阅读说明：本技术 一种人造血管及其制备方法 (Artificial blood vessel and preparation method thereof ) 是由 姚昊 谷子琦 马晓曼 明景 阙亦云 于 2020-05-13 设计创作，主要内容包括：本发明提供一种人造血管及其制备方法,包括：提供基底层；对所述基底层进行羧基化改性；对羧基化改性后的所述基底层进行涂敷以形成一涂层,所述涂层覆盖所述基底层的表面并填充所述基底层的空隙；以及对所述涂层进行固化,进而形成所述人造血管。由于在对人造血管的基底层进行涂敷之前,对其进行了羧基化改性,故而可以增加所述基底层的亲水性,故后续在对所述基底层进行涂敷时,涂覆溶液可以渗入到所述基底层的纤维间空隙将所述基底层的纤维间空隙填满,使得在临床使用时,不会因人造血管折叠、缝合等操作而破裂,进而引发术后漏血的不良事件。(The invention provides an artificial blood vessel and a preparation method thereof, comprising the following steps: providing a base layer; performing carboxylation modification on the substrate layer; coating the substrate layer after the carboxylation modification to form a coating layer, wherein the coating layer covers the surface of the substrate layer and fills the gap of the substrate layer; and curing the coating to form the artificial blood vessel. The basal layer of the artificial blood vessel is subjected to carboxylation modification before being coated, so that the hydrophilicity of the basal layer can be increased, and a coating solution can penetrate into fiber gaps of the basal layer to fill the fiber gaps of the basal layer when the basal layer is coated, so that the fracture caused by operations such as folding and suturing of the artificial blood vessel and the adverse event of postoperative blood leakage can be avoided when the basal layer is clinically used.)

1. A method for preparing an artificial blood vessel, comprising:

providing a base layer;

performing carboxylation modification on the substrate layer;

coating the substrate layer after the carboxylation modification to form a coating layer, wherein the coating layer covers the surface of the substrate layer and fills the gap of the substrate layer; and

and curing the coating to form the artificial blood vessel.

2. The method of claim 1, wherein the base layer is woven from a fibrous material comprising ester groups, and the base layer is modified by carboxylation by hydrolysis of chemical bonds.

3. The method of preparing a vascular prosthesis according to claim 2, wherein the method of hydrolyzing the chemical bond comprises: and carrying out water bath treatment on the substrate layer by using an alkaline solution.

4. The method for preparing a vascular prosthesis according to claim 3, wherein the temperature of the water bath treatment is 20 to 90 ℃ and the time is 30 to 60 minutes.

5. The method of claim 2, further comprising washing the base layer after the carboxylation modification to neutral PH and drying the base layer before coating the base layer after the carboxylation modification.

6. The method of claim 1, wherein the base layer is woven from a fiber material containing carbon-hydrogen bonds, and the base layer is modified by carboxylation by grafting functional groups.

7. The method of preparing a vascular prosthesis according to claim 6, wherein the grafting of the functional group comprises:

and carrying out primary irradiation on the substrate layer, then immersing the substrate layer into an acrylic acid solution, and carrying out secondary irradiation on the substrate layer with the acrylic acid solution after extrusion by a compression roller.

8. The method of preparing a vascular prosthesis according to claim 7, further comprising disposing the base layer in an inert gas and subjecting the base layer in the inert gas to the first irradiation and the second irradiation.

9. The method for preparing a vascular prosthesis according to claim 7, wherein the acrylic acid solution has a concentration of 10% to 50%.

10. The method of claim 7, further comprising washing the base layer with magnesium hydroxide solution, washing with water and drying before coating the base layer.

11. The method of preparing a vascular prosthesis according to claim 1, wherein the step of coating the base layer after the carboxylation modification comprises:

and placing the base layer after the carboxylation modification in a container, vacuumizing the container, and then coating the base layer after the carboxylation modification.

12. An artificial blood vessel comprising a substrate layer and a coating layer covering a surface of the substrate layer and filling a void of the substrate layer.

13. The vascular prosthesis of claim 12, wherein the vascular prosthesis is prepared by the method of manufacturing a vascular prosthesis according to any one of claims 1 to 11.

Technical Field

The invention relates to the technical field of medical instruments, in particular to an artificial blood vessel and a preparation method thereof.

Background

The artificial blood vessel is mainly used in the operation of replacing or repairing the human autologous blood vessel which is diseased or damaged due to diseases, trauma and other factors, and also has application in bypass and bypass operations. Artificial blood vessels are generally classified into a woven type and a non-woven type, wherein the woven type artificial blood vessel may be made of biocompatible fibers. Weaving methods include knitting, weaving, braiding, and the like.

The basal layer of the artificial blood vessel is a high-gap structure formed by interweaving fibers, and the porous structure is favorable for directional migration, proliferation and differentiation of endothelial cells and smooth muscle cells, accelerates the endothelialization of the blood vessel, and avoids the generation of thrombus and inflammatory reaction. However, the woven blood vessel requires a pre-coagulation treatment before implantation because of a large leakage amount.

In order to solve the above problems, a common method is to impregnate the artificial blood vessel with a degradable biomaterial (albumin, fibroin, collagen, etc.) for coating, and crosslink and cure. In clinical use, however, the coating may be ruptured by folding, suturing, etc. of the blood vessel, thereby causing an adverse event of blood leakage after operation.

Disclosure of Invention

The invention aims to provide an artificial blood vessel and a preparation method thereof, which aim to solve the problem that the coating is easy to crack so as to cause adverse events of postoperative blood leakage.

In order to solve the above technical problems, the present invention provides a method for preparing an artificial blood vessel, comprising:

providing a base layer;

performing carboxylation modification on the substrate layer;

coating the substrate layer after the carboxylation modification to form a coating layer, wherein the coating layer covers the surface of the substrate layer and fills the gap of the substrate layer; and

and curing the coating to form the artificial blood vessel.

Optionally, in the method for preparing the artificial blood vessel, the base layer is woven from a fiber material containing ester groups, and the base layer is subjected to carboxylation modification by a method of hydrolyzing chemical bonds.

Optionally, in the method for preparing a vascular prosthesis, the method for hydrolyzing a chemical bond includes: and carrying out water bath treatment on the substrate layer by using an alkaline solution.

Optionally, in the preparation method of the artificial blood vessel, the temperature of the water bath treatment is 20-90 ℃, and the time is 30-60 min.

Optionally, in the preparation method of the artificial blood vessel, before coating the base layer after the carboxylation modification, the base layer after the carboxylation modification is washed until PH is neutral, and dried.

Optionally, in the preparation method of the artificial blood vessel, the base layer is woven from a fiber material containing a carbon-hydrogen bond, and the base layer is subjected to carboxylation modification by a method of grafting a functional group.

Optionally, in the method for preparing the artificial blood vessel, the method for grafting the functional group includes:

and carrying out primary irradiation on the substrate layer, then immersing the substrate layer into an acrylic acid solution, and carrying out secondary irradiation on the substrate layer with the acrylic acid solution after extrusion by a compression roller.

Optionally, in the method for preparing a vascular prosthesis, the substrate layer is disposed in an inert gas, and the first irradiation and the second irradiation are performed on the substrate layer in the inert gas.

Optionally, in the method for preparing an artificial blood vessel, the concentration of the acrylic acid solution is 10% to 50%.

Optionally, in the preparation method of the artificial blood vessel, before coating the base layer after the carboxylation modification, the base layer after the carboxylation modification is washed by using a magnesium hydroxide solution, and then washed and dried.

Optionally, in the method for preparing an artificial blood vessel, the method for coating the base layer after the carboxylation modification comprises:

and placing the base layer after the carboxylation modification in a container, vacuumizing the container, and then coating the base layer after the carboxylation modification.

The invention also provides an artificial blood vessel which comprises a substrate layer and a coating layer, wherein the coating layer covers the surface of the substrate layer and fills the gap of the substrate layer.

Optionally, in the artificial blood vessel, the artificial blood vessel is prepared by the preparation method of the artificial blood vessel as described above.

The artificial blood vessel and the preparation method thereof provided by the invention comprise the following steps: providing a base layer; performing carboxylation modification on the substrate layer; coating the substrate layer after the carboxylation modification to form a coating layer, wherein the coating layer covers the surface of the substrate layer and fills the gap of the substrate layer; and curing the coating to form the artificial blood vessel. The basal layer of the artificial blood vessel is subjected to carboxylation modification before being coated, wherein carboxyl is a hydrophilic group, so that the carboxylation modification can increase the hydrophilicity of the basal layer, and a coating solution can penetrate into fiber gaps of the basal layer to fill the fiber gaps of the basal layer when the basal layer is coated, so that the basal layer is not cracked due to operations such as folding and suturing of the artificial blood vessel in clinical use, and then adverse events of postoperative blood leakage are not caused.

Drawings

Fig. 1 is a flowchart of a method for preparing a vascular prosthesis according to an embodiment of the present invention;

fig. 2 is a schematic diagram of a carboxylated artificial blood vessel basal layer in an embodiment of the invention.

Detailed Description

The core idea of the invention is to provide an artificial blood vessel and a preparation method thereof, which aim to solve the problem that a coating layer is difficult to permeate into gaps of a basal layer when the artificial blood vessel is prepared.

The applicant found in many years of research that the adverse event of postoperative blood leakage after rupture of the coating layer caused by operations such as folding, suturing, etc. of the blood vessel is caused by the difficulty of the coating layer to penetrate into the voids of the basal layer when preparing the artificial blood vessel, and therefore, the applicant proposed an artificial blood vessel and a preparation method thereof, wherein the coating layer of the artificial blood vessel covers the surface of the basal layer of the artificial blood vessel and fills the voids of the basal layer.

In order to realize the idea, the invention provides a preparation method of an artificial blood vessel, which comprises the following steps: providing a woven substrate layer; performing carboxylation modification on the substrate layer; coating the substrate layer after the carboxylation modification to form a coating layer, wherein the coating layer covers the surface of the substrate layer and fills the fiber gaps of the substrate layer; and curing the coating to form the artificial blood vessel. The basal layer of the artificial blood vessel is subjected to carboxylation modification before being coated, so that the hydrophilicity of the basal layer can be increased, and a coating solution can penetrate into fiber gaps of the basal layer to fill the fiber gaps of the basal layer when the basal layer is coated, so that the fracture caused by operations such as folding and suturing of the artificial blood vessel and the adverse event of postoperative blood leakage can be avoided when the basal layer is clinically used.

The artificial blood vessel and the preparation method thereof according to the present invention will be described in further detail with reference to the accompanying drawings. The advantages and features of the present invention will become more apparent from the following description. It is to be noted that the drawings are in a very simplified form and are not to precise scale, which is merely for the purpose of facilitating and distinctly claiming the embodiments of the present invention. Further, the structures illustrated in the drawings are often part of actual structures. In particular, the drawings may have different emphasis points and may sometimes be scaled differently.

As shown in fig. 1, the method for preparing an artificial blood vessel according to an embodiment of the present invention includes the following steps:

s11, providing a base layer;

s12, performing carboxylation modification on the base layer;

s13, coating the substrate layer after the carboxylation modification to form a coating layer, wherein the coating layer covers the surface of the substrate layer and fills the gap of the substrate layer;

s14, curing the coating to form the artificial blood vessel.

Wherein, the artificial blood vessel can be a straight tube type, a Y-shaped type, a side branch type, a three-branch type or a four-branch type; the material of the artificial blood vessel can be fiber material containing ester group, such as polyester, polyurethane or silk, or fiber material with carbon-hydrogen bond, such as polyester or polyacrylonitrile. In step S11, the base layer may be formed by weaving, knitting, braiding, or the like.

In one embodiment, the base layer is woven from a fiber material containing ester groups, and in step S12, the base layer is carboxylated by hydrolyzing the chemical bonds. Specifically, the chemical bond may be hydrolyzed by subjecting the base layer to a water bath treatment using an alkaline solution, and the ester group may be changed into a carboxyl group, which has hydrophilicity and may improve the hydrophilicity of the base layer. Wherein, the alkaline solution can adopt NaOH solution, the temperature of the water bath treatment can be 20-90 ℃, preferably, the temperature of the water bath treatment is 90 ℃, the time is 30-60 min, and the operation process can be specifically as follows: heating NaOH solution to 90 ℃, placing the basal layer in the NaOH solution, then carrying out water bath for 30-60 min at 90 ℃, then taking out and cleaning until the pH value is neutral, and drying.

In another embodiment, the substrate layer is woven from a fiber material containing carbon-hydrogen bonds, and the substrate layer is carboxylated in step S12 by grafting functional groups. Irradiating the substrate layer to generate carbon free radicals at carbon-hydrogen bonds of the substrate layer, and then immersing the substrate layer into an acrylic acid solution to combine carbon-carbon double bonds of acrylic acid with the carbon free radicals, so that carboxyl groups are grafted onto the substrate layer, and the hydrophilicity of the substrate layer is improved by utilizing the hydrophilicity of the carboxyl groups. Preferably, the substrate layer with the acrylic acid solution is irradiated again, and since the acrylic acid grafted on contains carbon-hydrogen bonds, carbon free radicals are generated at the carbon-hydrogen bonds irradiated, the acrylic acid which is not grafted on can be further grafted on, the grafting rate is further improved, and the hydrophilicity of the carboxylated substrate layer is further improved.

Preferably, the substrate layer is irradiated for the first time and irradiated for the second time under inert gas to prevent oxidation or other chemical reactions of the substrate layer, and the irradiation dose of the first irradiation is 50KGy, the irradiation dose of the second irradiation is 100KGy, and in addition, the concentration of the acrylic acid solution is preferably 30%. After grafting is finished, the base layer after carboxylation modification can be washed by using a magnesium hydroxide solution, and then washed by water and dried to remove excessive reaction products.

In step S13, the coating is a mixed solution composed of biodegradable polymers and a plasticizer, wherein the biodegradable polymers may be one or more of atelopeptide bovine collagen, atelopeptide porcine collagen, silk fibroin, gelatin, astragalus polysaccharide, albumin, polylactic acid, polyvinyl alcohol, degradable polyurethane, polycaprolactone, and copolymers thereof; the plasticizer can be one or more of polyethylene glycol, glycerol, Arabic gum, sorbitol, elastin, acetyl tributyl citrate and epoxidized oil, and the coating method can be realized by one or more of dipping, padding, air pressure spraying, piezoelectric spraying, vacuum coating, layer-by-layer self-assembly and pouring.

The coating step can be repeated for 2-16 times, and after each coating is finished, the coating is placed in an oven to be dried, and then the next coating is carried out.

In step S14, curing the coating may be achieved by one or more of physical crosslinking and chemical crosslinking; the chemical crosslinking can be realized by adopting one or more preparations of formaldehyde, glutaraldehyde, 1-ethyl carbodiimide hydrochloride, N-hydroxysuccinimide, genipin, catechin and sodium periodate; the physical crosslinking can be realized by one or more of thermal crosslinking and ultraviolet crosslinking.

Preferably, before the base layer after the carboxylation modification is coated, the base layer after the carboxylation modification is placed in a container, the container is vacuumized, and then the base layer after the carboxylation modification is coated. The surface of the substrate after carboxylation modification has a small amount of bubbles, and vacuumizing can play a defoaming role, so that coating is more uniform.

The following provides an exemplary description of the method for preparing the artificial blood vessel provided by the embodiment of the present invention.

Example 1

The straight tube type artificial blood vessel is prepared by a weaving method, the material of a basal layer is polyester fiber, the prepared basal layer of the artificial blood vessel is treated by water bath for 50 minutes at 90 ℃ in 1mol/L sodium hydroxide solution, and then the basal layer is taken out, washed to be neutral in PH and dried.

Preparing a biodegradable high polymer material, removing fat and fascia from fresh beef tendon, soaking for 48h at normal temperature by using 2mol/L hydrochloric acid, taking out, cleaning, adding 0.5mol/L sodium hydroxide solution for neutralization, and soaking in 0.1% pepsin at 20 ℃ for 12 h. Taking out, washing with water, cutting into 0.05-0.5 cm, soaking with hydrochloric acid under the same conditions, and performing enzymolysis once. And finally, grinding the small blocks into collagen with the diameter of 10-50 microns under the monitoring of a polarized light microscope, and drying at 50-90 ℃ to constant weight.

Preparing bovine collagen solution with the concentration of 0.5mg/mL and the toughening agent which is glycerol with the concentration of 0.1 mg/mL. Collagen was injected into the basal layer with a peristaltic pump for 15 minutes.

Taking out the basal layer, drying in a 50 ℃ oven, and repeatedly coating and drying for 6 times. Finally, the artificial blood vessel is placed in 2 percent glutaraldehyde solution for crosslinking, washed by water, dried and woven to form the straight tube type artificial blood vessel.

Example two

Preparing a double-branch (Y-shaped) artificial blood vessel by a weaving method, wherein a substrate layer is made of a fiber material containing carbon-hydrogen bonds, the substrate layer is placed in an irradiation chamber protected by nitrogen to be irradiated (irradiation dose is 50KGy), then the substrate layer is immersed in 30% acrylic acid solution, the liquid content of the substrate layer is 40% -60% (the liquid content of the substrate layer is the ratio of the total mass of the substrate layer with the immersion solution minus the dry weight to the dry weight) after being extruded by a compression roller, then the padded substrate layer is irradiated by electron beams under 100KGy, the grafting rate is 20%, after grafting, the substrate layer is cleaned by 10g/L magnesium hydroxide solution, and then the substrate layer is washed by water and dried.

Preparing gelatin solution with concentration of 2mg/mL, and polyethylene glycol as flexibilizer with concentration of 0.05 mg/mL. Uniformly coating the gelatin mixed solution on a basal layer by piezoelectric spraying for 5 minutes each time, taking out the basal layer after the spraying is finished, putting the basal layer in a 40-time oven for drying, and repeatedly coating and drying for 4 times. And finally, placing the double-branch artificial blood vessel in 1-2% formaldehyde solution for crosslinking, washing with water, drying, and finally weaving to form the double-branch (Y-shaped) artificial blood vessel.

Example three

The artificial blood vessel is prepared by a knitting method, wherein the material of a basal layer is polyester fiber, firstly, the basal layer is treated by 2mol/L sodium hydroxide solution in water bath at 80 ℃ for 50min, and then, the basal layer is taken out and cleaned to be neutral in PH and is dried and shaped.

The porcine collagen was prepared and a solution of porcine collagen was prepared at a concentration of 0.5mg/mL and the plasticizer was acetyl tributyl citrate at a concentration of 0.05mg/mL as in example one. In a closed container, the basal layer is pre-vacuumed, and then a collagen solution is flowed into the artificial blood vessel. And taking out the basal layer, and drying in an oven at 40-50 ℃. The coating was repeated 5 times and finally thermally crosslinked.

It should be noted that, several methods for preparing the artificial blood vessel are illustrated above, but it should be understood that in this embodiment, other methods mentioned in the foregoing part of this embodiment may also be adopted for preparing the substrate, coating the substrate, and curing the coating, so that corresponding contents of the above examples may be replaced to generate various schemes, and the present invention is not described again.

In addition, the embodiment of the present invention further provides an artificial blood vessel, where the artificial blood vessel includes a substrate layer and a coating layer, the coating layer covers a surface of the substrate layer and fills a gap of the substrate layer, and the artificial blood vessel can be prepared by the method for preparing the artificial blood vessel provided in this embodiment, that is, the substrate layer is first subjected to carboxylation modification, and then the coating layer is applied.

As shown in fig. 2, the carboxyl group can increase the hydrophilicity of the basal layer, so that a coating solution can penetrate into the interfiber spaces of the basal layer to fill the interfiber spaces of the basal layer when the basal layer is coated, so that the basal layer is not broken due to operations such as folding and suturing of an artificial blood vessel in clinical use, and further, the adverse event of postoperative blood leakage is avoided.

As can be seen from a comparison of Scanning Electron Microscope (SEM) images of the unmodified vascular prosthesis and the carboxylated vascular prosthesis, the unmodified vascular prosthesis coating forms a film only on the substrate surface, while the carboxylated vascular prosthesis coating penetrates into the internal crevices.

In conclusion, the artificial blood vessel and the preparation method thereof solve the problem that the coating solution is difficult to permeate into the gaps of the substrate layer when the artificial blood vessel is prepared.

The above description is only for the purpose of describing the preferred embodiments of the present invention, and is not intended to limit the scope of the present invention, and any variations and modifications made by those skilled in the art based on the above disclosure are within the scope of the appended claims.