Preparation method of easy-to-sew woven artificial blood vessel

Abstract

The invention belongs to the technical field of biomedical material manufacturing, and particularly relates to a preparation method of an easy-to-suture woven artificial blood vessel. According to the invention, untwisted polyester filament yarns are used as core yarns, and water-soluble vinylon is used as wrap yarns, so that polyester wrap yarns are prepared; and then washing with water to dissolve the water-soluble vinylon filaments, then carrying out coating and densification treatment, and then carrying out coating again to prepare the easy-to-sew woven artificial blood vessel. The easy-to-suture woven artificial blood vessel prepared by the method is soft and fluffy, the surgical suture difficulty is reduced, and endothelial cell adhesion growth is facilitated. The fastness and uniformity of the coating are improved through two times of coating and densification treatment, and the permeability of the easy-to-sew woven artificial blood vessel is effectively reduced.

Description

Technical Field

[0001] The patent of this invention relates to the technical field of biomedical material manufacturing, and specifically to a method for preparing an easy-to-suture braided artificial blood vessel. Background Art

[0002] The impermeability and sutureability of the coating of artificial blood vessels are key evaluation indicators for the success of the operation. At present, in order to increase the density of the blank tube and improve the impermeability, the warp yarn uses 30-150D yarn and adopts high-density weaving technology. In order to make the weaving go smoothly, the warp yarn will be sized, but the ultra-high density makes the slurry not cleanly removed, which affects the biocompatibility of vascular products. To solve this problem, the braided blood vessels currently under development in China are basically woven with twisted yarns, and then undergo a series of treatments to finally obtain artificial blood vessels, but the problem is that it feels hard and the suture needle is difficult to enter and exit, affecting the surgical operation. Secondly, the twisted yarns are highly entangled with each other, which will also affect the coating effect of the pre-coagulation coating, making it difficult for the coating to penetrate between the fibers, and it is easy to "sweat" during the operation, reducing the success rate of the operation. Summary of the invention

[0003] In order to solve the problems existing in the above-mentioned prior art, the present invention provides a method for preparing an easy-to-suture braided artificial blood vessel, wherein the coated yarn of untwisted polyester filaments coated with water-soluble vinylon filaments is used to weave the easy-to-suture braided artificial blood vessel blank tube, the vinylon is removed by washing, and then the coating, densification treatment, patterning, and re-coating are performed. The obtained easy-to-suture braided artificial blood vessel is soft and fluffy, which reduces the difficulty of surgical suturing and is conducive to the attachment and growth of endothelial cells. The two coatings and densification treatments increase the fastness and uniformity of the coating and effectively reduce the permeability of the easy-to-suture braided artificial blood vessel.

[0004] In order to achieve the above technical objectives, the present invention provides a method for preparing an easy-to-suture braided artificial blood vessel, and the technical solution adopted is:

[0005] (1) Using 50-120D FDY untwisted polyester filaments as core yarns and high-temperature water-soluble vinyl filaments as covering yarns, the vinyl filaments are evenly covered on the surface of the polyester filaments by a covering device to obtain polyester covered yarns. The high-temperature water-soluble vinyl filaments are filaments that are soluble in water at 90°C, and the fineness of the vinyl filaments is 50-100D. When the yarns are woven on a machine, the vinyl plays a protective role on the untwisted polyester, preventing the fibers from fuzzing and the yarns from breaking, so that the weaving can proceed smoothly.

[0006] (2) The polyester coated yarn obtained in step (1) is woven into a blank tube through an artificial blood vessel weaving device.

[0007] (3) Wash with pure water to dissolve the vinylon filaments on the blank tube obtained in step (2). The bath ratio is 1:30, and the hot water is washed twice at 95-100°C, each washing lasts 10-30 minutes, then washed 1-2 times with warm water at 60-70°C, and then washed 1-2 times with normal temperature water; repeat the whole washing process 2-3 times and then dry at 60°C.

[0008] (4) Using a polycarbonate-based polyurethane solution with a weight fraction of 0.5-3% as coating solution I, the blank tube obtained in step (3) is coated by a dip coating method, and after coating, it is dried at a temperature of 40-80° C. for 60-90 minutes. The fibers of the blank tube without the vinylon filaments are relatively loose, which is conducive to the coating solution I to infiltrate each fiber.

[0009] (5) The blank tube obtained in step (4) is put on a hollow tube of corresponding size, and treated with dry hot air at 180-220° C. for 120-500 seconds to shrink the polyester filaments at high temperature and perform densification treatment. After the densification treatment, the fiber bundles and fibers are tightly embraced, the density of the blank tube is increased, the porosity is reduced, and the coating is wrapped therein, which is beneficial to improving the fastness and uniformity of the coating.

[0010] (6) The coated tube obtained in step (5) is placed into a texture forming mold of corresponding size for texture forming to obtain a textured tube.

[0011] (7) coating the patterned blank tube obtained in step (6) with coating solution II by using a coating method selected from the group consisting of perfusion coating and immersion coating. After coating, the tube is dried at a temperature of 37 to 60° C. for 2 to 3 hours to obtain an easily sutureable braided artificial blood vessel.

[0012] The effective component of the coating solution II is one of gelatin and collagen, with a weight fraction of 0.5-10%. The gelatin is bovine bone gelatin with a dynamic value of 200-300 Bloomg, and the collagen is type I collagen.

[0013] The coating solution II also contains a toughening agent and a crosslinking agent. The toughening agent is one of glycerol and polyethylene glycol. The glycerol has a purity of 99%, the polyethylene glycol has a molecular weight of 700-2000, and a weight fraction of 1-10%. The crosslinking agent is one of formaldehyde, glutaraldehyde, and genipin, and the weight fraction is 0.04-0.5%.

[0014] Beneficial Effects

[0015] The method for preparing the easy-to-suture braided artificial blood vessel of the present invention uses polyvinyl alcohol-coated polyester filaments as warp yarns, which can greatly reduce the fuzzing and broken filaments of untwisted polyester filaments during the weaving process. After washing, an untwisted artificial blood vessel blank tube is obtained. The blank tube woven in this way is soft and fluffy. The softness can reduce the difficulty of surgical suture, and the fluffiness is conducive to the attachment and growth of endothelial cells. The effective ingredient of the coating solution I is polyurethane. The polyurethane material is a macroscopically smooth and microscopically multiphase-separated structure. It is used for coating to give the artificial blood vessel wall excellent anti-coagulation properties. After densification treatment, the fiber shrinks and tightly coats the coating solution I between the fibers, which can increase the fastness and uniformity of the coating. Further coating of the patterned blank tube improves the biocompatibility of the artificial blood vessel and further effectively reduces the permeability of the artificial blood vessel. DETAILED DESCRIPTION

[0016] In order to further understand the present invention, the present invention is described below in conjunction with embodiments, but it should be understood that these descriptions are only for further illustrating the features and advantages of the present invention, rather than limiting the claims of the present invention.

[0017] The easy-to-suture braided artificial blood vessels prepared in the embodiment and the comparative example were tested for overall water permeability and puncture strength for comparison. The overall water permeability was tested according to the method of 8.7.2.1.2 Overall water permeability / leakage in YY / T 0500-2021 "Cardiovascular Implants Vascular Prostheses Tubular Vascular Grafts and Vascular Patches". The puncture strength was tested according to the test method in GB / T 23318-2009 "Determination of Puncture Strength of Textiles", and the test was carried out using a push rod A. The artificial blood vessels obtained under the same warp and weft density and the same coating method had a small needle puncture result, which means that the artificial blood vessels have good softness, smooth needle insertion, good sutureability, and reduce the difficulty of suturing during clinical surgery.

[0018] Example 1

[0019] A method for preparing an easy-to-suture braided artificial blood vessel comprises the following steps:

[0020] (1) 120D FDY untwisted polyester filament is selected as the core yarn, and 100D water-soluble vinylon filament is selected as the covering yarn. The vinylon filament is evenly coated on the surface of the polyester filament through a long fiber double twisting machine to obtain the polyester covered yarn, and the selected water-soluble vinylon filament is soluble at 90°C.

[0021] (2) The polyester coated yarn obtained in step (1) is used as the warp yarn and woven into a blank tube using an artificial blood vessel weaving device.

[0022] (3) The blank tube obtained in step (2) is washed twice with pure water at a bath ratio of 1:30 at a temperature of 95-100° C., each washing time for 30 minutes, and then washed twice with warm water at 60-70° C., and then washed twice with normal temperature water. The entire washing process is repeated three times to completely dissolve the vinylon on the braided blank tube, and finally dried at 60° C. to obtain an untwisted polyester braided blank tube.

[0023] (4) Using bio-type DMF as solvent, a polycarbonate-based polyurethane solution with a weight fraction of 3% was stirred and dissolved at 90° C. as coating solution I for 3 hours to ensure that the polycarbonate-based polyurethane was completely dissolved. The coating was carried out by dip coating method, and after coating, it was dried at 80° C. for 90 minutes to obtain a primary coating braided tube.

[0024] (5) Put the primary coating braided tube obtained in step (4) onto The hollow tube is treated with 180℃ dry hot air for 500s to shrink the polyester filaments at high temperature, perform densification treatment, increase the tube density, reduce the porosity, and obtain a coated braided tube.

[0025] (6) Put the coated braided tube obtained in step (5) into The texture forming mold is used for texture forming to obtain a textured blank tube.

[0026] (7) Prepare 0.5% type I collagen coating solution II, and add 1% 99% pure glycerol and 0.5% formaldehyde to the coating solution, and coat the patterned blank tube obtained in step (6) by perfusion coating. After coating, dry it at 37° C. for 2 hours to obtain an easy-to-suture braided artificial blood vessel.

[0027] Comparative Example 1

[0028] The method for preparing a braided artificial blood vessel comprises the following steps:

[0029] (1) 120D FDY untwisted polyester filament was selected as the core yarn, and the polyester filament was twisted at 400 twists / m through a long fiber double twisting machine.

[0030] (2) The twisted polyester filaments obtained in step (1) are used as warp yarns and woven into a blank tube using an artificial blood vessel weaving device.

[0031] (3) According to steps (4), (5), (6) and (7) of the method for preparing an easily sutureable braided artificial blood vessel in Example 1, a braided artificial blood vessel is prepared.

[0032] Example 2

[0033] A method for preparing an easy-to-suture braided artificial blood vessel comprises the following steps:

[0034] (1) 80D FDY untwisted polyester filament is selected as the core yarn, and 80D water-soluble vinylon filament is selected as the covering yarn. The vinylon filament is evenly coated on the surface of the polyester filament through a long fiber double twisting machine to obtain the polyester covered yarn, and the selected water-soluble vinylon filament is soluble at 90°C.

[0035] (2) The polyester coated yarn obtained in step (1) is used as the warp yarn and woven into a blank tube using an artificial blood vessel weaving device.

[0036] (3) The blank tube obtained in step (2) is washed twice with hot water at a bath ratio of 1:30 at a temperature of 95 to 100° C., each washing for 20 minutes, and then washed once with warm water at 60 to 70° C. and once with water at room temperature. The entire washing process is repeated three times to completely dissolve the vinylon on the braided blank tube, and finally dried at 60° C. to obtain an untwisted polyester braided blank tube.

[0037] (4) Using bio-type DMF as solvent, a polycarbonate-based polyurethane solution with a weight fraction of 0.5% was stirred and dissolved at 90° C. for 2 hours to ensure that the polycarbonate-based polyurethane was completely dissolved. The coating was carried out by dip coating method, and after coating, it was dried at 40° C. for 60 minutes to obtain a primary coating braided tube.

[0038] (5) Put the primary coating braided tube obtained in step (4) onto The hollow tube is treated with 200℃ dry hot air for 300s to shrink the polyester filaments at high temperature, perform densification treatment, increase the tube density, reduce the porosity, and obtain a coated braided tube.

[0039] (6) Put the coated braided tube obtained in step (5) into The patterning mold is used for patterning to obtain a patterned blank tube.

[0040] (7) Prepare 10% 250 Bloomg bovine bone gelatin coating solution II, and add 10% polyethylene glycol with a molecular weight of 2000 and 0.04% glutaraldehyde to the coating solution, and coat the patterned blank tube obtained in step (6) by perfusion coating. After coating, dry it at 60°C for 3 hours to obtain an easy-to-suture braided artificial blood vessel.

[0041] Comparative Example 2

[0042] The method for preparing a braided artificial blood vessel comprises the following steps:

[0043] (1) 100D FDY untwisted polyester filament was selected as the core yarn, and the polyester filament was twisted at 400 twists / m through a long fiber double twisting machine.

[0044] (2) The twisted polyester filaments obtained in step (1) are used as warp yarns and woven into a blank tube using an artificial blood vessel weaving device.

[0045] (3) According to steps (4), (5), (6) and (7) of the method for preparing an easily sutureable braided artificial blood vessel in Example 2, a braided artificial blood vessel is prepared.

[0046] Example 3

[0047] A method for preparing an easy-to-suture braided artificial blood vessel comprises the following steps:

[0048] (1) 50D FDY untwisted polyester filament is selected as the core yarn, and 50D water-soluble vinylon filament is selected as the covering yarn. The vinylon filament is evenly coated on the surface of the polyester filament through a long fiber double twisting machine to obtain the polyester covered yarn, and the selected water-soluble vinylon filament is soluble at 90°C.

[0049] (2) The polyester coated yarn obtained in step (1) is used as the warp yarn and woven into a blank tube using an artificial blood vessel weaving device.

[0050] (3) The blank tube obtained in step (2) is washed twice with pure water at a bath ratio of 1:30 at a temperature of 95 to 100° C., each washing time for 10 minutes, and then washed once with warm water at 60 to 70° C. and once with water at room temperature. The entire washing process is repeated twice to completely dissolve the vinylon on the braided blank tube, and finally dried at 60° C. to obtain an untwisted polyester braided blank tube.

[0051] (4) Using bio-type DMF as solvent, a polycarbonate-based polyurethane solution with a weight fraction of 1.5% was stirred and dissolved at 90° C. for 3 hours to ensure that the polycarbonate-based polyurethane was completely dissolved. The coating was carried out by dip coating method, and after coating, it was dried at 60° C. for 60 minutes to obtain a primary coating braided tube.

[0052] (5) Put the primary coating braided tube obtained in step (4) onto The hollow tube is treated with 220℃ dry hot air for 120s to shrink the polyester filaments at high temperature, perform densification treatment, increase the tube density, reduce the porosity, and obtain a coated braided tube.

[0053] (6) Put the coated braided tube obtained in step (5) into The texture forming mold is used for texture forming to obtain a textured blank tube.

[0054] (7) Prepare a 5% type I collagen coating solution II, and add 5% 99% pure glycerol and 0.3% genipin to the coating solution, and coat the patterned blank tube obtained in step (6) by perfusion coating. After coating, dry it at 50° C. for 3 hours to obtain an easy-to-suture braided artificial blood vessel.

[0055] Comparative Example 3

[0056] The method for preparing a braided artificial blood vessel comprises the following steps:

[0057] (1) 100D FDY untwisted polyester filament was selected as the core yarn, and the polyester filament was twisted at 400 twists / m through a long fiber double twisting machine.

[0058] (2) The twisted polyester filaments obtained in step (1) are used as warp yarns and woven into a blank tube using an artificial blood vessel weaving device.

[0059] (3) According to steps (4), (5), (6) and (7) of the method for preparing an easily sutureable braided artificial blood vessel in Example 3, a braided artificial blood vessel is prepared.

[0060] The overall water permeability test results under 120 mmHg: Before coating, the easily sutured braided artificial blood vessels of Examples 1 to 3 and Comparative Examples 1 to 3 had serious water leakage, with the maximum leakage reaching 271.58 ml / cm 2 ·min, after coating, the leakage of the easily sutured braided artificial blood vessels of Examples 1 to 3 and Comparative Examples 1 to 3 was 0.

[0061] Puncture strength test results: The puncture strengths of Examples 1 to 3 are all lower than those of Comparative Examples 1 to 3 with the same warp and weft density and the same coating method, which indicates that the embodiments improve the softness of the artificial blood vessels and reduce the difficulty of suturing during clinical surgery.

[0062] Table 1 Comparison of puncture strength between the embodiments of the present invention and the comparative examples

[0063] Example 1 Comparative Example 1 Example 2 Comparative Example 2 Example 3 Comparative Example 3 Puncture strength(N) 18.2 21.5 22.1 24.7 22.4 24.9

Claims

1. A method for preparing an easy-to-suture braided artificial blood vessel, characterized in that: The following steps are involved: (1) Using untwisted polyester filaments as core yarns and water-soluble vinyl filaments as covering yarns, the vinyl filaments are evenly covered on the surface of the polyester filaments by a covering device to prepare polyester covered yarns; the water-soluble vinyl filaments are high-temperature water-soluble vinyl, which is soluble in water at 90°C; (2) weaving the polyester coated yarn obtained in step (1) into a blank tube through an artificial blood vessel weaving device; (3) The blank tube obtained in step (2) is washed twice with pure water at a bath ratio of 1:30 at a temperature of 95 to 100° C., each washing lasting 10 to 30 minutes, then washed 1 to 2 times with warm water at 60 to 70° C., and then washed 1 to 2 times with water at room temperature; the whole washing process is repeated 2 to 3 times to dissolve the water-soluble vinylon filaments, and then dried at 60° C.; (4) coating the blank tube obtained in step (3) with the coating solution I by dip coating, and drying at a temperature of 40 to 80° C. for 60 to 90 minutes after coating; (5) putting the blank tube obtained in step (4) onto a hollow tube of corresponding size, treating it with dry hot air at 180 to 220° C. for 120 to 500 seconds to shrink the polyester filaments at high temperature, perform densification treatment, increase the density of the blank tube, and reduce the porosity; (6) putting the blank tube obtained in step (5) onto a texture forming mold of corresponding size to form a texture, thereby obtaining a textured blank tube; (7) The patterned blank tube obtained in step (6) is perfused or dipped with the coating solution II, and after coating, it is dried at a temperature of 37 to 60° C. for 2 to 3 hours.

2. The method for preparing the easy-to-suture braided artificial blood vessel according to claim 1, characterized in that: The untwisted polyester filament described in step (1) is FDY yarn with a fineness of 50 to 120D, and the water-soluble vinylon filament has a fineness of 50 to 100D.

3. The method for preparing the easy-to-suture braided artificial blood vessel according to claim 1, characterized in that: The effective component of the coating solution I described in step (4) is polycarbonate-based polyurethane, with a weight fraction of 0.5 to 3%.

4. The method for preparing the easy-to-suture braided artificial blood vessel according to claim 1, characterized in that: The effective ingredient of the coating solution II described in step (7) is one of gelatin and collagen, with a weight fraction of 0.5 to 10%.

5. The method for preparing the easy-to-suture braided artificial blood vessel according to claim 4, characterized in that: The gelatin is bovine bone gelatin with a dynamic value of 200-300 Bloomg, and the collagen is type I collagen.

6. The method for preparing the easy-to-suture braided artificial blood vessel according to claim 4, characterized in that: The coating solution II described in step (7) also contains a toughening agent and a crosslinking agent, wherein the toughening agent is one of glycerol and polyethylene glycol, with a weight fraction of 1 to 10%; the crosslinking agent is one of formaldehyde, glutaraldehyde and genipin, with a weight fraction of 0.04 to 0.5%.

7. The method for preparing the easily sutured braided artificial blood vessel according to claim 6, characterized in that: The purity of the glycerol is 99%, and the molecular weight of the polyethylene glycol is 700-2000.