CN116198138A

CN116198138A - Manufacturing method of silica gel blood vessel model containing hydrophobic texture inner surface

Info

Publication number: CN116198138A
Application number: CN202310182034.6A
Authority: CN
Inventors: 母立众; 何卫俊; 潘悦; 李建达; 王明亮; 迟青卓; 贺缨; 赵广
Original assignee: Dalian University of Technology
Current assignee: Dalian University of Technology
Priority date: 2023-03-01
Filing date: 2023-03-01
Publication date: 2023-06-02

Abstract

The invention belongs to the technical field of surgical medical simulation equipment, and provides a manufacturing method of a silica gel blood vessel model with a hydrophobic texture inner surface. The method is suitable for customizing different bionic microstructures or texture surfaces in a personalized way, can improve the blood compatibility of the artificial blood vessel, can better realize the uniformity and controllability of the thickness of the blood vessel, has high transparency, and can be used for simulating and observing the thrombosis condition.

Description

Manufacturing method of silica gel blood vessel model containing hydrophobic texture inner surface

Technical Field

The invention belongs to the technical field of surgical medical simulation equipment, and relates to a manufacturing method of a silica gel blood vessel with an inner surface hydrophobic texture.

Background

Since the early 20 th century, vascular anastomosis has been proposed, repair and replacement of blood vessels has been critical in the treatment of acute vascular injury and chronic atherosclerotic disease. Until now, vascular replacement and repair is a very common surgical procedure in the clinic, and the clinical need for engineering arterial substitutes is enormous. However, in many of these procedures, if whole body anticoagulation is not performed, thrombus is formed when fibrin and platelets in flowing blood adhere to the surface of these artificial materials, and these artificial blood vessels may be rapidly occluded due to thrombus formation. Thus, there is a need for the combined use of soluble anticoagulants, such as heparin, which greatly reduces the safety of the vascular prosthesis and hinders its effectiveness. Heparin causes morbidity and mortality through post-operative bleeding, thrombocytopenia, hypertriglyceridemia, hyperkalemia, and high sensitivity, heparin is disabled in some patient populations, and drug-related death due to most adverse clinical events is due to systemic anticoagulation. Thus, particularly for small caliber or low flow arterial bypass applications, there is a need for a suitable non-thrombogenic luminal surface that prevents blood clotting contact activation, platelet adhesion and activation, and thrombosis in the arterial system, while at the same time facing significant challenges such as immune acceptance, necessary tissue mechanics, low thrombosis, and immediate availability, making widespread clinical use of engineering arteries very difficult.

The blood compatibility of a biomaterial means that the surface of the biomaterial inhibits thrombosis and the effect of the biomaterial on blood physiological functions such as hemolysis of blood, reduced platelet function, temporary reduction of white blood cells, reduced function, complement activation, and the like. Implantable vascular prostheses save a myriad of lives and are occluded by thrombus formation from fibrin and platelets in flowing blood adhering to the surface of these artificial materials. Improving the blood compatibility of the surface of the material is a key element in the field of biological material research, and modifying the surface of the biological material is a key element in the link. The contact between the material and the living body is through the material surface and the living body contact each other, so it is very important to surface modify the material in order to obtain a material with good blood compatibility. The surface structure and composition, surface morphology, surface energy, hydrophilicity and hydrophobicity, chargeability and the like of the material can influence the interaction between the material and organisms, the surface characteristics of the material are changed through surface modification treatment, and the interaction between the material and blood can be changed. The hydrophobicity and free energy of the surface are closely related to adsorption, denaturation and the like of blood components, and the surface hydrophobicity of the material is improved by carrying out surface chemical treatment, surface physical modification and biological modification on the traditional material, so that the free energy of the surface is reduced to be close to the free energy value of the surface of an intima of a blood vessel, the blood compatibility of the material is improved, and the biomedical material capable of meeting the needs of people is researched and prepared.

The approach to improve the biocompatibility of materials, especially the blood compatibility, is mainly achieved by changing the surface properties of the materials, and changing the wettability of the surface of the materials is one of the effective approaches. In general, materials with both strongly hydrophobic and strongly hydrophilic surfaces have better hemocompatibility. When the hydrophobicity of the material surface is enhanced, the material has better blood compatibility due to the reduced adsorption capacity for blood components. In addition, the hydrophobicity and free energy of the material surface are closely related to adsorption, denaturation and the like of blood components. The surface free energy can be reduced by improving the hydrophobicity of the surface of the material, so that the surface free energy is reduced to a surface free energy value close to an intima of a blood vessel, and good antithrombotic performance can be obtained. The wettability of a material surface is determined by the chemical composition and the microscopic geometry of the surface. The acquisition of superhydrophobic surfaces is generally achieved by reducing the surface free energy and building a suitable roughness on the surface of the hydrophobic material. The chemical composition of the surface of a material determines its surface free energy and thus has an important influence on the wettability of the material. However, for a solid smooth surface, even with the lowest surface free energy surface, its contact angle with water can only reach about 110 degrees, and to achieve a high contact angle superhydrophobic surface, it must be considered to construct a suitable roughness structure on the surface of the hydrophobic material.

At present, the technical difficulty of preparing textures or microstructures on the inner side of an artificial blood vessel is high, and the problems of low efficiency and poor effect exist, so that a manufacturing method of a silica gel blood vessel containing a hydrophobic texture inner surface is introduced. The manufacturing method has relatively simple process, can be suitable for manufacturing small-caliber blood vessels and silica gel blood vessel models with different wall thicknesses, can personalized customize bionic microstructures on the inner side of the blood vessels, improves blood compatibility by re-engraving the silica gel blood vessels with hydrophobic texture inner surfaces, can be used for simulating and observing thrombus formation conditions of artificial blood vessels in experiments, and provides theoretical basis for clinical blood vessel replacement surgery treatment.

Patent application: an antithrombotic and tissue regeneration promoting three-layer bionic artificial blood vessel and a preparation method thereof are provided, with the application number of CN202210888742.7. The main problem is that the blood vessel inner layer of the three-layer bionic artificial blood vessel uses anticoagulant, which may generate side effects such as anticoagulant shedding or coagulation dysfunction.

Patent application: a preparation method of an electrostatic spinning artificial blood vessel with a micro-nano bionic intima structure, and application number CN201210287469.9. The artificial blood vessel prepared by the method has the microstructure of the intima orientation arrangement of the blood vessel, so that the blood compatibility of the artificial blood vessel meets the requirement of clinical anticoagulation performance, but the preparation method has high cost for preparing the artificial blood vessel, is complex to operate and has great difficulty in preparing the surfaces of different microstructures.

Patent application: a preparation device and a preparation method of an artificial blood vessel with a microstructure on the inner surface, and application number CN202210738869.0. The method has the main problems that the requirements on the size of the manufactured blood vessel are high, the manufacturing difficulty of the small-caliber blood vessel is high, the specific operation for manufacturing the column sheet with the microstructure is not detailed, and the manufacturing difficulty of the personalized microstructure is high.

Disclosure of Invention

The invention aims to solve the technical problem of providing a manufacturing method of a silica gel blood vessel with an inner surface texture or microstructure, which can manufacture a silica gel blood vessel model with an inner wall containing a hydrophobic texture and has certain universality for the individualized texture or microstructure blood vessel model. Solves the problem that the prior method needs special processing equipment or complex process. The whole manufacturing process of the method is simple, no special processing equipment is needed, and the applicability of the method is improved.

The technical scheme of the invention is as follows:

a method for preparing a silica gel vascular model with a hydrophobic texture inner surface is characterized in that the surfaces of animal feathers, plant leaves and the like in nature mostly have texture characteristics with different wettability. The disclosed experimental data show that the feathers of birds such as magpie feathers and swan feathers, plant leaves such as ginkgo leaves and lotus leaves, marine biological surfaces such as shark skin and shellfish textures have higher hydrophobicity, the patent mainly takes magpie feather textures as an example, a re-etching method is used for re-etching the hydrophobic feather textures on the surface of silica gel, and the re-etching method for using other texture surfaces is the same. And printing and manufacturing the soluble material-based mold by using a 3D printer, and configuring silica gel added with a certain proportion of curing agent. And filling silica gel in the mold, flatly adhering the feathers to a flat plate, covering the flat plate on the mold, heating the mold to solidify the silica gel after the silica gel is completely soaked in the feathers, dissolving the silica gel in water bath, and taking down the feathers to obtain the silica gel membrane containing the feather textures.

And printing and manufacturing the casting mold based on the soluble material by using a 3D printer, and carrying out surface smoothing treatment on the printed mold to remove the stepped problem caused by layer-by-layer printing. Embedding the textured surface of the silica gel film into a pouring container after wrapping the shaft column, slowly pouring silica gel from an inlet, enabling the silica gel to flow down along the seam of two side edges of the silica gel film, heating a mold to enable the silica gel to be solidified when the silica gel is not sinking, and dissolving the silica gel in water bath to obtain the silica gel vascular model with the inner surface texture.

For the blood vessel model production of the personalized microstructure, the personalized microstructure model needs to be obtained first, and then the microstructure is re-carved on the inner wall of the silica gel blood vessel by the method provided by the patent. The microstructure model can be manufactured through mechanical micromachining, soft lithography, photo-etching and other processes, and the prior art method is mature.

The method comprises the following specific steps:

step 1: cutting the cleaned magpie feathers into a regular shape, and fixing the back surfaces of the feathers on an acrylic plate;

step 2: printing a square container, a shaft column and a pouring container by using a 3D printer and using soluble printing consumables;

step 3: uniformly coating water or printing material dissolvent solution on the surface of the printing device for removing rough textures on the surface of the printing device, and drying after a plurality of times of coating to obtain the printing device with smooth surface;

step 4: preparing a double-component silica gel AB mixed solution, and mixing the double-component silica gel AB mixed solution with a curing agent according to a certain proportion to obtain a silica gel solution; and removing bubbles mixed by stirring by using a vacuum pump to obtain clear and transparent silica gel mixed liquid.

Step 5: pouring the silica gel mixed solution into a square container until overflow, pouring an acrylic plate adhered with feathers on the square container, and capping with a weight;

step 6: drying the integral model obtained in the step 5, after the silica gel is solidified, taking down the acrylic plate and the feathers, immersing the integral model in water, and obtaining a silica gel film containing the feathers after the square container is completely dissolved;

step 7: embedding the textured surface of the silica gel film into a pouring container after wrapping the shaft column, and slowly injecting the silica gel mixed solution from the inlet of the pouring container until the silica gel mixed solution at the inlet is not sinking;

step 8: and 5, integrally drying the silica gel blood vessel model obtained in the step 5, immersing the whole silica gel blood vessel model in water after the silica gel is solidified, and obtaining the silica gel blood vessel model containing the inner surface texture after the pouring container and the shaft column are completely dissolved.

In the step 1, magpie feathers can be replaced by feathers of other birds, plant leaves or marine surfaces.

In the step 2, the soluble printing consumables are: PVA (polyvinyl alcohol), water-soluble gypsum, HIPS (impact polystyrene) or ABS (acrylonitrile styrene butadiene styrene), wherein PVA is dissolved in water, HIPS is dissolved in limonene, ABS is dissolved in an organic solvent such as acetone.

In the step 3, the mass ratio of PVA to water in the printing material dissolvent solution is 1:10-1:5.

In the step 4, a two-component silica gel with a model number of 7055 is used according to A: b=1: preparing a double-component silica gel AB mixed solution according to the mass ratio of 1, and adding a vulcanizing agent accounting for 1% of the total mass of the double-component silica gel AB mixed solution to obtain a silica gel solution; and (3) uniformly stirring, and then placing the mixture into a vacuum machine for vacuumizing for 0.5-1 hour to obtain clear and transparent silica gel mixed solution.

In the step 6, the curing conditions are as follows: curing in a constant temperature oven at 60-90 deg.c for over 2 hr.

In the step 6, the dissolving process is as follows: and (3) placing the solidified integral model into a water tank until the square container is completely dissolved. In order to accelerate dissolution of the square container, hot water at 60-100 ℃ can be injected into the water tank, the hot water is replaced every 1-3 hours, the water temperature is controlled to be 60-100 ℃ by using a constant-temperature oven, and water replacement operation is carried out for 2-10 times until the square container is completely dissolved.

In the step 8, the curing conditions are as follows: curing in a constant temperature oven at 60-90 deg.c for over 6 hr.

In the step 8, the dissolving process is as follows: the solidified silica gel vascular model is put into a water tank, hot water at 60-100 ℃ is injected into the water tank, the hot water is replaced every 1-3 hours, a constant temperature oven is used for controlling the water temperature to be 60-100 ℃, dissolving operation is carried out, and 10-25 times of water replacing operation is carried out until the pouring container and the inner shaft column are completely dissolved.

The invention has the beneficial effects that:

(1) The method for manufacturing the silica gel blood vessel has low cost, simple process and repeatability;

(2) The method does not adopt anticoagulant, but only improves the blood compatibility of the silica gel blood vessel through the hydrophobicity of the surface microstructure;

(3) The method is suitable for customizing different bionic microstructures or texture surfaces in a personalized way, and can be used for manufacturing vascular models with different pipe diameters and wall thicknesses;

(4) The silica gel blood vessel model with the texture characteristic on the inner wall manufactured by the method can be used for simulating and observing the thrombosis condition of an artificial blood vessel by experiments, and provides a theoretical basis for clinical vascular replacement surgery treatment.

Drawings

Fig. 1 is a feather-bonded acrylic sheet.

Fig. 2 is a square container printed by a 3D printer using a soluble material PVA.

Figure 3 is a feathered silicone film.

Fig. 4 is a casting container and a peg printed with soluble material PVA by a 3D printer.

Fig. 5 is a mold with a textured silicone film wrapped around a pillow block.

FIG. 6 is a silica gel vascular model with feathered interior surfaces.

FIG. 7 is a schematic diagram of a mold with a textured silicone film wrapped around a mandrel.

In the figure, 1 is a casting container a;2 is a pouring container B;3 is a shaft post; 4 is a silica gel film with a repeated texture embedded in the die; and 5 is a pouring inlet.

Detailed Description

The invention is further illustrated by the following examples, which are not to be construed as limiting the invention, in conjunction with the accompanying drawings. Specific materials and sources thereof used in embodiments of the present invention are provided below. However, it should be understood that these are merely exemplary and are not intended to limit the present invention, as materials that are the same as or similar to the type, model, quality, nature, or function of the reagents and instruments described below may be used in the practice of the present invention. The experimental methods used in the following examples are conventional methods unless otherwise specified. Materials, reagents and the like used in the examples described below are commercially available unless otherwise specified.

Taking super-hydrophobic magpie feathers as an example, firstly cleaning the magpie feathers with clear water, airing at room temperature, and cutting the feathers into a regular shape with the width of 15mm and the length of 50 mm. The back of the feathers was stuck to a square acrylic plate 80mm long using double-sided tape as shown in FIG. 1.

The model was printed using a 3D printer, and the PVA container 1.5mm deep, 20mm wide and 50mm long was 3D printed as shown in fig. 2. And uniformly coating water on the surface of the printing device for removing rough textures on the surface of the printing device, and drying after 4 times of coating to obtain the printing device with a smooth surface. Model preparation a two-component silica gel with model number 7055 is used according to A: b=1: 1, preparing silica gel according to the mass ratio, adding a vulcanizing agent accounting for 1% of the total mass of the AB mixed solution, uniformly stirring, and then placing the mixture into a vacuum machine for vacuumizing for half an hour to obtain the silica gel mixed solution.

And pouring the silica gel mixed solution into a square container until overflowing, pouring an acrylic plate adhered with feathers on the square PVA container filled with the silica gel, capping with a heavy object, and placing in a constant-temperature drying box at 60 ℃ for curing for 2 hours. And after the silica gel is completely solidified, taking down the acrylic plate and the feathers, putting the silica gel film with the feather microstructure on the surface into a water tank, injecting hot water into the water tank, changing the hot water once every three hours, controlling the water temperature to be 60 ℃ by using a constant-temperature oven, performing dissolving operation, and performing 2 water changing operations after 6 hours, wherein the soluble PVA container is completely dissolved, thus obtaining the silica gel film with the feather texture, and the thickness of 1.5mm is shown in figure 3.

With a 3D printer, a post 70mm long and 5mm in diameter of PVA material and a casting container 8mm in inner diameter were printed out as shown in fig. 4. In the mass ratio of 1:10 and water are prepared into PVA aqueous solution, the PVA aqueous solution is uniformly coated on the surface of the model, and the surface of the whole model is smoother after four times of coating and drying. The surface of one side of the silica gel film with textures is wrapped by a shaft column and then is embedded into a pouring container, as shown in fig. 5, silica gel is slowly injected from an inlet until the silica gel at the inlet is no longer sinking, and the whole mold is placed into a constant temperature oven at 60 ℃ for curing for 6 hours.

Placing the PVA pouring container model after silica gel solidification into a water tank, injecting hot water into the water tank, changing the hot water once every three hours, controlling the water temperature to be 60 ℃ by using a constant-temperature oven, performing dissolution operation, and completely dissolving the soluble container and an inner shaft column after 48 hours and 16 water changing operations, thereby obtaining the silica gel blood vessel model with feather textures, as shown in figure 6.

Compared with the existing artificial silica gel blood vessel, the preparation process is very simple, the lazy nature of processing equipment is low, and the personalized customization of the inner surface microstructure and the manufacturing of the blood vessel model with controllable thickness can be realized.

The description of the exemplary embodiments presented above is merely illustrative of the technical solution of the present invention and is not intended to be exhaustive or to limit the invention to the precise form described. It is evident that many alternatives and variations are possible to those of ordinary skill in the art in light of the foregoing examples. The exemplary embodiments were chosen and described in order to explain the specific principles of the invention and its practical application to thereby enable others skilled in the art to understand, make and utilize the invention in various exemplary embodiments and with various alternatives and modifications. It is intended that the scope of the invention be defined by the following claims and their equivalents.

Claims

1. A method for manufacturing a silica gel blood vessel model containing a hydrophobic texture inner surface is characterized by comprising the following specific steps:

step 4: preparing a double-component silica gel AB mixed solution, and mixing the double-component silica gel AB mixed solution with a curing agent according to a certain proportion to obtain a silica gel solution; removing bubbles mixed by stirring by using a vacuum pump to obtain clear and transparent silica gel mixed liquid;

2. The method according to claim 1, wherein in step 1, the magpie feathers are replaced by feathers of other birds, plant leaves or marine organisms.

3. The method for manufacturing a silicone vascular model with a hydrophobic texture inner surface according to claim 1, wherein in the step 2, the dissolvable printing consumables are: PVA, water soluble gypsum, HIPS, or ABS.

4. The method for manufacturing a silica gel vascular model with a hydrophobic texture inner surface according to claim 1, wherein in the step 3, the mass ratio of PVA to water in the printing material dissolver solution is 1:10-1:5.

5. The method of claim 1, wherein in step 4, a two-component silica gel of type 7055 is used according to a: b=1: preparing a double-component silica gel AB mixed solution according to the mass ratio of 1, and adding a vulcanizing agent accounting for 1% of the total mass of the double-component silica gel AB mixed solution to obtain a silica gel solution; and (3) uniformly stirring, and then placing the mixture into a vacuum machine for vacuumizing for 0.5-1 hour to obtain clear and transparent silica gel mixed solution.

6. The method for preparing a silica gel vascular model with a hydrophobic texture inner surface according to claim 1, wherein in the step 6, the curing conditions are as follows: curing in a constant temperature oven at 60-90 deg.c for over 2 hr.

7. The method for preparing a silica gel vascular model with a hydrophobic texture inner surface according to claim 1, wherein in the step 6, the dissolution process is as follows: placing the solidified integral model into a water tank until the square container is completely dissolved; in order to accelerate dissolution of the square container, hot water at 60-100 ℃ can be injected into the water tank, the hot water is replaced every 1-3 hours, the water temperature is controlled to be 60-100 ℃ by using a constant-temperature oven, and water replacement operation is carried out for 2-10 times until the square container is completely dissolved.

8. The method for preparing a silica gel vascular model with a hydrophobic texture inner surface according to claim 1, wherein in the step 8, the curing conditions are as follows: curing in a constant temperature oven at 60-90 deg.c for over 6 hr.

9. The method for preparing a silica gel vascular model with a hydrophobic texture inner surface according to claim 1, wherein in the step 8, the dissolution process is as follows: the solidified silica gel vascular model is put into a water tank, hot water at 60-100 ℃ is injected into the water tank, the hot water is replaced every 1-3 hours, a constant temperature oven is used for controlling the water temperature to be 60-100 ℃, dissolving operation is carried out, and 10-25 times of water replacing operation is carried out until the pouring container and the inner shaft column are completely dissolved.