Preparation method of balloon catheter protective sleeve

Abstract

The invention relates to a preparation method of a balloon catheter protective sleeve, the preparation method comprises the steps of carrying out sectioning folding treatment on a balloon, and then forming the protective sleeve on the balloon by using a protective sleeve forming device, and the preparation method comprises the following steps: a, immersing the folded balloon in a degradable polymer solution; b, removing the redundant degradable polymer solution on the surface of the balloon; and c, curing the degradable polymer solution on the surface of the balloon to form the protective sleeve in situ. The degradable protective sleeve is formed on the outer side of the balloon of the balloon catheter in situ, the balloon can be effectively prevented from loosening and expanding after being folded and wound to affect use, and the protective sleeve can be naturally dissolved in a blood vessel in the operation process, does not need to be manually removed and is better in safety.

Description

Technical Field

[0001] The present invention belongs to the technical field of medical devices, and particularly relates to a preparation method for a protective sleeve of a balloon catheter. Background Art

[0002] Existing balloon dilation catheters usually use protective sleeves to cover the balloon. After the balloon is folded by a balloon folding machine, the protective sleeve is then put on to prevent the balloon from loosening and expanding after being folded and wound, which affects its use. However, this kind of protective sleeve needs to be manually removed by medical staff during the operation, increasing the difficulty of operation, and it is easy to occur that the protective sleeve is too tight for the doctor to remove or the intern doctor directly inserts into the human body without removing the protective sleeve, which is not convenient and has certain safety risks. Summary of the Invention

[0003] The purpose of the present invention is to provide a preparation method for a protective sleeve of a balloon catheter, by forming a degradable protective sleeve in situ on the outside of the balloon, which can be naturally dissolved in the blood vessel without manual removal.

[0004] To achieve the above purpose, the technical solution adopted by the present invention is:

[0005] The present invention provides a preparation method for a protective sleeve of a balloon catheter. The balloon catheter includes a catheter and a balloon disposed on the catheter and capable of expanding or contracting. The preparation method includes performing a lobed folding process on the balloon, and then using a protective sleeve forming device to form the protective sleeve on the balloon. The protective sleeve forming device includes a container, a restricting member movably disposed in the container and having a relaxed state and a tightened state, a driving mechanism connected to the restricting member and used to drive the restricting member to switch between the relaxed state and the tightened state, a curing mechanism disposed in the container, and a liquid material mechanism connected to the container and used to introduce or discharge a raw material liquid into or out of the container.

[0006] Using the protective sleeve forming device to form the protective sleeve on the balloon includes the following steps:

[0007] a. Introduce the raw material liquid into the container through the liquid material mechanism, then insert the folded balloon into the restricting member in the relaxed state and immerse it in the raw material liquid, and perform a vacuum treatment on the balloon catheter to make the inside of the balloon catheter in a vacuum environment or a low-pressure environment. The raw material liquid is a degradable polymer solution;

[0008] b. The driving mechanism drives the restricting member to switch from the relaxed state to the tightened state, removing the excess degradable polymer solution on the surface of the balloon;

[0009] c. Drain the degradable polymer solution in the container through the liquid feeding mechanism, and start the curing mechanism to cure the degradable polymer solution on the surface of the balloon, and in-situ form the protective sleeve.

[0010] Preferably, the limiting member is a net-shaped annular structure. When the limiting member switches from the relaxed state to the tightened state, the inner diameter of at least part of the limiting member shrinks and can squeeze the balloon.

[0011] Preferably, the upper and lower ends of the limiting member are open.

[0012] Preferably, when the limiting member is in the tightened state, the middle diameter of the limiting member is small and the upper and lower ends have large diameters.

[0013] In some embodiments, when the limiting member is in the tightened state, the limiting member is in an hourglass shape.

[0014] Preferably, the driving mechanism is connected to at least one of the upper and lower ends of the limiting member and can drive this end to move away from the other end to switch the limiting member to the tightened state; or move towards the other end to switch the limiting member to the relaxed state.

[0015] Further preferably, the driving mechanism includes a slide rail extending along the height direction of the container, two connecting members respectively arranged at the upper and lower ends of the slide rail, and a driving member. The upper end and the lower end of the limiting member are respectively connected to the two connecting members, and at least one of the two connecting members is connected to the driving member and can slide along the extending direction of the slide rail under the drive of the driving member. The driving mechanism has two groups symmetrically arranged outside the limiting member.

[0016] In some embodiments, one of the two connecting members is fixed and the other slides on the slide rail. Further, the connecting member located above slides.

[0017] In some embodiments, both of the two connecting members slide on the slide rail, and the driving member has two groups corresponding to the two connecting members.

[0018] Preferably, the preparation method further includes pressurizing the container after step a and before step b to control the pressure in the container to be 0.11 - 0.2 Mpa and maintaining it for 1 - 3 minutes.

[0019] Preferably, step a includes immersing the limiting member in the degradable polymer solution for 20 - 60 s, and then performing a vacuum pumping treatment on the balloon catheter.

[0020] Preferably, the curing mechanism includes a plurality of ultraviolet irradiation lamps arranged along the inner circumference of the container inside the container.

[0021] Preferably, the preparation method further includes, after step c, a step of driving the limiting member by the driving mechanism to switch from a tightened state to a relaxed state, and then taking out the balloon catheter.

[0022] Preferably, based on the total mass of the degradable polymer solution being 100%, the degradable polymer solution includes:

[0023] 5-10% of polyethylene glycol diacrylate,

[0024] 0.1-2.5% of a photoinitiator,

[0025] 0.5-1% of a dissolution promoter,

[0026] The balance is solvent.

[0027] In some embodiments, the number average molecular weight of the polyethylene glycol diacrylate is 700-1000.

[0028] In some embodiments, the photoinitiator is 2-hydroxy-2-methyl-1-phenyl-1-propanone.

[0029] In some embodiments, the dissolution promoter is lactic acid and / or lactide.

[0030] In some embodiments, the solvent is water.

[0031] In some embodiments, the degradable polymer solution further includes phosphate buffered saline (PBS) to make the pH of the degradable polymer solution 7.35-7.45.

[0032] Due to the application of the above technical solutions, the present invention has the following advantages compared with the prior art:

[0033] By in-situ forming a degradable protective sleeve outside the balloon of the balloon catheter, the present invention can effectively prevent the balloon from loosening and expanding after being folded and wound, which affects the use. The protective sleeve can be naturally dissolved in the blood vessel during the operation without manual removal, and the safety is better. Description of the Drawings

[0034] In order to more clearly illustrate the technical solutions of the embodiments of the present application, the drawings required for the description of the embodiments will be briefly introduced below. Obviously, the drawings in the following description are only some embodiments of the present application. For those of ordinary skill in the art, other drawings can be obtained based on these drawings without creative efforts.

[0035] Figure 1Perspective view of the sheath forming device provided for Example 1, wherein the restricting member is in a relaxed state;

[0036] Figure 2 For Figure 1 Schematic cross-sectional structure diagram;

[0037] Figure 3 Perspective view of the sheath forming device provided for Example 1, wherein the restricting member is in a tightened state;

[0038] Figure 4 Schematic structure diagram of the restricting member in a tightened state provided for Example 1;

[0039] Figure 5 Schematic cross-sectional view of the sheath formed on the balloon provided for Example 1;

[0040] Figure 6 Physical effect diagram of the sheath formed on the balloon provided for Example 1;

[0041] Wherein: 1. Balloon; 11. Valve leaflet; 2. Catheter; 3. Container; 31. Pressure gauge; 32. Raw material liquid pipeline; 4. Restricting member; 41. Stainless steel wire; 5. Slide rail; 6. Connecting member; 7. Ultraviolet irradiation lamp; 8. Sheath layer. Detailed implementation manners

[0042] In the following, only some exemplary embodiments are simply described. As those skilled in the art can recognize, the described embodiments can be modified in various different ways without departing from the spirit or scope of the embodiments of the present invention. Therefore, the drawings and the description are considered to be exemplary in nature rather than restrictive.

[0043] In the description of the embodiments of the present invention, it should be understood that the distal end refers to the end of the instrument or component away from the operator, and the proximal end refers to the end of the instrument or component close to the operator; the axial direction refers to the direction parallel to the center line connecting the distal end and the proximal end of the instrument or component; the inner and outer are positions defined by the distance relative to the center of the instrument or component, wherein the inner is the position close to the center of the instrument or component, and the outer is the position away from the center of the instrument or component; the up and down refer to the orientation of the instrument in the actual use or working state. The description of the above orientation words is only for the convenience of describing the embodiments of the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation to the embodiments of the present invention.

[0044] In addition, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the quantity of the indicated technical features. Thus, features defined with "first" and "second" may explicitly or implicitly include one or more of such features. In the description of the embodiments of the present invention, "a plurality of" means two or more unless otherwise specifically defined.

[0045] In the embodiments of the present invention, unless otherwise clearly specified and limited, the first feature being "on" or "under" the second feature may include the first and second features being in direct contact, or may include the first and second features not being in direct contact but being in contact through additional features therebetween. Moreover, the first feature being "above", "over" and "on top of" the second feature includes the first feature being directly above and obliquely above the second feature, or merely indicating that the first feature has a higher horizontal height than the second feature. The first feature being "under", "below" and "beneath" the second feature includes the first feature being directly below and obliquely below the second feature, or merely indicating that the first feature has a lower horizontal height than the second feature.

[0046] The following disclosure provides many different embodiments or examples for implementing different structures of the embodiments of the present invention. To simplify the disclosure of the embodiments of the present invention, the components and settings of specific examples are described below. Of course, they are merely examples and are not intended to limit the embodiments of the present invention. In addition, the embodiments of the present invention may repeat reference numerals and / or reference letters in different examples. Such repetition is for the purpose of simplification and clarity and does not itself indicate the relationship between the various embodiments and / or settings discussed.

[0047] The embodiments of the present invention will be described in detail below with reference to the accompanying drawings.

[0048] Embodiment 1

[0049] The present invention provides a protective cover forming device, as Figures 1 to 3 shown, which includes a container 3, a restricting member 4 movably disposed in the container 3 and having a relaxed state and a tightened state, a driving mechanism connected to the restricting member 4 and used to drive the restricting member 4 to switch between the relaxed state and the tightened state, a curing mechanism disposed on the container 3, and a liquid material mechanism (not shown in the figure) connected to the container 3 and used to introduce or discharge the raw material liquid into or out of the container 3.

[0050] As Figures 1 to 4As shown, the restricting member 4 is a net-shaped annular structure, which can specifically be woven from stainless steel wires 41. The restricting member 4 is arranged in the middle area of the container 3, and at least one of its upper and lower ends has an opening to facilitate the entry of the balloon 1. In this embodiment, both the upper and lower ends of the restricting member 4 have openings. When the restricting member 4 switches from the relaxed state to the tightened state, the inner diameter of at least part of the restricting member 4 decreases. Preferably, when the restricting member 4 is in the tightened state, the inner diameter of the restricting member 4 in the middle decreases, so that it presents an hourglass shape with a small middle diameter and large upper and lower end diameters.

[0051] The driving mechanism is connected to at least one of the upper and lower ends of the restricting member 4, and can drive this end to move away from the other end, so that the restricting member 4 switches to the tightened state; or move towards the other end, so that the restricting member 4 switches to the relaxed state.

[0052] In this embodiment, there are two groups of driving mechanisms symmetrically arranged outside the restricting member 4. Taking one of the groups as an example, the driving mechanism includes a slide rail 5 extending along the height direction of the container 3, two connecting members 6 respectively arranged at the upper and lower ends of the slide rail 5, and a driving member (not shown in the figure). The upper and lower ends of the restricting member 4 are respectively connected to the two connecting members 6. The driving member can be a set only connected to one of the connecting members 6, or two sets respectively connected to the two connecting members 6. Preferably, the driving member has a set connected to the upper connecting member 6 to drive the upper connecting member 6 to slide along the extending direction of the slide rail 5. The driving member can be a telescopic motor, and the telescopic rod of the telescopic motor is connected to the connecting member 6 and the telescopic direction is the same as the extending direction of the slide rail 5. In some other embodiments, the driving member can also include a belt arranged in the slide rail 5, a gear meshing with the belt, and a motor for driving the gear to rotate to drive the belt to move. The connecting member 6 is connected to the belt and slides on the slide rail 5 driven by the belt.

[0053] The curing mechanism includes a plurality of ultraviolet irradiation lamps 7 uniformly arranged in the container 3 along the inner circumference of the container 3.

[0054] The container 3 is preferably a pressure vessel 3 that can be pressurized. Its bottom end is connected to a raw material liquid pipeline 32 and its top end has a feed port for the balloon catheter to enter. The raw material liquid pipeline 32 is communicated with the liquid supply mechanism, and the feed port is located in the middle position. A pressure gauge 31 is also connected to the container 3.

[0055] The present invention also provides a preparation method for a balloon catheter protective sleeve. The balloon catheter includes a catheter and a balloon provided on the catheter that can expand or contract. The specific structure can refer to the prior art and the present invention does not make limitations. The preparation method includes the following steps:

[0056] S1. Surface treatment of the balloon 1:

[0057] S1.1. Selectively use a fine grinding device or chemical treatment (such as a low-concentration acidic solution) to slightly increase the surface roughness of the balloon 1, thereby increasing the bonding force between the surface of the balloon 1 and the degradable polymer solution and avoiding uneven attachment of the degradable polymer coating;

[0058] S1.2. Use non-woven fabric and a special cleaning solvent to clean the surface of the balloon 1 to ensure that there is no dust, grease, or impurities on the surface of the balloon 1.

[0059] S2. Preparation of the degradable polymer solution:

[0060] Based on the total mass of the degradable polymer solution being 100%, the degradable polymer solution includes:

[0061] Polyethylene glycol diacrylate (PEGDA) with a number average molecular weight of 700 - 1000: 7.5%;

[0062] 2-Hydroxy-2-methyl-1-phenyl-1-propanone (HMPP): 2%;

[0063] Lactic acid or lactide: 0.75%;

[0064] Water as the balance.

[0065] Weigh each component according to the above formula and set aside. Under the protection of an inert gas (such as nitrogen), dissolve PEGDA in deionized water to form a PEGDA solution, add HMPP and lactic acid or lactide, and prepare a degradable polymer solution. Finally, use phosphate buffer solution (PBS) to adjust the pH of the degradable polymer solution to 7.35 - 7.45. Among them, lactic acid or lactide can reduce the cross-linking density of PEGDA, thereby increasing its degradation rate in the body; the use of phosphate buffer solution ensures the solubility and stability of the formed protective sheath in the in vivo environment.

[0066] S3. Preparation of the protective sheath:

[0067] (1) Use a balloon folding machine to perform a split folding process on the balloon 1. As Figure 5 shown, the balloon 1 forms multiple lobes 11, and the multiple lobes 11 are wound together;

[0068] (2) Pass the degradable polymer solution into the container 3 through a liquid feeding mechanism, then insert the folded balloon 1 into the relaxed restricting member 4 and immerse it in the degradable polymer solution for 20 - 60 s. Perform a vacuum treatment on the balloon catheter to make the inside of the balloon catheter in a vacuum environment or a low-pressure environment to prevent air or bubbles from entering the balloon 1;

[0069] (3) Pressurize the container 3 to keep the pressure inside the container 3 at 0.15 MPa and maintain it for 1 - 3 minutes to ensure that the solution is evenly distributed on the entire surface of the balloon 1 without bubbles and can penetrate into each fold of the balloon 1; then the driving mechanism drives the upper end of the restricting member 4 to move upward, and the restricting member 4 switches from the relaxed state to the tightened state and squeezes the balloon 1, so that the excess degradable polymer solution on the surface of the balloon 1 oozes out and drops from the mesh holes;

[0070] (4) Drain the degradable polymer solution in the container 3 through the liquid supply mechanism, start the curing mechanism to cure the degradable polymer solution on the surface of the balloon 1, and in-situ form a protective sleeve. The curing is carried out by irradiating with ultraviolet light, the wavelength of the ultraviolet light is 365 nm, and the curing process is controlled within 1 - 2 minutes. Specifically, it can be finely adjusted according to the crosslinking rate of the PEGDA formulation and the intensity of the ultraviolet light source to ensure that the ultraviolet light source evenly irradiates the surface of the balloon 1 to avoid incomplete local curing or over-curing;

[0071] (5) After the curing is completed, the driving mechanism drives the upper end of the restricting member 4 to move downward, the restricting member 4 switches from the tightened state to the relaxed state, releases the negative pressure state of the balloon catheter, and removes the balloon catheter;

[0072] (6) Check the thickness of the protective sleeve layer 8 of the protective sleeve (in this embodiment, the thickness of the protective sleeve layer 8 is 0.1 mm ± 0.02 mm), and conduct a dissolution test on the protective sleeve, including placing the balloon 1 with the protective sleeve in a phosphate buffer solution (pH = 7.4) at 37°C and observing the dissolution rate of the protective sleeve. After testing, the protective sleeve completely dissolves within 30 minutes, and the dissolution products do not form particle residues and there is no risk of blocking blood vessels.

[0073] (7) Store the balloon catheter in an environment with a temperature of 4 - 25°C and a humidity of 3 - 50% to maintain the stability of the coating and avoid the influence of too high temperature or excessive moisture on the degradation characteristics of the protective layer.

[0074] The above embodiments are only used to illustrate the technical concept and features of the present invention, and their purpose is to enable those familiar with this technology to understand the content of the present invention and implement it accordingly, and cannot be used to limit the protection scope of the present invention. All equivalent changes or modifications made according to the spirit and essence of the present invention should be covered within the protection scope of the present invention.

Claims

1. A method for preparing a balloon catheter protective cover, the balloon catheter comprising a catheter (2) and a balloon (1) disposed on the catheter (2) and capable of expansion or contraction, characterized in that: The balloon (1) is subjected to a petal folding process, and then the protective cover is formed on the balloon (1) using a protective cover forming device, the protective cover forming device comprising a container (3), a restriction member (4) movably arranged in the container (3) and having a relaxed state and a tightened state, a driving mechanism connected to the restriction member (4) and used to drive the restriction member (4) to switch between the relaxed state and the tightened state, a curing mechanism arranged in the container (3), and a liquid material mechanism connected to the container (3) and used to pass a raw material liquid into or out of the container (3), Using the protective cover forming device to form the protective cover on the balloon (1) comprises the following steps: a. introducing a raw material liquid into the container (3) through the feed liquid mechanism, then inserting the folded balloon (1) into the restriction member (4) in a relaxed state and immersing it in the raw material liquid, and performing a vacuum treatment on the balloon catheter so that the interior of the balloon catheter is in a vacuum environment or a low-pressure environment, wherein the raw material liquid is a degradable polymer solution; b. The driving mechanism drives the limiting member (4) to switch from a relaxed state to a tightened state, thereby removing excess degradable polymer solution on the surface of the balloon (1); c. The degradable polymer solution in the container (3) is discharged through the feed liquid mechanism, and the curing mechanism is activated to cure the degradable polymer solution on the surface of the balloon (1), thereby forming the protective cover in situ.

2. The method for preparing the balloon catheter protective cover according to claim 1, characterized in that: The limiting member (4) is a mesh-shaped annular structure. When the limiting member (4) switches from a relaxed state to a tightened state, the inner diameter of at least part of the limiting member (4) is reduced and can squeeze the balloon (1).

3. The method for preparing the balloon catheter protective cover according to claim 2, characterized in that: When the limiting member (4) is in a tightened state, the limiting member (4) has a small diameter in the middle and large diameters at the upper and lower ends.

4. The method for preparing the balloon catheter protective cover according to claim 3, characterized in that: When the limiting member (4) is in a tightened state, the limiting member (4) is in an hourglass shape.

5. The method for preparing the balloon catheter protective cover according to claim 1, characterized in that: The driving mechanism is connected to at least one of the upper and lower ends of the limiting member (4), and is capable of driving the end to move in a direction away from the other end so that the limiting member (4) switches to a tightened state; or to move in a direction close to the other end so that the limiting member (4) switches to a relaxed state.

6. The method for preparing the balloon catheter protective cover according to claim 5, characterized in that: The driving mechanism comprises a slide rail (5) extending in the height direction of the container (3), two connecting members (6) respectively arranged at the upper and lower ends of the slide rail (5), and a driving member, the upper end and the lower end of the limiting member (4) are respectively connected to the two connecting members (6), at least one of the two connecting members (6) is connected to the driving member and can slide along the extension direction of the slide rail (5) under the drive of the driving member, The driving mechanism has two groups which are symmetrically arranged outside the limiting member (4).

7. The method for preparing the balloon catheter protective cover according to claim 1, characterized in that: The preparation method further comprises, after step a and before step b, pressurizing the container (3) to control the pressure in the container (3) to be 0.11 to 0.2 Mpa and maintaining the pressure for 1 to 3 minutes.

8. The method for preparing the balloon catheter protective cover according to claim 1, characterized in that: The step a comprises immersing the restriction member (4) in the degradable polymer solution for 20 to 60 seconds, and then performing a vacuum treatment on the balloon catheter.

9. The method for preparing a balloon catheter protective cover according to claim 1, characterized in that: The curing mechanism comprises a plurality of ultraviolet irradiation lamps (7) arranged in the container (3) along the inner circumference of the container (3).

10. The method for preparing the balloon catheter protective cover according to claim 1, characterized in that: The preparation method further comprises the step of, after step c, causing the driving mechanism to drive the limiting member (4) to switch from a tightened state to a relaxed state, and then removing the balloon catheter.

11. The method for preparing the balloon catheter protective cover according to claim 1, characterized in that: Taking the total mass of the degradable polymer solution as 100%, the degradable polymer solution comprises: Polyethylene glycol diacrylate 5-10%, Photoinitiator 0.1~2.5%, Dissolution promoter 0.5~1%, Solvent Residue.

12. The method for preparing the balloon catheter protective cover according to claim 11, characterized in that: The number average molecular weight of the polyethylene glycol diacrylate is 700 to 1000; and / or, The photoinitiator is 2-hydroxy-2-methyl-1-phenyl-1-propanone; and / or, The dissolution promoter is lactic acid and / or lactide; and / or, The solvent is water.

Images