CN120114730A

CN120114730A - Intracranial thrombus aspiration catheter and preparation method thereof

Info

Publication number: CN120114730A
Application number: CN202510607876.0A
Authority: CN
Inventors: 黄奉康; 袁文文; 毛明攀; 吴艳
Original assignee: Sichuan Action Medical Technology Co ltd
Current assignee: Sichuan Action Medical Technology Co ltd
Priority date: 2025-05-13
Filing date: 2025-05-13
Publication date: 2025-06-10
Anticipated expiration: 2045-05-13
Also published as: CN120114730B

Abstract

The invention discloses an intracranial thrombus aspiration catheter and a preparation method thereof, belonging to the technical field of medical appliances, the catheter comprises a PTFE lining, a reinforcing layer (comprising a coil layer and a braiding layer), an outer plastic layer with a sectional design, a platinum iridium alloy developing ring and a coating. The preparation method comprises extrusion of PTFE lining, winding of coil, covering of a braiding layer, molding of a segmented plastic layer, embedding and fixing of a developing ring, coating treatment and surface functionalization. Compared with the prior art, the invention obviously improves the adhesive force of the coating, prevents falling off, enhances the surface hydrophilicity, reduces thrombus adhesion and improves the blood compatibility and the operation performance by optimizing the formula and the process of the coating. In addition, the multi-layer structural design improves the flexibility, kink resistance and collapse resistance of the catheter, and ensures the stability and effectiveness of the catheter in complex vascular environments.

Description

Intracranial thrombus aspiration catheter and preparation method thereof

Technical Field

The invention relates to the technical field of medical appliances, in particular to an intracranial thrombus aspiration catheter and a preparation method thereof.

Background

Intracranial thrombus aspiration catheters are a critical medical instrument for treating acute ischemic stroke. Acute ischemic stroke is caused by thrombosis or embolism in intracranial large vessels (such as internal carotid artery, middle cerebral artery, basilar artery and vertebral artery), resulting in ischemia of brain tissue, and in severe cases, permanent brain injury and even death can occur. Timely restoration of blood flow is critical to treatment, and intracranial thrombus aspiration catheters have become an important treatment modality to remove thrombus by mechanical aspiration.

Although the existing intracranial thrombus aspiration catheter achieves a certain effect in clinical application, technical bottlenecks and defects still exist, and further application and development of the intracranial thrombus aspiration catheter are limited. First, existing catheters have insufficient coating adhesion and are prone to shedding in complex vascular environments, which not only affects catheter performance, but may also cause complications such as thrombus residue or vascular injury. Secondly, the catheter surface has poor hydrophilicity, so that thrombus adhesion is difficult to effectively reduce and blood compatibility is improved, the thrombus adhesion is increased, the suction effect is affected, and the treatment success rate is further reduced. In addition, the intracranial blood vessel has a complex structure, the flexibility and the kink resistance of the existing catheter are insufficient, the smooth passage in the blood vessel and the reaching of the target position are difficult to ensure, the catheter can be blocked or kinked in the blood vessel, and the treatment effect is affected. Finally, during the aspiration process, the catheter needs to bear a certain negative pressure, and the insufficient collapse resistance of the existing catheter may cause deformation or blockage of the catheter, reduce aspiration efficiency, and increase pain and treatment risk of the patient.

Some improvements in the prior art, while solving the above problems to some extent, still present significant limitations. For example, some coating techniques, while improving adhesion, tend to sacrifice hydrophilicity or other properties, resulting in increased thrombus adhesion, which in turn affects the effectiveness of the catheter. In addition, existing catheters often employ a single material or a simple composite material, which is difficult to meet the combined requirements of flexibility, kink resistance and collapse resistance, and this single or simple combination of materials limits the performance of the catheter in complex vascular environments. Moreover, although some improvements improve catheter performance, the process is complex, the cost is high, and the large-scale production and clinical application are not facilitated, so that the improvements are difficult to popularize widely in the actual medical environment, and the application range and the popularization degree of the improvements are limited.

Chinese patent application publication No. CN118490306a discloses a thrombus aspiration catheter and an interventional medical device comprising a tube body, a thrombus aspiration channel and a drug delivery channel. The thrombus sucking channel extends from the distal end to the proximal end, and the medicine conveying channel extends from the proximal end to the distal end, and is respectively provided with a sucking inlet, a medicine outlet, a sucking outlet and a medicine input port. Although the technique realizes the dual functions of thrombus aspiration and drug delivery, the problems of insufficient coating adhesion and poor surface hydrophilicity are not solved, so that the performance of the catheter in a complex vascular environment is limited, and the aspiration effect and the blood compatibility can be affected.

Chinese patent application publication No. CN117731363a discloses an embolic pull through and a thrombus aspiration catheter, including a catheter, a Y-type hemostatic valve, and an embolic pull through. The embolism dredging device comprises a dredging element, a supporting element and a limiting locking element, and can be used for mashing, softening and dredging thrombus blocked in a catheter without retracting the catheter for flushing. Although this technique solves the problem of thrombus blockage in the catheter, it does not involve improvements in the flexibility, kink resistance and collapse resistance of the catheter, and does not optimize the coating properties, so the overall performance in a complex vascular environment remains to be improved.

Disclosure of Invention

Aiming at the defects of the prior art, the invention provides an improved intracranial thrombus aspiration catheter and a preparation method thereof, and aims to solve the problems of insufficient coating adhesion, poor surface hydrophilicity, insufficient flexibility and kink resistance, insufficient collapse resistance and the like in the prior art.

In order to achieve the above object, the present invention adopts the following technical scheme:

An intracranial thrombus aspiration catheter comprising a multi-layer structure from inside to outside:

(a) A PTFE liner, which is positioned at the innermost layer of the catheter and is made of Polytetrafluoroethylene (PTFE) material, and is used for reducing thrombus adhesion and providing a smooth cavity;

(b) The coil is positioned outside the PTFE lining and is formed by a stainless steel or nickel-titanium alloy wound spring, so that the collapse resistance is provided;

(c) Braiding, namely braiding a net structure by stainless steel wires, wherein part of the net structure is covered on the outer side of the coil and is used for improving kink resistance;

(d) The plastic layer is designed in a sectional way, the near end adopts high-hardness polyurethane, the far end gradually changes into low-hardness polyurethane, and the hardness gradient is realized through a coextrusion or sectional injection molding process;

(e) The developing ring is made of platinum iridium alloy and is embedded in the catheter;

(f) And the coating is positioned on the outermost layer of part of the catheter and comprises at least one of glycerin polyacrylate, polyurethane or polyethylene glycol as a base material.

Further, a preparation method of the intracranial thrombus aspiration catheter comprises the following steps:

step 1, preparing a PTFE lining by adopting an extruder to obtain the PTFE lining;

step 2, winding nickel-titanium alloy wires on the outer surface of the PTFE lining to obtain a coil;

Step 3, braiding the stainless steel wires into a net shape by adopting a braiding machine, partially covering the coil, and heating to obtain braiding;

Step 4, coating polyurethane on a near-end high-hardness section, switching to soft polyurethane on a far-end low-hardness section, and continuously reducing the hardness through a gradual transition area to obtain a plastic layer;

Step 5, embedding a platinum iridium alloy developing ring in the middle section of the catheter, and fixing by adopting pulse laser spot welding;

And 6, dissolving glycerol polyacrylate in acetone, adding vinyl trimethoxy silane, stirring and filtering to obtain an inner layer solution, adding a substrate substance and a glycidyl ether compound into acetone, adding a cross-linking agent and a photoinitiator, stirring and filtering to obtain a surface layer solution, coating the inner layer solution on the surface of a part of catheter, drying, coating the surface layer solution, and performing ultraviolet curing to obtain the intracranial thrombus aspiration catheter.

Preferably, the preparation method of the intracranial thrombus aspiration catheter comprises the following steps:

step 1, preparing a PTFE lining by adopting an extruder, wherein the extrusion temperature is 380-400 ℃, and the inner diameter is controlled to be 0.05-0.1mm, so as to obtain the PTFE lining;

Step 2, winding nickel-titanium alloy wires with the diameter of 0.05-0.1mm, the spiral spacing of 0.3-0.5mm, the winding speed of 200-300rpm and the tension of 5-10N on the outer surface of the PTFE lining by a spring winding machine;

Step 3, braiding, namely braiding stainless steel wires with the diameter of 0.02-0.04mm into a net shape by adopting a 16-shaft braiding machine at the density of 60-80PPI, partially covering a coil layer, wherein the braiding angle is 30-45 degrees, and heating for 5-15 seconds at the temperature of 280-300 ℃;

Step 4, a plastic layer is formed by coating Shore D60-70 polyurethane on a near-end high-hardness section by adopting a double-screw extruder, wherein the extrusion temperature is 200-220 ℃, and the hardness is continuously reduced by switching Shore A80-90 soft polyurethane on a far-end low-hardness section through a 5-10cm gradual transition region;

step 5, embedding a platinum iridium alloy developing ring at the position 4-6cm away from the head end in the middle section of the catheter, fixing by adopting pulse laser spot welding, wherein the wavelength of the pulse laser is 1000-1100nm, the power is 10-30W, and the plastic layer is prevented from being damaged by heat;

and 6, coating, namely dissolving 4-7 parts by weight of glycerol polyacrylate in 30-50 parts by weight of acetone, stirring at room temperature for 20-40 minutes, adding 1.5-2 parts by weight of vinyltrimethoxysilane, continuously stirring for 0.5-2 hours, filtering through pores of 0.1-0.3 mu m to obtain an inner layer solution, adding 10-20 parts by weight of a base substance and 2-4 parts by weight of a glycidyl ether compound into 80-100 parts by weight of acetone, stirring at 40-60 ℃ for 30-50 minutes until the base substance and the glycidyl ether compound are completely dissolved, adding 1-2 parts by weight of a cross-linking agent and 1-2 parts by weight of a photoinitiator, stirring for 20-40 minutes, filtering through pores of 0.1-0.3 mu m to obtain a surface layer solution, uniformly coating the inner layer solution on part of the surface of a catheter, drying in a 50-70 ℃ oven, coating the surface layer solution thereon, and curing by ultraviolet light to obtain the intracranial thrombus aspiration catheter.

The substrate material in the step 6 is at least one of polyurethane and polyethylene glycol.

The glycidyl ether compound in the step 6 is at least one of 1, 4-butanediol diglycidyl ether and trimethylolpropane triglycidyl ether.

The cross-linking agent in the step 6 is at least one of trimethylolpropane trimethacrylate and pentaerythritol tetraacrylate.

The photoinitiator in the step 6 is at least one of 2-hydroxy-2-methyl-1-phenylpropion and 1-hydroxycyclohexyl phenyl ketone.

In the step 6, the thickness of the inner layer is 3-5 mu m, and the thickness of the surface layer is 5-7 mu m.

And the ultraviolet light curing in the step 6 is performed for 2-5 minutes by using 300-350nm ultraviolet light.

The glycerol polyacrylate is used as a main component of the inner layer coating, and provides good substrate adhesion and biocompatibility.

Vinyl trimethoxy silane is used as a coupling agent, so that the binding force between the inner layer coating and the substrate is enhanced, and the adhesive force and durability of the coating are improved.

Polyurethane or polyethylene glycol is used as a substrate of the outer coating, the polyurethane provides good mechanical properties and flexibility, and the polyethylene glycol endows the coating with excellent hydrophilicity and biocompatibility.

The glycidyl ether compound reacts with polyurethane or polyethylene glycol to form a network structure, so that the stability and the hydrophilicity of the coating are enhanced.

The cross-linking agent further enhances the network structure of the coating and improves the mechanical properties and durability of the coating.

The photoinitiator initiates a crosslinking reaction under the irradiation of ultraviolet light, so that the curing of the coating is promoted, and the rapid forming and the stability of the coating are ensured.

Compared with the prior art, the method has the following beneficial effects:

1) The invention obviously improves the coating adhesive force of the intracranial thrombus suction catheter by optimizing the coating formula and the process, effectively prevents the coating from falling off, and ensures the stability and the durability of the catheter in the use process.

2) The intracranial thrombus suction catheter has good surface hydrophilicity, greatly reduces thrombus adhesion and improves blood compatibility and operation performance.

Drawings

FIG. 1 is a schematic diagram of a structural model of an intracranial thrombus aspiration catheter of the present invention;

the multi-layer structure of the intracranial thrombus aspiration catheter is as follows in sequence from inside to outside:

a PTFE liner, which is the innermost layer of the catheter and is made of Polytetrafluoroethylene (PTFE) material, and is used for reducing the adhesion between thrombus and the inner wall of the catheter and providing a smooth cavity for facilitating the smooth passing of the thrombus in the suction process;

2. the coil is positioned at the outer side of the PTFE lining and is formed by a stainless steel or nickel-titanium alloy wound spring, and the main function of the coil layer is to provide collapse resistance and ensure that the catheter can keep the shape and the structure during the use process;

3. Braiding, namely braiding a net-shaped structure formed by braiding stainless steel wires, wherein the net-shaped structure partially covers the outer side of a coil layer, and the design of the layer is to promote the kink resistance of a catheter so that the navigation of the catheter in a blood vessel is smoother;

4. The plastic layer is an outer layer of the catheter, adopts a sectional design, adopts a high-hardness polyurethane material at the proximal end part to provide enough supporting force, adopts low-hardness polyurethane at the distal end to increase the flexibility of the catheter, and realizes the gradient change of hardness from the proximal end to the distal end through a coextrusion or sectional injection molding process;

5. The developing ring is made of platinum iridium alloy and embedded in the catheter, and plays a developing role in the medical imaging process, so that doctors can monitor the position of the catheter in real time;

6. A coating layer located on the outermost layer of a part of the catheter, wherein the base material of the coating layer at least comprises one of glycerol polyacrylate, polyurethane or polyethylene glycol, and the coating layer has the function of further improving the surface characteristics of the catheter, such as hydrophilicity, biocompatibility and the like, so as to improve the performance and safety of the catheter in medical operation;

This multi-layer structural design aims to improve the operability of the intracranial thrombus aspiration catheter in a complex vascular environment, while ensuring its stability and effectiveness.

Detailed Description

The main material sources are as follows:

Shore D65 polyurethane, germany, model D64P477, brand Henschel.

Shore A85 soft polyurethane, germany, TPU A85P 4394, brand number Henschel.

Glycerol polyacrylate, product number k25, guangdong beautifier Co.

Polyurethane, brand s95A, manufacturer (origin) Germany Basiff.

Polyethylene glycol, PEG-600, brand name, korean music day.

The other raw materials in the examples and comparative examples of the present invention are all commercially available products.

A structural model diagram of the intracranial thrombus aspiration catheter prepared by the examples and the comparative examples of the present invention is shown in FIG. 1.

Example 1

The preparation method of the intracranial thrombus aspiration catheter comprises the following steps:

Step 1, preparing a PTFE lining by adopting an extruder, wherein the extrusion temperature is 380 ℃, and the inner diameter is controlled to be 0.08mm, so as to obtain the PTFE lining;

Step 2, winding nickel-titanium alloy wires with the diameter of 0.06mm, the spiral pitch of 0.4mm and the winding speed of 260rpm on the outer surface of the PTFE lining by a spring coiling machine, and controlling the tension to be 8N;

Step 3, braiding, namely braiding stainless steel wires with the diameter of 0.03mm into a net shape by adopting a 16-shaft braiding machine at the density of 70PPI, partially covering a coil layer, wherein the braiding angle is 40 DEG;

Step 4, a plastic layer is formed by coating Shore D65 polyurethane on a near-end high-hardness section by adopting a double-screw extruder, wherein the extrusion temperature is 210 ℃, and the hardness is continuously reduced through an 8cm gradual transition zone by switching the near-end low-hardness section into Shore A85 soft polyurethane;

Step 5, a developing ring, namely embedding a platinum iridium alloy developing ring (containing 90wt% of platinum and 10wt% of iridium) at the position 5 cm from the head end in the middle section of the catheter, fixing by adopting pulse laser spot welding, wherein the wavelength of the pulse laser is 1064 nm, the power is 20W, and the plastic layer is prevented from being damaged by heat;

And 6, coating, namely dissolving 6 parts by weight of glycerol polyacrylate in 40 parts by weight of acetone, stirring at room temperature for 30 minutes, adding 1.8 parts by weight of vinyltrimethoxysilane, continuously stirring for 1 hour, filtering through 0.2 mu m pores to obtain an inner layer solution, adding 15 parts by weight of polyurethane and 3 parts by weight of trimethylolpropane triglycidyl ether into 90 parts by weight of acetone, stirring at 50 ℃ for 40 minutes until the mixture is completely dissolved, adding 1.5 parts by weight of pentaerythritol tetraacrylate and 1.5 parts by weight of 2-hydroxy-2-methyl-1-phenylpropione, stirring for 30 minutes, filtering through 0.2 mu m pores to obtain a surface layer solution, uniformly coating the inner layer solution on part of the surface of the catheter, drying the catheter at 60 ℃, coating the surface layer solution on the catheter, and curing the catheter with 310nm ultraviolet light for 3 minutes to obtain the intracranial thrombus aspiration catheter.

Example 2

And 6, coating, namely dissolving 6 parts by weight of glycerol polyacrylate in 40 parts by weight of acetone, stirring at room temperature for 30 minutes, adding 1.8 parts by weight of vinyltrimethoxysilane, continuously stirring for 1 hour, filtering through 0.2 mu m pores to obtain an inner layer solution, adding 15 parts by weight of polyurethane and 3 parts by weight of 1, 4-butanediol diglycidyl ether into 90 parts by weight of acetone, stirring at 50 ℃ for 40 minutes until the mixture is completely dissolved, adding 1.5 parts by weight of pentaerythritol tetraacrylate and 1.5 parts by weight of 2-hydroxy-2-methyl-1-phenylpropione, stirring for 30 minutes, filtering through 0.2 mu m pores to obtain a surface layer solution, uniformly coating the inner layer solution on part of the surface of the catheter, drying in a 60 ℃ oven, coating the surface layer solution on the inner layer, and curing the surface layer solution for 3 minutes by using 310nm ultraviolet light, thus obtaining the intracranial thrombus aspiration catheter.

Example 3

And 6, coating, namely dissolving 6 parts by weight of glycerol polyacrylate in 40 parts by weight of acetone, stirring at room temperature for 30 minutes, adding 1.8 parts by weight of vinyltrimethoxysilane, continuously stirring for 1 hour, filtering through 0.2 mu m pores to obtain an inner layer solution, adding 15 parts by weight of polyurethane and 3 parts by weight of trimethylolpropane triglycidyl ether into 90 parts by weight of acetone, stirring at 50 ℃ for 40 minutes until the mixture is completely dissolved, adding 1.5 parts by weight of trimethylolpropane trimethacrylate and 1.5 parts by weight of 2-hydroxy-2-methyl-1-phenyl acetone, stirring for 30 minutes, filtering through 0.2 mu m pores to obtain a surface layer solution, uniformly coating the inner layer solution on part of the surface of a catheter, drying the catheter in a 60 ℃ oven, coating the inner layer with the surface layer solution on the catheter, curing the catheter with 310nm ultraviolet light for 3 minutes, and obtaining the intracranial thrombus aspiration catheter with the surface layer thickness of 6 mu m.

Example 4

And 6, coating, namely dissolving 6 parts by weight of glycerol polyacrylate in 40 parts by weight of acetone, stirring at room temperature for 30 minutes, adding 1.8 parts by weight of vinyltrimethoxysilane, continuously stirring for 1 hour, filtering through 0.2 mu m pores to obtain an inner layer solution, adding 15 parts by weight of polyethylene glycol and 3 parts by weight of trimethylolpropane triglycidyl ether into 90 parts by weight of acetone, stirring at 50 ℃ for 40 minutes until the polyethylene glycol and 3 parts by weight of trimethylolpropane triglycidyl ether are completely dissolved, adding 1.5 parts by weight of pentaerythritol tetraacrylate and 1.5 parts by weight of 2-hydroxy-2-methyl-1-phenyl acetone, stirring for 30 minutes, filtering through 0.2 mu m pores to obtain a surface layer solution, uniformly coating the inner layer solution on part of the surface of the catheter, drying in a 60 ℃ oven, coating the surface layer solution on the inner layer solution, and curing the inner layer solution for 3 minutes by using 310nm ultraviolet light, wherein the surface layer thickness is 6 mu m, thus obtaining the intracranial thrombus aspiration catheter.

Comparative example 1

And 6, coating, namely dissolving 6 parts by weight of glycerol polyacrylate in 40 parts by weight of acetone, stirring at room temperature for 30 minutes, adding 1.8 parts by weight of vinyltrimethoxysilane, continuously stirring for 1 hour, filtering through 0.2 mu m pores to obtain an inner layer solution, adding 15 parts by weight of polyurethane and 3 parts by weight of 1, 3-propanediol cyclosulfate into 90 parts by weight of acetone, stirring at 50 ℃ for 40 minutes until the mixture is completely dissolved, adding 1.5 parts by weight of pentaerythritol tetraacrylate and 1.5 parts by weight of 2-hydroxy-2-methyl-1-phenylpropione, stirring for 30 minutes, filtering through 0.2 mu m pores to obtain a surface layer solution, uniformly coating the inner layer solution on part of the surface of the catheter, drying in a 60 ℃ oven, coating the surface layer solution on the inner layer, and curing the surface layer solution for 3 minutes by using 310nm ultraviolet light, thus obtaining the intracranial thrombus aspiration catheter.

Comparative example 2

And 6, coating, namely dissolving 6 parts by weight of glycerol polyacrylate in 40 parts by weight of acetone, stirring at room temperature for 30 minutes, adding 1.8 parts by weight of vinyltrimethoxysilane, continuously stirring for 1 hour, filtering through 0.2 mu m pores to obtain an inner layer solution, adding 15 parts by weight of polyurethane and 3 parts by weight of trimethylolpropane triglycidyl ether into 90 parts by weight of acetone, stirring at 50 ℃ for 40 minutes until the mixture is completely dissolved, adding 1.5 parts by weight of glycerol triacrylate and 1.5 parts by weight of 2-hydroxy-2-methyl-1-phenyl acetone, stirring for 30 minutes, filtering through 0.2 mu m pores to obtain a surface layer solution, uniformly coating the inner layer solution on part of the surface of a catheter, drying in a 60 ℃ oven, coating the surface layer solution on the inner layer, curing with 310nm ultraviolet light for 3 minutes, and obtaining the intracranial thrombus aspiration catheter.

Test example 1

Adhesive force performance test:

the adhesive force is tested by a cross-hatch method, and the specific operation is as follows:

Using the intracranial thrombus aspiration catheters prepared in each of the examples and comparative examples, 6X 6 intersecting grids with a pitch of 1mm were engraved on the surface of the coating using a dicing blade. And (3) flatly attaching the 3M adhesive tape to the surface of the scratched grid, and ensuring that the adhesive tape completely covers the grid area. Then, the tape was rapidly peeled off, and the peeling of the coating from the substrate was observed. And grading according to the number of the lattices from which the coating is dropped, wherein the grades are sequentially 0 grade, 1 grade, 2 grade, 3 grade, 4 grade and 5 grade, wherein the grade 0 represents no coating drop, and the grade 5 represents a large amount of coating drop. The test results are shown in Table 1.

TABLE 1

From the data of test example 1, it can be seen that the intracranial thrombus aspiration catheter prepared in example 1 has a good adhesion and a level of shedding of only 0. This may be advantageous in that a combination of polyurethane and trimethylolpropane triglycidyl ether is used in the top solution. Polyurethane has excellent mechanical properties and flexibility, can form stronger adhesive force with a substrate, and trimethylolpropane triglycidyl ether can further enhance the network structure and adhesive force of the coating. In contrast, example 2, although a similar material system was also used, was different in the choice of materials, resulting in slightly poorer adhesion. In comparative examples 1 and 2, 1, 3-propanediol cyclosulfate and glycerol triacrylate were used, respectively, and the adhesion-enhancing effect of these substances was relatively weak, resulting in poor coating adhesion.

Test example 2

Contact angle test:

2. Mu.L of water drops were dropped on the surface of the intracranial thrombus aspiration catheter prepared in each example and comparative example using a microinjector. The side image of the drop was captured using a video optical contact angle tensiometer (LAUDA Scientific company, LSA 100) immediately after the drop contacted the catheter surface. Subsequently, the drop profile is analyzed by means of contact angle measurement software, and the contact angle value is calculated. The magnitude of the contact angle is inversely related to the hydrophilicity of the surface, i.e., the smaller the contact angle, the more hydrophilic the surface. The relevant detection data are shown in Table 2.

TABLE 2

The intracranial thrombus aspiration catheter prepared in example 4 of test example 2 was more hydrophilic and had a contact angle of only 18 °. Probably due to the polyethylene glycol used in its top solution. Polyethylene glycol is a highly hydrophilic polymer, and contains a large number of hydrophilic groups in the molecular chain, and can form hydrogen bonds with water molecules, so that the hydrophilicity of the surface is obviously enhanced. In addition, the molecular structure of the polyethylene glycol is relatively uniform, and a stable hydrophilic coating can be formed. In addition, the trimethylolpropane triglycidyl ether can form a stable network structure, the hydrophilic performance of the coating is further enhanced, the pentaerythritol tetraacrylate molecule contains four acrylate groups, the groups are more in number and uniformly distributed, and more hydrogen bonds can be formed with water molecules, so that the hydrophilic performance is remarkably enhanced. In contrast, trimethylolpropane trimethacrylate and glycerol triacrylate have a smaller number of polar groups and are not distributed uniformly enough, resulting in relatively weak hydrophilicity. The polyurethanes used in the other examples and comparative examples, while having good adhesion, are relatively weak in hydrophilicity. The hydrophilicity of the 1, 3-propanediol cyclosulfate and the glycerol triacrylate used in comparative examples 1 and 2 was poor, resulting in a large contact angle. Thus, example 4 achieves excellent hydrophilic properties by optimizing the material combinations, which is of great significance for the blood compatibility and the operability of intracranial thrombus aspiration catheters in clinical applications.

Claims

1. A method for preparing an intracranial thrombus aspiration catheter, which is characterized by comprising the following steps:

2. The method of claim 1, wherein the intracranial thrombus aspiration catheter is prepared by:

3. The method according to claim 1 or 2, wherein the substrate material in step 6 is at least one of polyurethane and polyethylene glycol.

4. The method according to claim 1 or 2, wherein the glycidyl ether compound in the step 6 is at least one of 1, 4-butanediol diglycidyl ether and trimethylolpropane triglycidyl ether.

5. The method according to claim 1 or 2, wherein the crosslinking agent in step 6 is at least one of trimethylolpropane trimethacrylate and pentaerythritol tetraacrylate.

6. The method according to claim 1 or 2, wherein the photoinitiator in step 6 is at least one of 2-hydroxy-2-methyl-1-phenylpropion and 1-hydroxycyclohexylphenylketone.

7. The method according to claim 1 or 2, wherein the thickness of the inner layer in step 6 is 3-5 μm and the thickness of the outer layer is 5-7 μm.

8. The method according to claim 1 or 2, wherein the uv curing in step 6 is performed by using 300-350nm uv for 2-5 minutes.

9. An intracranial thrombus aspiration catheter prepared by the method of any one of claims 1-8.