distinguish objects, such as substances, from one another, and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. For example, without departing from the scope of the embodiments of this application, "first XX" may also be referred to as "second XX," and similarly, "second XX" may also be referred to as "first XX." Thus, features defined with "first" and "second" may explicitly or implicitly include one or more of that feature.

[0037] Interventional guidewires and catheters, as important medical devices, play an indispensable role in medical diagnosis and treatment. Since medical devices first come into contact with the human body through their surface and interaction with the biological environment, their surface properties directly affect or determine their functionality during use. Therefore, modifying the surface of medical devices with different functional coatings to change their surface properties and improve their biocompatibility and functionality has become a key aspect of modern medical device applications.

[0038] To reduce friction between devices and blood vessels, lubricating coatings are widely used on the surfaces of vascular interventional devices such as catheters, guidewires, and delivery systems. The coating adheres to the device surface through certain physical and / or chemical processes. However, these coated devices are susceptible to coating peeling, which can leave coating fragments in the patient's body, causing local tissue reactions and thrombosis, and even serious adverse events including pulmonary embolism, myocardial embolism, embolic stroke, tissue necrosis, and death.

[0039] Based on this, the first method of this application provides a magnetically driven vascular interventional device, such as... Figure 1 As shown, the magnetically driven vascular interventional device includes a cylindrical body comprising a non-magnetic segment 101 and a magnetic segment 102 coupled to one end of the non-magnetic segment 101. The non-magnetic segment 101 is made of a first elastic polymer material 104a and a first lubricating material 105a, and the magnetic segment 102 is made of a second elastic polymer material 104b, a magnetic material 103, and a second lubricating material 105b. The magnetic segment 102 is capable of bending in the direction of an applied magnetic field. Figure 3 As shown in Figures a and c, both the non-magnetic segment 101 and the magnetic segment 102 have micropores 105, such as... Figure 3 As shown in Figures c and d, the first lubricating material 105a fills the micropores 105 of the non-magnetic segment 101, as... Figure 3 As shown in Figures a and b, the second lubricating material 105b is filled in the micropores 105 of the magnetic segment 102.

[0040] The first aspect of this application provides a magnetically driven vascular interventional device. The non-magnetic segment 101 is made of an elastic polymer 104a, and the magnetic segment 102 is made of a magnetic material 103 and an elastic polymer material 104b. Since both the magnetic segment 102 and the non-magnetic segment 101 are made of elastic polymer materials, they can be stably connected. The outer surface and interior of the device are distributed with micron-scale micropores 105. When the outer surface and internal micropores of the device are wetted with a lubricating material, a vascular interventional device with intrinsic super-lubricating properties is obtained. The intrinsic super-lubricating performance of the magnetic device provided in this application is due to its special internal porous structure. Even if the lubricating material on the surface of the component is lost due to friction, the lubricating material in its internal micropores 105 can still give the component good super-lubricating properties. It will not lose its super-lubricating properties due to contact friction during use, and can be well adapted to various guidewire or catheter advancement systems, minimizing damage to blood vessels during surgery. The magnetic segment and the non-magnetic segment of the magnetic device are integrally molded, and the two segments are connected consistently and stably.

[0041] In some embodiments, the first and second elastic polymer materials each comprise thermoplastic polyurethane powder. The use of thermoplastic polyurethane for both elastic polymer materials, along with the identical connecting phase, allows for a more stable connection between the magnetic and non-magnetic segments.

[0042] In some embodiments, the particle size range of the thermoplastic polyurethane powder is 5–20 μm. As an example, the particle size range of the thermoplastic polyurethane powder includes, but is not limited to, any one or any two of the following: 5–10 μm, 7–12 μm, 9–14 μm, 11–16 μm, 13–18 μm, and 15–20 μm. Since the diameter of the guidewire or conduit is on the sub-millimeter scale, controlling the particle size of the thermoplastic polyurethane (TPU) powder within the above range allows for successful printing of the desired device while also ensuring a certain degree of surface smoothness. Using TPU powder with a larger particle size reduces the surface smoothness of the prepared guidewire or conduit; using TPU powder with a smaller particle size leads to significant agglomeration of powder particles, causing printing failure.

[0043] In some embodiments, the particle size of the thermoplastic polyurethane powder ranges from 10 to 15 μm. Controlling the particle size of the thermoplastic polyurethane powder within this range can make the printing process smoother and the resulting instrument surface smoother.

[0044] In some embodiments, the magnetic material includes neodymium iron boron powder.

[0045] In some embodiments, the particle size of the neodymium iron boron (NdFeB) powder ranges from 2 to 10 μm. Since the diameter of the guidewire or conduit is on the sub-millimeter scale, the NdFeB powder with a particle size range of 2 to 10 μm is selected in this embodiment. Controlling the particle size of the NdFeB powder within this range allows for the successful printing of the desired device while also ensuring a certain degree of surface smoothness.

[0046] In some embodiments, the particle size of the neodymium iron boron powder ranges from 4 to 6 μm. Controlling the particle size of the neodymium iron boron powder within this range can result in a smoother surface on the fabricated magnetically driven vascular interventional device.

[0047] In some embodiments, the remanence of NdFeB powder ranges from 800 to 900 mT. Remanence refers to the magnetization intensity retained by a magnetized object when it is no longer affected by an external magnetic field. When a magnet is magnetized to saturation by an external magnetic field, and the external magnetic field is gradually reduced to zero, a certain magnetic induction intensity will still be retained inside it; this retained magnetic induction intensity is called remanence. The unit of remanence is expressed in millitesla (mT). NdFeB powder with the above-mentioned remanence range has strong magnetism, which allows the prepared magnetic wires or conduits to produce the required turning angle under the action of a magnetic field.

[0048] In some embodiments, the remanence of the neodymium iron boron powder is in the range of 850–900 mT. Using neodymium iron boron powder within this range results in stronger magnetism, enabling the prepared magnetic wires or conduits to achieve the desired turning angle under the influence of a magnetic field.

[0049] In some embodiments, the first lubricating material and the second lubricating material each independently include at least one of medical dimethyl silicone oil and medical fluorosilicone oil.

[0050] Dimethyl silicone oil, also known as polydimethylsiloxane, is an organosilicon compound composed of polysiloxane alkyl groups. Medical-grade dimethyl silicone oil has good biocompatibility, is less likely to cause allergic reactions and tissue rejection, and also has good ductility and lubrication properties, which can impart good lubrication performance to medical devices.

[0051] In some embodiments, the viscosity range of medical dimethyl silicone oil is 1000–2000 cps, and the unit of viscosity is expressed in centipoise seconds (cps). The different viscosities of medical dimethyl silicone oil are mainly determined by the difference in guidewire wetting time and coefficient of friction. Using high-viscosity medical dimethyl silicone oil can give the guidewire better super-lubricating properties, but it also requires a longer wetting time.

[0052] Fluorosilicone oil is a polymer of dimethylsiloxane and trifluoropropylmethylsiloxane. Medical-grade fluorosilicone oil possesses excellent anticoagulant and biocompatibility. During vascular interventional procedures, heparin is commonly used for anticoagulation to prevent thrombosis at the site of arterial injury and on interventional instruments. However, high doses of heparin can induce bleeding, hypersensitivity reactions, thrombocytosis, dyspnea, and other adverse reactions. Using medical-grade fluorosilicone oil as a lubricant, the guidewire's ultra-slippery surface prevents water or blood from wetting the surface, thereby hindering protein and platelet adsorption and giving the guidewire excellent anticoagulant properties.

[0053] In some embodiments, the lubricating material includes a mixture of medical dimethyl silicone oil and medical fluorosilicone oil. Using the mixture as a lubricating material can enable the magnetic device proposed in this application to have both intrinsic super-lubricating properties and unique advantages in blood anticoagulation.

[0054] In some embodiments, when a mixture of medical-grade dimethyl silicone oil and medical-grade fluorosilicone oil is selected as the lubricant, the mass ratio of medical-grade dimethyl silicone oil to medical-grade fluorosilicone oil ranges from 1:2 to 2:1. As an example, the mass ratio of medical-grade dimethyl silicone oil to medical-grade fluorosilicone oil includes, but is not limited to, any one of 1:1, 1:1.5, 1:2, 2:1, 2:1.5, or any range between the two.

[0055] In some embodiments, the magnetic segment material further includes a coating material, which coats the outer surface of the magnetic material to form a coating layer. Because the intravascular environment places extremely high demands on the biocompatibility of vascular interventional devices, and magnetic materials pose a risk of corrosion and the release of harmful ions within the body, coating the outer surface of the magnetic material with a layer of coating material with good biocompatibility can improve the biocompatibility of the magnetic material.

[0056] In some embodiments, the coating material includes silica, and the thickness of the coating layer ranges from 20 to 100 nm. Magnetic material powders with a silica coating layer exhibit better biocompatibility. If the silica coating layer is too thin, the effect on improving biocompatibility is not significant; if the silica coating layer is too thick, it affects the magnetic response and mechanical properties of the substrate. Controlling the thickness of the silica coating layer within the above-mentioned range allows the magnetic material powder to have both better biocompatibility and suitable magnetic properties.

[0057] In some embodiments, the turning radius of the magnetic segment and the diameter of the proximal main blood vessel satisfy the following relationship: r ≥ 0.5R; where r is the turning radius of the magnetic segment and R is the diameter of the proximal main blood vessel. It should be noted that "proximal" and "distal" here are determined based on the distance of the blood vessel from the guidewire or catheter. Figure 2 As shown, the proximal main blood vessel refers to the main blood vessel closer to the guidewire, while the distal main blood vessel refers to the main blood vessel farther from the guidewire. Figure 2 As shown, when the magnetic segment undergoes a turning motion under the influence of a magnetic field, it bends into an arc, while the non-magnetic segment remains straight. A straight line L parallel to the non-magnetic segment is drawn through the endpoint D of the magnetic segment. The distance from the non-magnetic segment to the straight line L is the turning radius r of the magnetic segment. Specifically, when the guidewire turns from the main trunk vessel to a branch vessel, if the turning radius r of the magnetic segment is less than 0.5 times the characteristic size R of the proximal main trunk vessel, the guidewire cannot enter the branch vessel from the proximal main trunk vessel and will be pushed into the distal main trunk vessel. Only when the turning radius r of the magnetic segment is greater than 0.5 times the characteristic size R of the proximal main trunk vessel can the guidewire be delivered into the branch vessel. Combining the vascular anatomy and deformation simulation analysis of the magnetic device under different application scenarios, a geometric structure model library of the magnetic device is constructed. The turning radius of the magnetic segment can be determined based on the vascular anatomy, and the length of the magnetic segment can be determined based on the turning radius of the magnetic segment and the calibration / simulation results. To ensure that the magnetic segment of the device can smoothly enter the branch vessel after turning, the length of the magnetic segment of the magnetically driven vascular interventional device should match the diameter of the proximal main trunk vessel. Under the same magnetic field, the longer the magnetic segment, the larger its turning radius, which is suitable for proximal main blood vessels with larger diameters.

[0058] In some embodiments, the mass ratio of the second elastic polymer material to the magnetic material ranges from 40:60 to 70:30. As an example, the mass ratio of the second elastic material to the magnetic material includes, but is not limited to, any one of 40:60, 45:55, 50:50, 55:45, 60:40, 65:35, and 70:30, or any range between both. The mass ratio of the second elastic material to the magnetic material affects the magnetic and mechanical properties of the magnetic segment. Taking a magnetic guide wire as an example, the performance of a magnetic guide wire is generally evaluated by the bending angle of the wire under the same magnetic field. This parameter is mainly affected by the magnetic and mechanical properties of the printed magnetic guide wire. On the one hand, the higher the mass fraction of the magnetic material powder in the mixture of the magnetic material and the elastic polymer material, the stronger the magnetism of the printed magnetic guide wire, enabling it to interact with the driving magnetic field and generate a larger magnetic torque to bend the wire. On the other hand, increasing the proportion of magnetic material powder will make the magnetic guide wire itself harder, requiring a stronger magnetic torque to bend and deform the wire. When the magnetic powder content is low, the magnetic enhancement effect caused by its increased content dominates, and the bending angle of the guide wire increases rapidly with increasing magnetic powder content. When the magnetic powder content is high, the wire hardening effect caused by its increased content dominates, and the bending angle of the guide wire gradually decreases with increasing magnetic powder content. Controlling the mass ratio of the second elastic material to the magnetic material within the above range can result in a magnetic segment with better magnetic and mechanical properties.

[0059] In some embodiments, the bending angle range of the magnetically driven vascular interventional device is 0° to 150°. Because the magnetic vascular interventional device of this application embodiment has superior magnetic and mechanical properties, it thus possesses the aforementioned magnetically controlled bending angle range.

[0060] In some embodiments, the pore size of the micropores ranges from 1 to 10 μm. For example, the pore size includes, but is not limited to, any one of 1 μm, 2 μm, 3 μm, 4 μm, 5 μm, 6 μm, 7 μm, 8 μm, 9 μm, and 10 μm, or a range between any two. If the pore diameter is too large, it may result in insufficient structural strength of the guidewire; if the pore diameter is too small, it may cause the particles to stick together, losing its super-lubricating properties. Controlling the pore size of the micropores within the above range allows vascular interventional devices to have better mechanical and super-lubricating properties.

[0061] In some embodiments, the volume percentage of micropores in the columnar body is 1-5%. The pore size of the micropores is generally slightly smaller than the particle size of the magnetic material powder. The volume percentage of micropores in the columnar body can be detected macroscopically by the water ingress method and microscopically by micro-CT (three-dimensional X-ray imaging). In the embodiments of this application, the volume percentage of micropores can be controlled by adjusting the range of laser heating power density. Controlling the volume percentage of micropores in the columnar body within the above range allows the device to have both sufficient mechanical properties and sufficient space to accommodate lubricating material, thereby giving the device better superlubricating properties.

[0062] In some embodiments, the magnetically driven vascular interventional device is a guidewire, with a cylindrical body that is a solid filamentous body, the diameter of which ranges from 0.3 to 1 mm. When the device is solid filamentous, it is a magnetic super-slippery guidewire. Vascular interventional guidewires used in different applications have different geometric structures. The diameter range of vascular interventional guidewires used for angiography is generally 0.032 to 0.035 inches, while the diameter of microguidewires used for microcatheter guidance is mostly 0.014 inches. A three-dimensional model including the guidewire diameter can be constructed according to different needs.

[0063] In some embodiments, the magnetically driven vascular interventional device is a catheter, with a cylindrical body that is a hollow tubular body. The outer diameter of the hollow tubular body ranges from 0.5 to 1.7 mm, and the inner diameter ranges from 0.45 to 1.2 mm. When the device is hollow tubular, it is a magnetically super-lubricated catheter. Depending on the actual application scenario, catheters can be roughly divided into several categories, such as angiography catheters, guiding catheters, and microcatheters; the dimensions of different catheters vary considerably. The commonly used angiography catheter has a diameter of 5F (outer diameter 1.67 mm, inner diameter ~1.2 mm (the inner diameter of 5F catheters varies slightly between different manufacturers and for different purposes)). Guiding catheters are available in different specifications, such as 5F to 8F, depending on their application. The commonly used microcatheter has a distal diameter of 1.8F (outer diameter 0.6 mm, inner diameter 0.45 mm). In current clinical applications, the ability to change direction is mainly required for angiography catheters, while microcatheters advance along the pathway established by the microguidewire during use. Three-dimensional models including the inner and outer diameters of the catheter can be constructed according to different needs.

[0064] The second aspect of this application provides a method for preparing a magnetically driven vascular interventional device, comprising the following steps:

[0065] S1: Construct a three-dimensional model of the non-magnetic segment 101 and the magnetic segment 102 of the magnetically driven vascular interventional device according to the application scenario requirements;

[0066] S2: The initial non-magnetic segment is prepared by using the first elastic polymer material 104a as raw material and selective laser sintering printing.

[0067] S3: Using a composite powder made of a mixture of a second elastic polymer material 104b and a magnetic material 103 as raw material, a second laser selective sintering printing is performed at the end of the initial non-magnetic segment to prepare the initial magnetic segment and obtain the molded body;

[0068] S4: Magnetize the molded body to obtain a magnetic molded body;

[0069] S5: The magnetic molded body is immersed in a lubricating material to obtain a magnetically driven vascular interventional device.

[0070] The second aspect of this application provides a method for fabricating a magnetically driven vascular interventional device, employing Selective Laser Sintering (SLS) printing technology. SLS is a rapidly developing 3D printing technology in recent years, which uses a laser to selectively bond polymer powder particles in a target area together in the form of a sintering neck to form a component. For example... Figure 3 As shown in Figure a or c, because the polymer particles are not completely melted and sintered during the SLS printing process, a large number of micropores remain inside the printed component 105. Figure 3 As shown in Figures b or d, introducing lubricating material into the micropores 105 inside the component imparts intrinsic superlubricity to the component. Even if the lubricating material on the component surface is lost due to friction, the lubricating material in the micropores 105 inside the component can still give the component good superlubricity. The medical device prepared by this method has magnetic and non-magnetic segments. The magnetic segment enables the guidewire to have magnetically controlled bending function, which can be turned to the target branch blood vessel under the action of a magnetic field, and guide the non-magnetic segment smoothly into the branch blood vessel. Since the continuous phases of both the magnetic and non-magnetic segments are elastic polymer materials, the magnetic and non-magnetic segments can be stably connected. Existing vascular interventional magnetic guidewires mostly use high-temperature melting in the later stage or glue dispensing after assembly to connect the magnetic and non-magnetic segments. In comparison, the integrated molding scheme based on SLS 3D printing has a natural advantage in the stability and consistency of the connection between the magnetic and non-magnetic segments. The vascular interventional medical device prepared by this method not only has superlubricity but also magnetically controlled deformation capability, which can be used in remote magnetic control systems. The intrinsic super-lubricating property of magnetic instruments is due to their special internal porous structure, which does not require additional coating processes, making the processing simple and cost-effective.

[0071] Step S1:

[0072] Based on application scenario requirements, construct 3D models of the non-magnetic and magnetic segments of the magnetically driven vascular interventional device. Based on the requirements of the target application scenario, construct a 3D model of the required magnetic guidewire geometry. Vascular interventional guidewires used in different application scenarios have different geometric structures.

[0073] As an example, the diameter of guidewires used for angiography is generally in the range of 0.032–0.035 inches, while the diameter of microguidewires used for microcatheter guidance is mostly 0.014 inches. Furthermore, to ensure smooth entry of the magnetic guidewire into branch vessels after redirection, the length of the magnetic segment of the guidewire should match the diameter of the proximal main vessel. The principles for constructing guidewire and catheter models have been described in the first section and will not be repeated here.

[0074] Step S2:

[0075] The initial non-magnetic segment was prepared using a first elastic polymer material as raw material through selective laser sintering printing. Elastic polymer powder was loaded into an SLS 3D printer, and the initial non-magnetic segment was printed based on a three-dimensional model of the instrument's (such as a guidewire or catheter) geometry.

[0076] In some embodiments, the temperature range for the first laser selective sintering printing of the initial non-magnetic segment is 90–110 °C, and the laser power density ranges from 0.09 to 0.10 J / mm². 2 Laser power density is an important parameter describing the intensity of a laser beam; it refers to the laser power per unit area or volume. The relationship between laser power density (ED) and laser power (P) is shown in the following equation, where s is the laser scanning speed and v is the scanning distance.

[0077]

[0078] In SLS 3D printing, laser power density is the key process parameter. If the laser power density is too high, the polymer will melt and decompose; if the laser power density is too low, the polymer cannot be sintered and formed. Within the aforementioned laser density range, guidewires or catheters suitable for vascular intervention can be printed.

[0079] In some embodiments, the process parameters for preparing the initial non-magnetic segment by laser selective sintering printing are as follows: preheating temperature 85–95°C; processing temperature 95–105°C; laser energy density 0.1 J / mm². 2 Laser scanning speed: 3000 mm / s; printing layer thickness: 0.1 mm. The non-magnetic segments printed using the above process parameters exhibit superior performance.

[0080] Step S3:

[0081] A composite powder is obtained by mixing a second elastic polymer material and a magnetic material. The composite powder is then used as raw material to perform a second laser selective sintering printing at the end of the initial non-magnetic segment to prepare an initial magnetic segment. The initial magnetic segment and the initial non-magnetic segment are then integrally connected by laser selective sintering printing to obtain a molded body.

[0082] As an example, elastic polymer material and magnetic material powder are uniformly mixed at a certain mass ratio. This mixing can be done using a ball mill, with the milling speed and time depending on the actual production conditions. The milling speed includes, but is not limited to, 500–1000 rpm. The composite powder is then loaded into an SLS 3D printer, and the initial magnetic segment is printed directly above the initial non-magnetic segment.

[0083] In some embodiments, the temperature range for the second laser selective sintering printing is 90–110°C, and the laser power density ranges from 0.08 to 0.13 J / mm². 2 The process parameters for SLS 3D printing vary slightly depending on the proportion of the mixture of elastic polymer and magnetic materials. Higher magnetic material content results in a darker mixture, better laser absorption, and a lower required laser power density.

[0084] As an example, thermoplastic polyurethane (TPU) is selected as the elastic polymer material, and neodymium iron boron (NdFeB) is selected as the magnetic material. Taking the mass ratio of magnetic material in the composite powder as 40% to 70%, the printing parameters required for mixtures with different magnetic material contents in TPU / NdFeB mixture are shown in Table 1.

[0085] Table 1

[0086]

[0087] Step S4:

[0088] The molded body is magnetized to obtain a magnetic molded body.

[0089] In some embodiments, the magnetization process includes: placing the molded body into a pulse magnetizer to saturate the initial magnetic segment with magnetization, wherein the magnetization voltage range is 1000–2000V. The magnetization time of the pulse magnetizer is mainly determined by its discharge time; different magnetizers from different manufacturers have different discharge circuits, resulting in variations in discharge time. No specific limitation is made to the magnetization time here.

[0090] The initial magnetic segment is saturated with a pulse magnetizer at a voltage of 2000V, imparting axial remanence to the segment. Under the influence of an external magnetic field (either permanent magnet or electromagnetic), the magnetic segment of the guidewire or catheter can bend in the direction of the applied magnetic field, thus guiding the advancement of the guidewire or catheter. The magnetization direction of the magnetic segment can be designed using methods such as folded magnetization and point magnetization, allowing for more flexible control over the segment's direction.

[0091] Step S5:

[0092] The magnetic molded body is immersed in a lubricating material to obtain a magnetically driven vascular interventional device.

[0093] Magnetic guidewires or catheters fabricated using SLS 3D printing technology have uniformly distributed micropores inside. By immersing the magnetic guidewire or catheter in a lubricating material, a lubricating layer can be formed on both the internal micropores and the surface. Therefore, even if the lubricating layer on the surface of the device is lost due to friction, the internal lubricating material can still ensure sufficient super-lubricating properties.

[0094] As an example, it should be noted that the activation process of the intrinsic superlubricity of the guidewire is completed before its use. Figure 4 A detailed description of the process is provided. Before using the magnetic guidewire 106, the doctor only needs to inject lubricating material 110 into the guidewire sheath 107 via syringe 108 to activate the intrinsic super-lubricating properties of the guidewire. The operation is simple and convenient. The lubricating material 110 can be either a first lubricating material 105a or a second lubricating material 105b; the first lubricating material 105a and the second lubricating material 105b can be the same or different. This method can solve the problem of easy loss of the hydrophilic coating on the surface of the magnetic guidewire, giving the magnetic guidewire durable super-lubricating properties, helping to reduce guidewire damage to blood vessels, and promoting the widespread application of remote magnetically controlled guidewire systems.

[0095] Since the magnetic guide wire or conduit prepared by SLS 3D printing technology in this application embodiment naturally has micron-scale micropores 105 inside, by immersing the magnetic guide wire in lubricating oil, the micropores inside can be fully coated with lubricating material, thereby activating the intrinsic super-lubricating properties of the guide wire.

[0096] In some embodiments, such as Figure 5 As shown, the magnetic segment material also includes a coating material 109 coated on the surface of the magnetic material 103. The preparation method of coating material 109 on the surface of the magnetic material 103 includes the following steps: dispersing magnetic material powder in ethanol solvent. Then, adding ammonium hydroxide or ammonia while stirring, and then adding tetraethyl orthosilicate (TEOS) and stirring for 8-16 hours to generate coating material 109.

[0097] The intravascular environment places extremely high demands on the biocompatibility of guidewires or catheters. Before guidewire or catheter fabrication, NdFeB magnetic powder 103a is pretreated using a sol-gel method, such as... Figure 5 As shown, the surface of the NdFeB magnetic powder 103a obtained by the treatment is coated with a layer of nanoscale SiO2 coating material 109. This coating treatment can ensure that the prepared magnetic wire has good biocompatibility.

[0098] As an example: 40g of neodymium iron boron (NdFeB) powder was dispersed in 1000ml of ethanol and stirred to avoid precipitation. Then, while stirring, 60ml of 29% ammonium hydroxide (ammonia) was slowly added to the mixture, followed by 2ml of tetraethyl orthosilicate (TEOS). The mixture was stirred at room temperature for 12 hours, and then washed several times with acetone after the reaction to obtain NdFeB powder with a silica coating.

[0099] In some embodiments, the thickness of the silicon dioxide coating layer ranges from 20 to 100 nm.

[0100] In the sol-gel method, SiO2 microspheres of different sizes can be prepared by changing reaction parameters, such as altering the volume ratio of tetraethyl orthosilicate (TEOS) to solvent, and the concentration and amount of ammonia added. Under the same conditions, higher ammonia concentration and higher TEOS concentration result in a thicker SiO2 coating layer. Controlling the thickness of the silica coating layer within the above range can effectively improve the biocompatibility of magnetic materials.

[0101] As an example, a magnetically driven vascular interventional guidewire was prepared according to the preparation method of the second aspect, such as... Figure 1 As shown, the device includes a solid core wire body, which has a non-magnetic segment 101 and a magnetic segment 102. The non-magnetic segment 101 is made of a first elastic material 104a and a first lubricating material 105a. The magnetic segment 102 is disposed at the end of the non-magnetic segment 101 and integrally connected to the end of the non-magnetic segment 101. The magnetic segment 102 is made of a second elastic material 104b, a magnetic material 103, and a second lubricating material 105b. The magnetic segment 102 has axial remanence and can be bent in the direction of an applied magnetic field. Both the non-magnetic segment 101 and the magnetic segment 102 have micropores 105. The first lubricating material 105a is filled in the micropores 105 of the non-magnetic segment, and the second lubricating material 105b is filled in the micropores 105 of the magnetic segment.

[0102] This application discloses a method for fabricating an intrinsically superlubricated magnetic guidewire based on SLS 3D printing technology. This unique intrinsic superlubricating property gives the magnetic guidewire a natural advantage in various guidewire advancement devices. During the guidewire advancement process, there is significant contact friction between the device body and the guidewire. Traditional magnetic guidewires experience substantial loss of their hydrogel coating during this process, affecting their superlubricating properties. However, the intrinsically superlubricated magnetic guidewire prepared using the method described in this application maintains its superlubricating properties. This intrinsic superlubricating property minimizes the risk of damage to blood vessels during guidewire advancement, reducing the risk of surgical complications.

[0103] In vascular interventional procedures, catheter guidance is typically achieved via guidewires. However, in locations such as the aortic arch, the catheter needs to first enter branch vessels like the internal carotid artery before guiding the guidewire, necessitating a guiding capability from the catheter. In actual clinical practice, surgeons use catheters with different pre-bent structures, employing techniques like catheter trapping, to deliver the catheter to the branch vessels. This process is complex and difficult, requiring numerous pre-bent catheters with varying structures and is prone to vascular damage. Remotely magnetically controlled adjustable bending catheter systems represent a promising alternative to address these issues. Similar to the aforementioned remotely magnetically controlled guidewire systems, the use of hydrophilic coated magnetic catheters in remotely magnetically controlled adjustable bending catheter systems also faces the problem of easily losing the ultra-slippery coating on the catheter surface, leading to catheter-related vascular damage.

[0104] Based on this, as an example, a magnetically driven vascular interventional catheter is prepared according to the preparation method of the second aspect, such as... Figure 6 As shown, the device includes a hollow tubular body with a non-magnetic segment 201 and a magnetic segment 202. The non-magnetic segment 201 is made of a first elastic material 204a and a first lubricating material 205a. The magnetic segment 202 is disposed at the end of the non-magnetic segment 201 and integrally connected to the end of the non-magnetic segment 201. The magnetic segment 202 is made of a second elastic material 204b, a magnetic material 203, and a second lubricating material 205b. The magnetic segment 202 is capable of bending in the direction of an applied magnetic field. Both the non-magnetic segment 201 and the magnetic segment 202 have micropores 205. The first lubricating material 205a fills the micropores 205 of the non-magnetic segment, and the second lubricating material 205b fills the micropores 205 of the magnetic segment.

[0105] Based on laser selective area sintering printing technology, the macroscopic and microscopic structures of the intrinsically superlubricated magnetic conduits prepared are as follows: Figure 6 As shown, the catheter is composed of a non-magnetic segment 201, a magnetic segment 202, and a catheter seat 203. The non-magnetic segment 201 is fabricated from elastic polymer powder 204a using SLS 3D printing technology, and the magnetic segment 202 is fabricated from a mixture of magnetic material 203 and elastic polymer powder 204b using SLS 3D printing technology. The detailed process of catheter fabrication is consistent with that of the aforementioned guidewire fabrication process. The printed catheter has micron-scale micropores distributed inside. By immersing the catheter in a lubricating material, a vascular interventional catheter with intrinsic super-lubricating properties can be obtained. Similar to the activation method of the super-lubricating properties of the aforementioned guidewire, the intrinsic super-lubricating properties of this catheter are also activated before use. The activation process is similar to... Figure 4 similar.

[0106] The detailed process for fabricating the catheter in this embodiment is consistent with the aforementioned guidewire fabrication process. By replacing the guidewire geometric model in the second aspect's fabrication method with a catheter geometric model, a magnetic catheter with intrinsic super-lubricating properties can be fabricated. The printed catheter has micron-scale micropores distributed inside. Immersing this catheter in a lubricating material yields a vascular interventional catheter with intrinsic super-lubricating properties. This intrinsic super-lubricating property can minimize damage to blood vessels during catheter advancement.

[0107] The following description is based on specific embodiments.

[0108] Example 1

[0109] This application provides a magnetically driven, ultra-slippery guidewire for vascular intervention, which has the following characteristics: Figure 1 The illustrated structure includes a solid core wire body, which has a non-magnetic segment and a magnetic segment; the magnetic segment is located at the end of the non-magnetic segment and is integrally connected to the end of the non-magnetic segment. Wherein:

[0110] The non-magnetic segment is made of TPU with a particle size of 10μm; the diameter of the non-magnetic segment is 0.5mm.

[0111] The magnetic segment is made of TPU with a particle size of 10μm and neodymium iron boron with a particle size of 5μm; the magnetic segment is 10mm long and 0.5mm in diameter.

[0112] Its preparation method includes the following steps:

[0113] S1: Construct 3D models of the non-magnetic and magnetic segments of the instrument according to the application scenario requirements;

[0114] S2: TPU polymer powder is loaded into the SLS 3D printer, and the non-magnetic section of the guide wire is printed based on the 3D model of the guide wire's geometry. The SLS 3D printing process parameters are as follows: preheating temperature 90℃; processing temperature 100℃; laser energy density 0.1J / mm². 2 Laser scanning speed: 3000 mm / s; Printing layer thickness: 0.1 mm;

[0115] S3: NdFeB powder and TPU powder are uniformly mixed at a mass ratio of 4:6. The TPU / NdFeB mixture is then loaded into the SLS 3D printer, and the magnetic section of the guide wire is printed directly above the non-magnetic section. The SLS 3D printing process parameters are as follows: preheating temperature 90℃; processing temperature 100℃; laser energy density 0.125J / mm². 2 Laser scanning speed: 3000 mm / s; Printing layer thickness: 0.1 mm.

[0116] S4: Use a pulse magnetizer to saturate the magnetic segment of the guide wire with a magnetization voltage of 2000V, giving the guide wire axial residual magnetism;

[0117] S5: The magnetic guidewire prepared using SLS 3D printing technology naturally contains micron-sized micropores. By immersing the magnetic guidewire in dimethyl silicone oil, the internal micropores and outer surface can be fully coated with dimethyl silicone oil, thereby activating the intrinsic superlubricating properties of the guidewire. The dimethyl silicone oil used is a medical-grade dimethyl silicone oil with a viscosity of 1000 cps.

[0118] Example 2

[0119] This application provides a magnetically driven vascular interventional super-slippery guidewire. This embodiment is basically the same as Embodiment 1, except that in this embodiment, NdFeB powder and TPU powder are used to prepare the magnetic segment at a mass ratio of 6:4. The laser energy density in step S3 is 0.10 J / mm². 2 .

[0120] Example 3

[0121] This application provides a magnetically driven vascular interventional super-slippery guidewire. This embodiment is basically the same as Embodiment 1, except that in this embodiment, NdFeB powder and TPU powder are used to prepare the magnetic segment at a mass ratio of 7:3. The laser energy density in step S3 is 0.09 J / mm². 2 .

[0122] Example 4

[0123] This embodiment provides a magnetically driven vascular interventional super-slippery guidewire. This embodiment is basically the same as Embodiment 2, except that in this embodiment, the surface of NdFeB powder is coated with a SiO2 coating layer.

[0124] The preparation method of NdFeB powder with SiO2 coating is as follows: 40g of NdFeB particles were dispersed in 1000ml of ethanol and stirred vigorously at 1500rpm to avoid precipitation. Then, 60ml of 29% ammonium hydroxide (ammonia water) was slowly added to the mixture, followed by 2ml of tetraethyl orthosilicate (TEOS). The mixture was stirred at room temperature for 12 hours, and then washed several times with acetone after the reaction. Finally, the suspension was vacuum filtered to obtain NdFeB powder with SiO2 coating, the thickness of which ranged from 20 to 30nm.

[0125] Example 5

[0126] This embodiment provides a magnetically driven vascular interventional super-slippery guidewire. This embodiment is basically the same as Embodiment 2, except that the lubricating material in this embodiment is medical fluorosilicone oil.

[0127] Example 6

[0128] This embodiment provides a magnetically driven, highly slippery vascular interventional catheter, which has the following characteristics: Figure 6 The illustrated structure includes a hollow tubular body, which has a non-magnetic segment and a magnetic segment; the magnetic segment is located at the distal end of the non-magnetic segment and is integrally connected to the distal end of the non-magnetic segment. Wherein:

[0129] The non-magnetic segment is made of TPU with a particle size of 10μm; the outer diameter of the non-magnetic segment is 1.6mm and the inner diameter is 1mm.

[0130] The magnetic segment is made of TPU with a particle size of 10μm and neodymium iron boron with a particle size of 5μm; the magnetic segment is 10mm long, with an outer diameter of 1.6mm and an inner diameter of 1mm.

[0131] The preparation method is the same as in Example 2.

[0132] Performance testing

[0133] (1) Under different driving magnetic fields, the guidewires or catheters from Examples 1 to 6 were subjected to bending angle tests. The bending angle was measured using optical imaging, and the definition of the bending angle is as follows: Figure 7 As shown. Where B represents the magnetic field, the direction of the straight arrow pointing to B indicates the direction of the magnetic field, L1 represents a tangent to the magnetic segment 102 drawn through endpoint D, and L2 represents the extension of the non-magnetic segment 101, with a bending angle... The angle between L1 and L2, and the bending angle results are recorded in Table 2.

[0134] Table 2

[0135]

[0136] As can be seen from the data in Table 2, the magnetic guide wire has the optimal bending angle when the mass ratio of NdFeB magnetic powder to TPU powder is 6:4.

[0137] (2) The guide wire from Example 2 was used for super-lubricating performance testing. The super-lubricating performance of the specimen was determined by measuring the rolling angle of the specimen. The closer the rolling angle was to 0°, the better the super-lubricating performance. Figure 8 The diagram illustrates the method for measuring the roll-off angle. The roll-off angle refers to the critical angle α formed by the inclined surface and the horizontal plane when a droplet just begins to roll on the inclined surface. The roll-off angle is denoted by WSA. The roll-off angle test results of the guidewire in Example 2 show that its roll-off angle WSA = 1.41°, indicating that the water droplet can roll on the inclined surface when the guidewire is inclined at 1.41°, proving that the guidewire of this embodiment has super-slippery properties.

[0138] The above description is merely a preferred embodiment of this application and is not intended to limit this application. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of this application should be included within the protection scope of this application.

Claims

1. A magnetically driven vascular interventional device, characterized in that, The magnetically driven vascular interventional device includes a cylindrical body, the cylindrical body comprising: a non-magnetic segment and a magnetic segment coupled to one end of the non-magnetic segment; The non-magnetic segment is made of a first elastic polymer material and a first lubricating material, and the magnetic segment is made of a second elastic polymer material, a magnetic material, and a second lubricating material. The magnetic segment is capable of bending in the direction of the applied magnetic field. Both the non-magnetic segment and the magnetic segment have micropores. The first lubricating material fills the micropores of the non-magnetic segment, and the second lubricating material fills the micropores of the magnetic segment.

2. The magnetically driven vascular interventional device as described in claim 1, characterized in that, The first elastic polymer material and the second elastic polymer material each comprise thermoplastic polyurethane powder; and / or, The magnetic material includes neodymium iron boron powder; and / or, The first lubricating material and the second lubricating material each include at least one of medical dimethyl silicone oil and medical fluorosilicone oil.

3. The magnetically driven vascular interventional device as described in claim 2, characterized in that, The particle size range of the thermoplastic polyurethane powder is 5–20 μm; and / or, The particle size range of the neodymium iron boron powder is 2 to 10 μm, and the remanence range of the neodymium iron boron powder is 800 to 900 mT.

4. The magnetically driven vascular interventional device as described in claim 1, characterized in that, The material of the magnetic segment also includes a coating material, which coats the outer surface of the magnetic material to form a coating layer.

5. The magnetically driven vascular interventional device as described in claim 4, characterized in that, The coating material includes silicon dioxide, and the thickness of the coating layer ranges from 20 to 100 nm.

6. The magnetically driven vascular interventional device as described in claim 1, characterized in that, The turning radius of the magnetic segment and the diameter of the proximal main blood vessel satisfy the following relationship: r ≥ 0.5R; where r is the turning radius of the magnetic segment and R is the diameter of the proximal main blood vessel; and / or, The mass ratio of the second elastic polymer material to the magnetic material ranges from 40:60 to 70:30; and / or, The bending angle range of the magnetically driven vascular interventional device is 0° to 150°.

7. The magnetically driven vascular interventional device according to any one of claims 1 to 6, characterized in that, The pore size ranges from 1 to 10 μm; and / or, the volume percentage of the micropores in the columnar body is 1% to 5%.

8. The magnetically driven vascular interventional device according to any one of claims 1 to 6, characterized in that, The magnetically driven vascular interventional device is a guidewire, and the cylindrical body is a solid filamentous body with a diameter ranging from 0.3 to 1 mm; or, The magnetically driven vascular interventional device is a catheter, and the columnar body is a hollow tubular body with an outer diameter ranging from 0.5 to 1.7 mm and an inner diameter ranging from 0.45 to 1.2 mm.

9. A method for preparing a magnetically driven vascular interventional device, characterized in that, Includes the following steps: Based on the application scenario requirements, construct three-dimensional models of the non-magnetic and magnetic segments of the magnetically driven vascular interventional device; The initial non-magnetic segment was prepared by selective laser sintering printing using a first elastic polymer material as raw material. Using a composite powder made from a mixture of a second elastic polymer material and a magnetic material as raw material, a second laser selective sintering printing process is performed at the end of the initial non-magnetic segment to prepare an initial magnetic segment, thereby obtaining a shaped body. The molded body is magnetized to obtain a magnetic molded body; The magnetic molded body is immersed in a lubricating material to obtain the magnetically driven vascular interventional device.

10. The method for preparing the magnetically driven vascular interventional device as described in claim 9, characterized in that, The temperature range for the first laser selective sintering printing is 90–110℃, and the laser power density ranges from 0.09 to 0.10 J / mm². 2 , and / or The temperature range for the second laser selective sintering printing is 90–110℃, and the laser power density ranges from 0.08 to 0.13 J / mm². 2 .

11. The method for preparing the magnetically driven vascular interventional device as described in claim 9 or 10, characterized in that, The magnetization process includes: placing the molded body into a pulse magnetizer to saturate the initial magnetic segment with magnetization, wherein the magnetization voltage range is 1000-2000V.

12. The method for preparing the magnetically driven vascular interventional device as described in claim 9 or 10, characterized in that, The material of the magnetic segment also includes a coating material coating the surface of the magnetic material. The preparation method of coating the magnetic material includes the following steps: dispersing the magnetic material powder in an ethanol solvent, adding ammonia water, and then adding tetraethyl orthosilicate and stirring for 8 to 16 hours to generate the coating material.

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