Integrally-formed artificial blood vessel with three-layer bionic structure

Abstract

The utility model relates to an integrally-formed artificial blood vessel with a three-layer bionic structure. The artificial blood vessel of the three-layer bionic structure comprises an inner layer, a middle layer and a surface layer, the inner layer is arranged to be a plain weave of the inner layer, the middle layer is arranged to be a crepe weave, and the surface layer is arranged to be a transverse raised line weave; the warp yarns of the middle layer are interwoven and connected with the weft yarns of the inner layer, and the warp yarns of the middle layer are interwoven and connected with the weft yarns of the surface layer, so that the inner layer, the middle layer and the surface layer are connected. Compared with a composite artificial blood vessel with a multi-layer structure, the integrally woven three-layer structure has the advantages that the layers are combined more firmly, the problem of separation of the layers does not exist, meanwhile, the bonding procedure between the layers is reduced, and the process is simplified.

Description

Technical Field

[0001] This utility model relates to the field of medical device technology, specifically to an integrally molded three-layer biomimetic artificial blood vessel. Background Technology

[0002] Cardiovascular diseases are diverse, and the number of patients is increasing year by year. Implantation or replacement of artificial blood vessels is a major treatment method for cardiovascular diseases, thus the demand for artificial blood vessels is also increasing annually. Human blood vessels consist of three layers: the intima, media, and adventitia. Single-layer artificial blood vessels differ significantly from natural blood vessels in structure and have inferior mechanical properties. Therefore, the development of multi-layered artificial blood vessels represents the future direction of artificial blood vessel development.

[0003] Currently, existing technologies have disclosed several multi-layered artificial blood vessels and their preparation methods. For example, patent CN111000661 A, titled "A Composite Artificial Blood Vessel and Its Preparation Method," uses electrospinning to prepare a double-layered tubular artificial blood vessel. The double-layered structure consists of an inner first nanofiber layer and an outer second nanofiber layer bonded together. Patent CN106178120 A, titled "A Biomimetic Natural Blood Vessel Three-Layer Composite Material Vascular Stent and Its Preparation Method," prepares a three-layered composite vascular stent. PLGA and SF are blended in a solvent to obtain a spinning solution. PLGA / SF yarn is produced using spinning equipment. PLCL and COL are blended in a solvent to obtain a spinning solution. Spinning yields the inner vascular layer. The PLGA / SF yarn is radially wound around the outer layer to obtain a tubular stent. The PLCL / COL spinning solution yields an outer layer of irregular nanofibers. After drying, a three-layered vascular stent is obtained. The patent with publication number CN 113476661 A is entitled "A Three-Layer Composite Self-Healing Artificial Blood Vessel and Its Preparation Method". This utility model discloses a three-layer composite self-healing artificial blood vessel, in which zwitterionic hydrogel is used as the inner and outer layers and self-healing polyurethane elastomer is used as the middle layer. The middle layer is prepared by a mold forming method, and then the polyurethane elastomer middle layer is placed in zwitterionic hydrogel and coated with inner and outer layers to obtain a three-layer artificial blood vessel.

[0004] However, the above patents all involve multi-layered artificial blood vessels, requiring the separate fabrication of each layer. These layers then undergo multiple processes such as winding and coating to bond them together. The methods for fabricating multi-layered artificial blood vessels are cumbersome and suffer from issues such as poor bonding between layers. Therefore, to address the cumbersome process and obtain blood vessels similar to natural structures, this invention designs a one-piece, three-layered biomimetic artificial blood vessel. Utility Model Content

[0005] The technical problem to be solved by this invention is to provide a one-piece molded three-layer biomimetic artificial blood vessel. The aim is to solve the problem of poor adhesion between the layers in existing artificial blood vessels.

[0006] The technical solution of this utility model to solve the above-mentioned technical problems is as follows: an integrally formed three-layer biomimetic artificial blood vessel, the three-layer biomimetic artificial blood vessel including an inner layer, a middle layer and a surface layer, the inner layer is set as a plain weave, the middle layer is set as a crepe weave, and the surface layer is set as a transverse rib weave; the warp yarns of the middle layer are interwoven with the weft yarns of the inner layer, and the warp yarns of the middle layer are interwoven with the weft yarns of the surface layer, so that the inner layer, the middle layer and the surface layer are connected.

[0007] The beneficial effects of this invention are as follows: The three-layer artificial blood vessel structure is integrally woven using a machine weaving process, echoing the three-layer structure of human blood vessels, enhancing the biomimetic effect of the artificial blood vessel, and enabling the blood vessel to better adapt to environmental changes within the body after implantation. The inner, middle, and outer layers are designed with three different tissue structures: the inner layer uses plain weave, the middle layer uses crepe weave, and the outer layer uses transverse convex stripe weave. The pore diameter gradually increases from the inside to the outside, facilitating cell ingrowth, endothelialization of the blood vessel, and giving the artificial blood vessel excellent anti-leakage properties, compliance, and mechanical properties. Compared to multi-layer artificial blood vessels composed of composite structures, the integrally woven three-layer structure has a stronger bond between layers, eliminating the problem of layer separation, and reducing the bonding process between layers, thus simplifying the procedure.

[0008] Based on the above technical solution, the present invention can be further improved as follows.

[0009] Among them, plain weave has the most interlacing points of warp and weft yarns. The resulting fabric surface is dense and smooth, similar to the smooth inner wall of natural blood vessels. With its smooth surface and small pores, it can be designed as the inner layer of artificial blood vessels, which can also prevent blood leakage to a certain extent.

[0010] Furthermore, the transverse convex stripe structure includes a warp plain weave and a surface plain weave. The warp plain weave is provided with floats, and the weft yarns of the floats are gathered together under the tension of the surface plain weave to form transverse convexities.

[0011] The beneficial effects of adopting the above-mentioned further scheme are: the transverse convex stripe structure gives the surface of the artificial blood vessel a wavy effect, eliminating the need for the wavy treatment step and simplifying the artificial blood vessel production process; and the transverse convex stripe structure has fewer warp and weft yarn interlacing points, so the weft yarn has a larger range of movement when subjected to external force, and has good elasticity.

[0012] Furthermore, the warp points of the crepe fabric are floating, and the weft points are sinking. The warp and weft points are arranged regularly to form several elastic protrusions.

[0013] The beneficial effects of adopting the above-mentioned further scheme are as follows: the crepe structure is designed by adding points on the basis of the plain weave structure. The difference between it and the inner plain weave structure and the surface horizontal convex strip structure composed of plain weave and warp-reinforced plain weave is not too large, which reduces the complexity of the weaving process. The warp points of the crepe structure are floating and the weft points are sinking. The regular arrangement of the warp and weft points forms several elastic protrusions. On the one hand, it connects the inner plain weave structure and the surface horizontal convex strip structure well, playing a good transition role. On the other hand, it improves the compliance of artificial blood vessels to a certain extent.

[0014] Furthermore, the inner diameter of the three-layer biomimetic artificial blood vessel is 10mm-32mm; the length of the three-layer biomimetic artificial blood vessel is 10cm-60cm.

[0015] Furthermore, the thickness ratio of the inner layer, the middle layer, and the outer layer is 9:11:17.

[0016] Furthermore, the warp yarns of the inner layer, the middle layer, and the outer layer are all polyester stretch textured yarns.

[0017] Furthermore, the polyester stretch textured yarn is provided with network dots.

[0018] Furthermore, each meter of the polyester stretch textured yarn has 150-180 network points.

[0019] Furthermore, the surface of the polyester stretch textured yarn is provided with a surface coating.

[0020] The beneficial effects of adopting the above-mentioned further solutions are: improving the anticoagulant and biocompatibility of the yarn through surface coating, thus avoiding the pre-coagulation process before surgery.

[0021] Furthermore, the thickness of the surface coating is 0.02mm-0.05mm. Attached Figure Description

[0022] Figure 1 This is a schematic diagram of the inner layer structure of this utility model;

[0023] Figure 2 This is a schematic diagram of the middle layer structure of this utility model;

[0024] Figure 3 This is a schematic diagram of the surface structure of this utility model;

[0025] Figure 4This is a schematic diagram of the three-layer connection structure of the present invention, which consists of a middle layer connecting to the inner layer and a middle layer connecting to the outer layer.

[0026] Figure 5 This is a schematic diagram of the structure of the three-layer tubular tissue of this utility model;

[0027] The attached diagram lists the components represented by each number as follows:

[0028] 1-Inner layer, 2-Middle layer, 3-Top layer. Detailed Implementation

[0029] The principles and features of this utility model are described below with reference to the accompanying drawings. The examples given are only for explaining this utility model and are not intended to limit the scope of this utility model.

[0030] Example

[0031] This embodiment relates to a one-piece molded three-layer biomimetic artificial blood vessel. Figure 1-5 The three-layer biomimetic artificial blood vessel includes an inner layer 1 ( Figure 1 ), middle layer 2 ( Figure 2 ) and surface 3 ( Figure 3 The inner layer 1 is configured with a plain weave, the middle layer 2 is configured with a crepe weave, and the outer layer 3 is configured with a ribbed weave. The warp yarns of the middle layer 2 are interwoven with the weft yarns of the inner layer 1, and the warp yarns of the middle layer 2 are interwoven with the weft yarns of the outer layer 3, thereby connecting the inner layer 1, the middle layer 2, and the outer layer 3. Figure 4 ).

[0032] Among them, plain weave is the weave structure with the most interlacing points of warp and weft yarns. The resulting fabric surface is dense and smooth, similar to the smooth inner wall of natural blood vessels. With its smooth surface and small pores, it can be designed as the inner layer of artificial blood vessels, which can also prevent blood leakage to a certain extent.

[0033] In this preferred embodiment, the transverse convex stripe structure includes a warp-faced plain weave and a surface layer 3 plain weave. The warp-faced plain weave is provided with float yarns, which, under the tension of the surface layer 3 plain weave, gather the weft yarns to form transverse convexities. The transverse convex stripe structure gives the artificial blood vessel surface a wavy effect, eliminating the need for a wavy treatment step and simplifying the artificial blood vessel production process. Furthermore, the transverse convex stripe structure has fewer warp and weft yarn interlacing points, allowing for a larger range of weft yarn movement under external force, resulting in good elasticity.

[0034] In this preferred embodiment, the warp points of the crepe fabric are floating, and the weft points are sinking. The warp and weft points are arranged regularly to form several elastic protrusions. The crepe fabric is designed using an additive method based on plain weave. The difference between it and the plain weave of the inner layer 1 and the transverse convex strip weave of the outer layer 3, which consists of plain weave and warp-reinforced plain weave, is not too great, reducing the complexity of the weaving process. The floating warp points and sinking weft points of the crepe fabric, with their regular arrangement forming several elastic protrusions, effectively connect the plain weave of the inner layer 1 and the transverse convex strip weave of the outer layer 3, providing a good transition. Furthermore, it improves the compliance of the artificial blood vessel to a certain extent.

[0035] In this preferred embodiment, the inner diameter of the three-layer biomimetic artificial blood vessel is 10mm-32mm, such as 10mm, 15mm, 20mm, 32mm, etc.; the length of the three-layer biomimetic artificial blood vessel is 10cm-60cm, such as 10cm, 20cm, 30cm, 60cm, etc.

[0036] In this preferred embodiment, the thickness ratio of the inner layer 1, the middle layer 2, and the surface layer 3 is 9:11:17.

[0037] In this preferred embodiment, the warp yarns of the inner layer 1, the middle layer 2, and the outer layer 3 are all polyester stretch textured yarns.

[0038] In this preferred embodiment, the polyester textured yarn is provided with network dots. Each meter of the polyester textured yarn has 150-180 network dots.

[0039] In this preferred embodiment, the surface of the polyester stretch textured yarn is provided with a surface coating. The surface coating improves the yarn's anticoagulant and biocompatibility, avoiding the need for a pre-coagulation process before surgery.

[0040] This embodiment relates to a method for fabricating a one-piece, three-layer biomimetic artificial blood vessel, which includes the following specific steps:

[0041] (1) The raw material PET chips are pre-crystallized at a temperature of 120℃-170℃ or above and a crystallization time of 30 min. Then they are dried in a dryer at a temperature of 170℃ for 8 h. After that, they are melt-extruded by a screw extruder and then spun into 60-80 denier polyester filaments by a spinning machine at a spinning speed of 1500 m / min-3000 m / min. Then they are drawn and deformed to produce polyester textured yarn (DTY) with a draw ratio of 1.5-2. Polyester DTY has many network points of 150-180 network points / meter, which has both good bulkiness and good elasticity.

[0042] (2) Prepare heparin sodium solution. Take heparin and physiological saline at a ratio of 1:100 to prepare heparin sodium solution. Add the prepared heparin sodium solution to the sizing tank of the sizing machine. The spun polyester DTY filament passes through the sizing machine. Part of the sizing solution penetrates into the fiber and part remains on the yarn surface. The surface coating thickness is about 0.02mm-0.05mm. After drying, the yarn is given certain anticoagulant properties. At the same time, after sizing, the yarn surface is smooth and easy to weave.

[0043] (3) Use spun polyester DTY as warp and weft yarns to weave artificial blood vessels, with a warp and weft density of 500-800 yarns / 10cm.

[0044] (4) Thread the warp yarns into the heddle holes using the forward threading method. Select a reed size of 80 reeds / 10cm and thread 12 warp yarns into each reed hole.

[0045] (5) Input the designed weave diagram into the jacquard loom and weave the artificial blood vessel;

[0046] (6) Place the woven tube blank onto a stainless steel cylindrical mold of the corresponding size, set the temperature to 170℃, and the time to 10min. Then place it in a vacuum drying oven to dry, thereby obtaining a three-layer biomimetic artificial blood vessel.

[0047] In summary, this invention utilizes a machine-woven three-layer artificial blood vessel structure, echoing the three-layer structure of human blood vessels, thus enhancing the biomimetic effect of the artificial blood vessel and enabling it to better adapt to environmental changes within the body after implantation. The inner layer 1, middle layer 2, and outer layer 3 are designed with three different tissue structures: the inner layer 1 uses a plain weave, the middle layer 2 uses a crepe weave, and the outer layer uses a transverse convex stripe weave. The pore diameter gradually increases from the inside out, facilitating cell ingrowth, endothelialization of the blood vessel, and giving the artificial blood vessel excellent anti-leakage properties, compliance, and mechanical properties. Compared to multi-layered artificial blood vessels, the integrated three-layer structure provides a stronger bond between layers, eliminating the problem of layer separation and reducing the need for bonding between layers, thus simplifying the process.

[0048] In the description of this specification, the references to terms such as "one embodiment," "some embodiments," "example," "specific example," or "some examples," etc., indicate that a specific feature, structure, material, or characteristic described in connection with that embodiment or example is included in at least one embodiment or example of the present invention. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples. Moreover, without contradiction, those skilled in the art can combine and integrate the different embodiments or examples described in this specification, as well as the features of different embodiments or examples.

[0049] Although embodiments of the present invention have been shown and described above, it is understood that the above embodiments are exemplary and should not be construed as limiting the present invention. Those skilled in the art can make changes, modifications, substitutions and variations to the above embodiments within the scope of the present invention.

Claims

1. A one-piece molded three-layer biomimetic artificial blood vessel, wherein the three-layer biomimetic artificial blood vessel comprises an inner layer, a middle layer, and a surface layer, characterized in that, The inner layer is configured with a plain weave, the middle layer with a crepe weave, and the outer layer with a ribbed weave. The warp yarns of the middle layer are interwoven with the weft yarns of the inner layer, and the warp yarns of the middle layer are interwoven with the weft yarns of the outer layer, thereby connecting the inner layer, the middle layer, and the outer layer.

2. The integrally molded three-layer biomimetic artificial blood vessel according to claim 1, characterized in that, The transverse convex stripe structure includes a warp plain weave and a surface plain weave. The warp plain weave is provided with floats, and the floats are gathered by the weft yarns under the tension of the surface plain weave to form transverse convexities.

3. The integrally molded three-layer biomimetic artificial blood vessel according to claim 1, characterized in that, The warp points of the crepe fabric are floating, and the weft points are sinking. The warp and weft points are arranged regularly to form several elastic protrusions.

4. The integrally molded three-layer biomimetic artificial blood vessel according to claim 1, characterized in that, The inner diameter of the three-layer biomimetic artificial blood vessel is 10mm-32mm; the length of the three-layer biomimetic artificial blood vessel is 10cm-60cm.

5. The integrally molded three-layer biomimetic artificial blood vessel according to claim 1, characterized in that, The thickness ratio of the inner layer, the middle layer, and the outer layer is 9:11:

17.

6. The integrally molded three-layer biomimetic artificial blood vessel according to any one of claims 1 to 5, characterized in that, The warp yarns of the inner layer, the middle layer, and the outer layer are all polyester stretch textured yarns.

7. The integrally molded three-layer biomimetic artificial blood vessel according to claim 6, characterized in that, The polyester stretch textured yarn is provided with network dots.

8. The integrally molded three-layer biomimetic artificial blood vessel according to claim 7, characterized in that, Each meter of the described polyester stretch textured yarn has 150-180 network points.

9. The integrally molded three-layer biomimetic artificial blood vessel according to claim 6, characterized in that, The surface of the polyester stretch textured yarn is provided with a surface coating.

10. The integrally molded three-layer biomimetic artificial blood vessel according to claim 9, characterized in that, The thickness of the surface coating is 0.02mm-0.05mm.

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