Preparation method of hydrophilic lubricating coating on surface of medical interventional catheter

Abstract

The invention discloses a preparation method of a hydrophilic lubricating coating on the surface of a medical interventional catheter, belongs to the technical field of surface modification of medical instruments, and aims to overcome the defects of insufficient lubricating durability, limited coating stability and poor adaptability in the prior art. The preparation method comprises the following steps that a medical intervention catheter base material is sequentially subjected to cleaning and surface activating treatment, a pretreated catheter with active groups on the surface is obtained, the surface of the pretreated catheter is coated with an adhesive force enhancing layer coating, and the bottom layer is formed after curing. The n layers of gradient hydrophilic surface layers are constructed, the content of hydrophilic groups is gradually reduced from the outer layer to the inner layer, the degree of crosslinking is gradually improved, progressive water absorption is achieved, compared with an existing single-layer surface layer structure, the effective lubrication time is prolonged by 2-3 times, and the whole medium and long-term interventional operation can be stably covered.

Description

A method for preparing a hydrophilic lubricating coating on the surface of a medical interventional catheter Technical Field

[0001] This invention relates to the field of medical device surface modification technology, and more particularly to a method for preparing a hydrophilic lubricating coating on the surface of a medical interventional catheter. Background Technology

[0002] Interventional catheters are core devices in interventional diagnostic and treatment procedures, and their surface lubrication performance directly affects the smoothness of the procedure and patient safety. To reduce the coefficient of friction between the catheter and the blood vessel wall during intervention, and to minimize the risks of vascular injury, spasm, and thrombosis, a hydrophilic lubricating coating is typically prepared on the catheter surface. Current technologies often employ a composite structure of a "bottom layer + single-layer top layer." The bottom layer serves as an adhesion-enhancing layer, improving the adhesion between the coating and the catheter substrate and preventing the coating from detaching under immersion in body fluids and friction. The top layer is a hydrophilic functional layer, usually made of hydrophilic materials such as polyvinylpyrrolidone (PVP) or methacryloyloxyethylphosphorylcholine (MPC). Before use, it is activated by soaking in sterile water or saline solution, absorbing moisture to form a hydrogel layer for lubrication. This preparation method is relatively simple and low-cost, and has been widely used in the production of disposable hydrophilic coated guidewires, angiography catheters, and other interventional devices.

[0003] However, existing methods for preparing a base layer plus a single-layer surface layer have significant drawbacks: First, after the hydrophilic material of the single-layer surface layer absorbs water to form a hydrogel, the water is easily lost rapidly under the continuous friction and flushing action of body fluids during the operation, causing the lubrication performance to decrease sharply as the operation time increases. This makes it difficult to meet the needs of complex coronary interventions, neurointerventions, and other medium- to long-term procedures (lasting more than 30 minutes), resulting in insufficient lubrication durability. Second, to ensure the initial water absorption and activation speed, the single-layer surface layer usually adopts a low cross-linking design. When immersed in body fluids for a long time, it is prone to swelling or even detachment, producing polymer particles. This poses a potential risk of particle embolism, seriously threatening patient safety, and limiting the stability of the coating. In addition, the duration of different interventional procedures varies greatly, and existing methods cannot flexibly adjust the coating structure according to the operation time. If the surface layer thickness is simply increased or the hydrophilic material content is increased to adapt to medium- to long-term procedures, the initial water absorption and activation speed will be slowed down, affecting the maneuverability in the initial stage of the operation and resulting in poor adaptability. Summary of the Invention

[0004] To overcome the above problems, this invention aims to propose a method for preparing a hydrophilic lubricating coating on the surface of a medical interventional catheter. This method addresses the shortcomings of existing technologies, such as insufficient lubrication durability, limited coating stability, and poor adaptability. This invention provides a method for preparing a hydrophilic lubricating coating on the surface of a medical interventional catheter. By constructing a gradient hydrophilic surface structure, it achieves gradual water absorption, prolongs the effective lubrication time, improves coating stability, and adapts to the needs of interventional surgeries of different durations.

[0005] Therefore, the specific technical solution adopted by the present invention is as follows: According to one aspect of the present invention, a method for preparing a hydrophilic lubricating coating on the surface of a medical interventional catheter is provided, comprising the following steps: S1, sequentially cleaning and surface-activating the medical interventional catheter substrate to obtain a pretreated catheter with active groups on the surface; S2, coating the surface of the pretreated catheter with an adhesion-enhancing layer coating, which is cured to form a bottom layer; S3, sequentially coating the bottom layer with n layers of hydrophilic surface coating and curing each layer to form a gradient hydrophilic surface layer; wherein the content of hydrophilic groups in the n hydrophilic surface layers gradually decreases and the degree of crosslinking gradually increases from the outer layer to the inner layer; wherein n is a positive integer calculated based on the operation time, and the calculation formula is: n=ceil(T / 30), where: n is the number of hydrophilic surface layers, ceil is the rounding function, T is the designed continuous use time of the medical interventional catheter (unit: min), and n≥2; S4, cleaning and drying the coated catheter to obtain a medical interventional catheter with a hydrophilic lubricating coating on the surface.

[0006] Optionally, in S1, the cleaning involves immersing the conduit substrate in a mixture of anhydrous ethanol and deionized water for ultrasonic cleaning for 8-12 minutes, wherein the volume ratio of anhydrous ethanol to deionized water in the mixture is 1:1, and then drying it with nitrogen gas.

[0007] Optionally, in S1, the surface activation treatment is oxygen plasma treatment, with the following parameters: power 70-90W, pressure 450-550mTorr, treatment time 10-15min, and the contact angle of the conduit surface after treatment ≤40°.

[0008] Optionally, in S2, the adhesion-enhancing coating is composed of the following raw materials in parts by weight: 100 parts of waterborne polyurethane dispersion, 2-3 parts of silane coupling agent, 1-2 parts of aziridine crosslinking agent, and 20-30 parts of deionized water.

[0009] Optionally, in S2, the coating is performed by dip coating, with a dip coating speed of 90-110 mm / min and a pull-up speed of 45-55 mm / min; the curing conditions are constant temperature baking at 80℃ for 25-35 min, and the thickness of the base layer after curing is 5-8 μm.

[0010] Optionally, in S3, the raw materials of the hydrophilic surface coating include hydrophilic monomers, crosslinking agents, plasticizers, and deionized water; in the n layers of hydrophilic surface coating from the outer layer to the inner layer, the mass fraction of hydrophilic monomers gradually decreases by 3-5%, and the mass fraction of crosslinking agents gradually increases by 0.2-0.4%.

[0011] Optionally, the hydrophilic monomer is a mixture of polyvinylpyrrolidone and methacryloyloxyethyl phosphorylcholine; in the outer hydrophilic surface coating, polyvinylpyrrolidone is selected from type K30 with a mass fraction of 18-22%, and methacryloyloxyethyl phosphorylcholine has a mass fraction of 6-10%; in the inner hydrophilic surface coating, polyvinylpyrrolidone is selected from type K90 with a mass fraction of 10-14%, and methacryloyloxyethyl phosphorylcholine has a mass fraction of 2-4%.

[0012] Optionally, the crosslinking agent is a 25% glutaraldehyde aqueous solution, the mass fraction of the crosslinking agent in the outer hydrophilic surface coating is 0.2-0.4%, and the mass fraction of the crosslinking agent in the inner hydrophilic surface coating is 0.8-1.2%; the plasticizer is glycerol, and the mass fraction of glycerol in each hydrophilic surface coating is 1-2%.

[0013] Optionally, in S3, the coating is carried out by dip coating, and the dip coating speed is gradually reduced by 5-10 mm / min from the outer layer to the inner layer, and the viscosity of each layer of hydrophilic surface coating is gradually increased by 30-50 mPa·s; the curing conditions are constant temperature baking at 55-65℃ for 30-40 min, and the thickness of each hydrophilic surface layer after layer-by-layer curing is 8-15 μm.

[0014] Optionally, the substrate of the medical interventional catheter is polyurethane, polyether block amide, or polyvinyl chloride.

[0015] Compared to existing technologies, this application has the following advantages: This invention constructs an n-layer gradient hydrophilic surface layer, with the content of hydrophilic groups gradually decreasing and the degree of cross-linking gradually increasing from the outer layer to the inner layer, achieving gradual water absorption. During pre-soaking, the outer highly hydrophilic coating rapidly absorbs water and activates to form an initial hydrogel lubricating layer; during surgery, when the lubricity of the outer layer decreases, the inner coating slowly hydrates through water permeated from the outer layer or by directly absorbing body fluids, continuously replenishing the lubrication effect. Compared to existing single-layer surface structures, the effective lubrication time is extended by 2-3 times, stably covering the entire process of medium- and long-term interventional surgeries.

[0016] The inner hydrophilic surface layer adopts a high degree of cross-linking design, which enhances the bonding force with the underlying layer and prevents swelling and peeling under long-term immersion in body fluids. At the same time, the layer-by-layer curing process ensures tight interlayer bonding, reduces the risk of coating peeling and the generation of microparticles, reduces safety hazards in clinical applications, and meets the regulatory requirements for the integrity of medical device coatings.

[0017] This invention uses the formula n=ceil(T / 30) to accurately calculate the number of hydrophilic surface layers. The number of layers can be flexibly adjusted according to the expected duration of different interventional surgeries. For example, two surface layers are used for short surgeries (T≤30min), three surface layers are used for medium- to long-term surgeries (30min<T≤60min), and four or more surface layers are used for special long-term surgeries (T>60min). This avoids waste of resources and improves the versatility of the solution.

[0018] This invention is based on an improvement of the traditional dip coating process. It does not require the addition of complex equipment, and existing production lines can be directly debugged and adapted. The coating parameters are easy to control, which is conducive to large-scale production and reduces production costs. Attached Figure Description

[0019] The above-mentioned features, characteristics, and advantages of the present invention, as well as their implementation methods, will become clearer and more readily understood in conjunction with the following description of the embodiments, which are illustrated in detail with reference to the accompanying drawings. Hereinafter, a schematic diagram is provided: Figure 1 is a flowchart of a method for preparing a hydrophilic lubricating coating on the surface of a medical interventional catheter according to an embodiment of the present invention. Detailed Implementation

[0020] To enable those skilled in the art to better understand the present application, the technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present application, and not all embodiments. Based on the embodiments in the present application, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of the present application.

[0021] Example 1: Adaptation to short-term interventional surgery (T=25min, n=ceil(25 / 30)=2) Based on extensive clinical data statistics and simulated surgical friction tests, the traditional hydrophilic lubricating coating with a "bottom layer + single-layer surface layer" structure has an effective lubrication time limit of 30min under test conditions simulating human body fluid environment, 1N load, and 50mm / min friction speed. After 30min, the coating friction coefficient exceeds 0.08, which cannot meet the lubrication requirements of interventional surgery. Therefore, this invention uses 30min as the benchmark value for the effective lubrication time of a single-layer gradient surface layer, and determines the number of gradient surface layers by using the rounding function ceil(T / 30) to ensure that the effective lubrication time of the coating covers the entire surgical procedure.

[0022] This embodiment prepares a hydrophilic lubricating coating for a medical interventional catheter suitable for a short 25-minute interventional procedure. The catheter substrate is polyurethane (PUR). The specific steps are as follows: S1, Immerse the PUR catheter in a 1:1 volume ratio mixture of anhydrous ethanol and deionized water, ultrasonically clean for 10 minutes, remove and dry with nitrogen; then perform oxygen plasma treatment with the following parameters: power 80W, pressure 500mTorr, treatment time 12 minutes. After treatment, the contact angle of the catheter surface is 38°; S2, Prepare an adhesion-enhancing coating. The raw material mass fraction is: waterborne polyurethane dispersion ( Mix 100 parts of a 30% solids content silane coupling agent, 2.5 parts of KH-570 silane coupling agent, 1.5 parts of XR-100 aziridine crosslinking agent, and 25 parts of deionized water. Stir for 30 minutes until homogeneous, and adjust the viscosity to 180 mPa·s. Apply the mixture to the surface of the pretreated conduit using a dip-coating method at a speed of 100 mm / min and a pulling speed of 50 mm / min. Then bake in an 80℃ oven for 30 minutes and cool to room temperature to form a 6 μm thick underlayer. S3, Gradient Surface Coating and Curing: S31, Inner Hydrophilic Surface Coating and Curing: Prepare the inner hydrophilic surface layer. The coating, with the following raw material weight parts: PVPK90 12 parts, MPC 3 parts, 25% glutaraldehyde aqueous solution 1.0 part, glycerin 1 part, deionized water 83 parts, stirred for 30 min until completely dissolved, and the viscosity adjusted to 200 mPa·s; applied to the base surface using the dip coating method, with a lifting speed of 40 mm / min; then baked in a 60℃ oven for 40 min, cooled to room temperature, forming an inner hydrophilic surface layer with a thickness of 9 μm; S32, outer hydrophilic surface layer coating and curing: Prepare the outer hydrophilic surface layer coating, with the following raw material weight parts: PVPK30 20 parts, MPC 8 parts, 0.3 parts of 25% glutaraldehyde aqueous solution, 1 part of glycerol, and 70.7 parts of deionized water were stirred for 20 min until completely dissolved, and the viscosity was adjusted to 120 mPa·s. The inner hydrophilic surface layer was coated by dip coating at a lifting speed of 50 mm / min. The coating was then baked in an oven at 55℃ for 30 min and cooled to room temperature to form an outer hydrophilic surface layer with a thickness of 13 μm. S4. The coated catheter was immersed in deionized water and ultrasonically cleaned for 5 min to remove free monomers from the surface. It was then vacuum dried at 40℃ for 2 h to obtain a PUR interventional catheter with a hydrophilic lubricating coating on the surface.

[0023] The catheter prepared in this embodiment was subjected to performance testing: the initial water contact angle was 24°, and the initial coefficient of friction (COF) was 0.028; in the simulated surgical friction test, when the friction duration reached 65 min, the coefficient of friction increased to 0.081, and the effective lubrication duration was 65 min, which is 2.17 times longer than that of the comparative example. The cross-cut test (ASTM D3359) was grade 0, with no coating peeling; after immersion in physiological saline at 37°C for 7 days, the coefficient of friction changed by 18%, the cytotoxicity was grade 1, and the hemolysis rate was 2.3%.

[0024] Example 2: Adaptation to Medium- to Long-Term Interventional Surgery (T=70min, n=ceil(70 / 30)=3) This example describes the preparation of a hydrophilic lubricating coating for a medical interventional catheter adapted to a 70-minute medium- to long-term interventional surgery. The catheter substrate is polyether block amide (PEBAX). The specific steps are as follows: S1. Immerse the PEBAX catheter in a 1:1 volume ratio mixture of anhydrous ethanol and deionized water, ultrasonically clean for 12 minutes, remove and dry with nitrogen; subsequently, perform oxygen plasma treatment with the following parameters: power 90W, pressure 550mTorr, treatment time 15min. After treatment, the contact angle of the catheter surface is 35°. °; S2. Prepare the adhesion-enhancing coating. The raw materials are: 100 parts by weight of waterborne polyurethane dispersion (30% solid content), 3 parts of KH-570 silane coupling agent, 2 parts of XR-100 aziridine crosslinking agent, and 30 parts of deionized water. Stir for 30 minutes until uniform and adjust the viscosity to 200 mPa·s. Apply the coating to the surface of the pretreated conduit using the dip-coating method at a dip-coating speed of 110 mm / min and a pull-up speed of 55 mm / min. Then bake at a constant temperature of 80°C for 35 minutes and cool to room temperature to form a base layer with a thickness of 8 μm; S3. Gradient surface coating and curing: S31. Inner hydrophilic surface layer Coating and Curing: Prepare the inner hydrophilic surface coating with the following raw material parts by weight: 14 parts PVPK90, 4 parts MPC, 1.2 parts 25% glutaraldehyde aqueous solution, 2 parts glycerol, and 78.8 parts deionized water. Stir for 30 minutes until completely dissolved, and adjust the viscosity to 220 mPa·s. Apply the coating to the bottom layer surface using the dip-coating method at a lifting speed of 40 mm / min. Then bake in a 65℃ oven for 40 minutes, cool to room temperature, and form an inner hydrophilic surface layer with a thickness of 10 μm. S32, Intermediate Hydrophilic Surface Coating and Curing: Prepare the intermediate hydrophilic surface coating with the following raw material parts by weight: 15 parts PVPK60, 1.2 parts MPC, 1.2 parts 25% glutaraldehyde aqueous solution, 2 parts glycerol, and 78.8 parts deionized water. C5 parts, 25% glutaraldehyde aqueous solution 0.6 parts, glycerin 1.5 parts, deionized water 77.9 parts, stir for 25 min until completely dissolved, adjust the viscosity to 180 mPa·s; apply to the inner hydrophilic surface layer using the dip-coating method, with a lifting speed of 45 mm / min; then bake in a 60℃ oven for 35 min, cool to room temperature, forming a 12 μm thick intermediate hydrophilic surface layer; S33, outer hydrophilic surface layer coating and curing: prepare the outer hydrophilic surface layer coating, the raw material mass parts are: PVPK30 22 parts, MPC 10 parts, 25% glutaraldehyde aqueous solution 0.4 parts, glycerin 2 parts, deionized water 65.Six parts were mixed and stirred for 20 minutes until completely dissolved, adjusting the viscosity to 150 mPa·s. The mixture was then dip-coated onto the surface of the intermediate hydrophilic surface layer at a pulling speed of 55 mm / min. Subsequently, it was baked in a 55℃ oven for 30 minutes and cooled to room temperature to form a 15 μm thick outer hydrophilic surface layer. S4. The coated catheter was immersed in deionized water and ultrasonically cleaned for 6 minutes to remove free monomers from the surface. It was then vacuum dried at 60℃ for 4 hours to obtain a PEBAX interventional catheter with a hydrophilic lubricating coating.

[0025] The catheter prepared in this embodiment was subjected to performance testing: the initial water contact angle was 22°, and the initial coefficient of friction (COF) was 0.025; in the simulated surgical friction test, when the friction time reached 88 min, the coefficient of friction increased to 0.080, and the effective lubrication time was 88 min, which is 2.93 times longer than that of the comparative example. The cross-cut test (ASTM D3359) was grade 0, with no coating peeling; after immersion in physiological saline at 37°C for 7 days, the coefficient of friction changed by 22%, the cytotoxicity was grade 1, and the hemolysis rate was 1.8%.

[0026] Comparative Example (Traditional Substrate + Single-Layer Surface Structure): A hydrophilic lubricating coating for a medical interventional catheter with a "substrate + single-layer surface" structure was prepared. The catheter substrate was polyurethane (PUR). The specific steps were as follows: Catheter substrate pretreatment: exactly the same as step 1) of Example 1, after which the contact angle of the catheter surface was 38°; Substrate coating and curing: exactly the same as step 2) of Example 1, forming a substrate with a thickness of 6μm; Single-layer surface coating and curing: a single-layer hydrophilic surface coating was prepared, with the following raw material mass parts: 20 parts PVPK30, 8 parts MPC, 0.3 parts 25% glutaraldehyde aqueous solution, 1 part glycerol, and 70.7 parts deionized water. The mixture was stirred for 20 min until completely dissolved, and the viscosity was adjusted to 120 mPa·s; the coating was applied to the substrate surface using a dip-coating method at a lifting speed of 50 mm / min; then baked in a 55°C oven for 30 min, and cooled to room temperature to form a single-layer surface with a thickness of 22μm (the total thickness was the same as the total thickness of the double-layer surface in Example 1); Post-treatment: exactly the same as step 4) of Example 1.

[0027] The performance of the catheter prepared in this comparative example was tested: the initial water contact angle was 25° and the initial coefficient of friction (COF) was 0.030; in the simulated surgical friction test, when the friction time reached 30 min, the coefficient of friction increased to 0.082 (beyond 0.08, it loses its effective lubrication effect), and the effective lubrication time was 30 min.

[0028] Although the present invention has been disclosed above with reference to preferred embodiments, the embodiments are merely examples for illustrative purposes and are not intended to limit the present invention. Those skilled in the art can make various modifications and refinements without departing from the spirit and scope of the present invention. The scope of protection claimed by the present invention should be determined by the claims.

Claims

1. A method for preparing a hydrophilic lubricating coating on the surface of a medical interventional catheter, characterized in that, Includes the following steps: S1. The medical interventional catheter substrate is sequentially cleaned and surface activated to obtain a pretreated catheter with active groups on the surface. S2. Apply an adhesion-enhancing coating to the surface of the pretreated catheter, and cure it to form the bottom layer; S3. Apply n layers of hydrophilic surface coating to the bottom layer and cure them layer by layer to form a gradient hydrophilic surface layer; the content of hydrophilic groups in the n hydrophilic surface layers gradually decreases and the degree of crosslinking gradually increases from the outer layer to the inner layer; where n is a positive integer calculated based on the operation time, and the calculation formula is: n=ceil(T / 30), where: n is the number of hydrophilic surface layers, ceil is the rounding function, T is the design continuous use time of the medical interventional catheter (unit: min), and n≥2; S4. Clean and dry the coated catheter to obtain a medical interventional catheter with a hydrophilic lubricating coating on the surface.

2. The method for preparing a hydrophilic lubricating coating on the surface of a medical interventional catheter according to claim 1, characterized in that, In S1, the cleaning process involves immersing the conduit substrate in a mixture of anhydrous ethanol and deionized water and ultrasonically cleaning it for 8-12 minutes. The volume ratio of anhydrous ethanol to deionized water in the mixture is 1:

1. After cleaning, the substrate is dried with nitrogen gas.

3. The method for preparing a hydrophilic lubricating coating on the surface of a medical interventional catheter according to claim 1, characterized in that, In S1, the surface activation treatment is oxygen plasma treatment, with the following parameters: power 70-90W, pressure 450-550mTorr, treatment time 10-15min, and the contact angle of the conduit surface after treatment ≤40°.

4. The method for preparing a hydrophilic lubricating coating on the surface of a medical interventional catheter according to claim 1, characterized in that, In S2, the adhesion-enhancing coating is composed of the following raw materials in parts by weight: 100 parts of waterborne polyurethane dispersion, 2-3 parts of silane coupling agent, 1-2 parts of aziridine crosslinking agent, and 20-30 parts of deionized water.

5. The method for preparing a hydrophilic lubricating coating on the surface of a medical interventional catheter according to claim 1, characterized in that, In S2, the coating is applied by dip coating, with a dip coating speed of 90-110 mm / min and a pull-up speed of 45-55 mm / min; the curing conditions are constant temperature baking at 80℃ for 25-35 min, and the thickness of the base layer after curing is 5-8 μm.

6. The method for preparing a hydrophilic lubricating coating on the surface of a medical interventional catheter according to claim 1, characterized in that, In S3, the raw materials of the hydrophilic surface coating include hydrophilic monomers, crosslinking agents, plasticizers, and deionized water; in the n layers of hydrophilic surface coating from the outer layer to the inner layer, the mass fraction of hydrophilic monomers gradually decreases by 3-5%, and the mass fraction of crosslinking agents gradually increases by 0.2-0.4%.

7. The method for preparing a hydrophilic lubricating coating on the surface of a medical interventional catheter according to claim 6, characterized in that, The hydrophilic monomer is a mixture of polyvinylpyrrolidone and methacryloyloxyethyl phosphorylcholine; in the outer hydrophilic surface coating, polyvinylpyrrolidone of type K30 is selected with a mass fraction of 18-22%, and methacryloyloxyethyl phosphorylcholine has a mass fraction of 6-10%; in the inner hydrophilic surface coating, polyvinylpyrrolidone of type K90 is selected with a mass fraction of 10-14%, and methacryloyloxyethyl phosphorylcholine has a mass fraction of 2-4%.

8. The method for preparing a hydrophilic lubricating coating on the surface of a medical interventional catheter according to claim 6, characterized in that, The crosslinking agent is a 25% glutaraldehyde aqueous solution, with a crosslinking agent mass fraction of 0.2-0.4% in the outer hydrophilic surface coating and 0.8-1.2% in the inner hydrophilic surface coating; the plasticizer is glycerol, with a glycerol mass fraction of 1-2% in each hydrophilic surface coating.

9. The method for preparing a hydrophilic lubricating coating on the surface of a medical interventional catheter according to claim 1, characterized in that, In S3, the coating is carried out by dip coating. From the outer layer to the inner layer, the dip coating speed is gradually reduced by 5-10 mm / min, and the viscosity of each layer of hydrophilic surface coating is gradually increased by 30-50 mPa·s. The curing conditions are constant temperature baking at 55-65℃ for 30-40 min. After layer-by-layer curing, the thickness of each hydrophilic surface layer is 8-15 μm.

10. The method for preparing a hydrophilic lubricating coating on the surface of a medical interventional catheter according to claim 1, characterized in that, The substrate of the medical interventional catheter is polyurethane, polyether block amide, or polyvinyl chloride.

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