Layered medical patch and its preparation method and application

Abstract

The present invention relates to a layered medical patch and a preparation method and application thereof. The layered medical patch comprises a base layer, a strong adhesion material layer and an anti-adhesion material layer; the strong adhesion material layer and the anti-adhesion material layer are respectively arranged on the front and back sides of the base layer; wherein the anti-adhesion material layer is a polyethylene glycol material. The patch has the advantages of both adhesive materials and medical patches, and has the strong adhesion performance of adhesives and the low friction performance of anti-adhesion materials. The preparation method is easy to operate and has low cost. The layered medical patch prepared by the present invention has the advantages of simple operation, can effectively shorten the operation time, relieve the pain of patients, and effectively reduce the occurrence of adhesion and reduce secondary damage in actual surgery.

Description

Technical Field

[0001] The present invention relates to the field of biomedical materials, and more specifically to a layered medical patch and a preparation method and application thereof. Background Art

[0002] With the continuous development of medicine and biomaterials, medical patches are widely used in repairing defects in human body parts, such as hernia repair, chest wall reconstruction, pericardial repair, female pelvic floor reconstruction, kidney fixation and dura mater repair. Medical patches have good toughness and biological inertness, and can act as cell scaffolds during tissue repair, providing mechanical support for tissues and organs. However, during the use of a single patch, there are problems such as chronic pain and infection adhesion caused by patch shrinkage. At the same time, traditional patches must be fixed by traditional methods such as sutures, staples or spiral staples that penetrate tissues. The process is time-consuming and cannot achieve rapid closure of the wound.

[0003] The other side of the existing medical patch, which is in contact with healthy tissue, is prone to adhesion with surrounding tissues, further promoting the continuous proliferation of scar tissue and causing serious complications. Therefore, it is necessary to construct an ultra-smooth and anti-friction surface to achieve the ideal state that is difficult to achieve with a single patch, thereby ensuring good tissue growth during the repair process and effectively reducing the occurrence of adhesion. Therefore, it is urgent to give traditional medical patches new composite functions and construct new composite medical patches with surface adhesion and infiltration. Summary of the invention

[0004] In view of the problems that traditional patches must be sutured and cause inflammatory adhesions when treating and repairing tissue damage, one of the purposes of the present invention is to provide a layered medical patch that effectively promotes the repair of damaged tissue while avoiding traditional fixation methods such as sutures, staples or spiral staples, and effectively reduces the occurrence of adhesions and reduces complications such as postoperative nerve damage.

[0005] To achieve the above purpose, the technical solution adopted by the present invention is as follows:

[0006] A layered medical patch comprises a base layer, a strong adhesion material layer and an anti-adhesion material layer, wherein the strong adhesion material layer and the anti-adhesion material layer are respectively arranged on the front and back sides of the base layer; wherein the anti-adhesion material layer is a polyethylene glycol material. The layered medical patch of the present application uses a medical strong adhesion material on the side that is in direct contact with the damaged tissue, and uses adhesion instead of needle and thread suturing, which has the advantages of simple operation, non-invasive adhesion, instant sealing and hemostasis, and is in direct contact with the damaged tissue, accelerating wound healing and reducing pain. The side of the patch that is in contact with the healthy tissue uses an anti-adhesion material, whose excellent properties of smoothness and low friction can effectively prevent adhesion effects and reduce complications.

[0007] In the above technical solution, the thickness of the strong adhesion material layer is 10-100 μm, preferably 20-50 μm.

[0008] In the above technical solution, the thickness of the anti-adhesion material layer is 100-400 μm, preferably 200-300 μm.

[0009] In the above technical solution, the anti-adhesion material layer is a polymer material based on multi-arm polyethylene glycol; preferably three-arm polyethylene glycol and / or four-arm polyethylene glycol.

[0010] In the above technical solution, the material of the patch base layer can be selected from various medical polymer materials commonly used in medical patches in the prior art, preferably including at least one of polypropylene and polytetrafluoroethylene.

[0011] In the above technical solution, the patch base layer is a textile of the medical polymer, and its longitudinal density is 20 to 100 rows / 5 cm, and its transverse density is 10 to 70 wales / 5 cm; preferably, its longitudinal density is 60 to 90 rows / 5 cm, and its transverse density is 30 to 5 wales / 5 cm. The number of coils within a specified area of ​​a knitted fabric is usually expressed as PA×PB. Among them, the transverse density PA is expressed by the number of wales of coils within a specified length along the row direction of the knitted fabric coils. The longitudinal density PB is expressed by the number of rows of coils within a specified length along the wale direction of the knitted fabric coils.

[0012] In the above technical solution, the strong adhesion material layer is at least one of polydopamine adhesive materials, cyanoacrylate adhesive materials, polyurethane adhesive materials, chitosan adhesive materials and gelatin adhesive materials; preferably, it is a polydopamine adhesive material.

[0013] The second object of the present invention is to provide a method for preparing the layered medical patch, which is simple to operate, low in cost, high in precision and highly repeatable. The spin coating method is used to give the traditional medical patch a new composite function, thereby constructing a new layered medical patch with surface adhesion and wettability.

[0014] To achieve the above purpose, the technical solution adopted by the present invention is as follows:

[0015] A method for preparing a layered medical patch comprises: first preparing a patch base layer, then preparing a strong adhesion material spin coating solution and an anti-adhesion material spin coating solution respectively, and then spin coating the strong adhesion material spin coating solution and the anti-adhesion material spin coating solution respectively onto the front and back sides of the base layer to obtain the layered medical patch.

[0016] Preferably, the preparation method further comprises drying the product for 6-12 hours and then transferring it to a freeze dryer for 12-18 hours. Freeze drying can further remove residual organic molecules without destroying the material structure.

[0017] In the above technical solution, the preparation method of the patch base layer can be carried out by a common preparation method in the prior art. For example, it can be obtained by spinning polymer fibers. The present invention preferably prepares the patch base layer by the following steps:

[0018] Medical polymers (such as polypropylene and / or polytetrafluoroethylene) are melt-spun and then heat-treated under a stretched state to form polymer monofilaments. The process flow is: medical polymer slices - melt spinning machine extrusion spinning - cold water bath cooling - hot water bath drawing - hot air drawing - air heat setting - winding. After that, the medical polymer monofilaments are spun to prepare the patch base layer.

[0019] The polymer monofilament spinning can adopt the spinning process and conditions commonly used in the prior art.

[0020] A preferred method for spinning medical polymer monofilaments may include: controlling the spinning temperature between 270-285°C, the melt enters the cooling water tank through the spinning assembly, the water tank temperature is controlled at about 30°C, the first-stage hot water drawing temperature is controlled between 85-95°C, and the second-stage hot air drawing temperature is controlled between 140-160°C. Specifically, the number of spinneret holes is 100-200, the spinneret hole diameter is between 0.5-1mm, the winding rate is 140m / min, the heat setting temperature is 100°C, the main machine pressure is 5-10MPa, the metering pump pressure is 2-3MPa, the screw speed is 20-30rpm, and the metering pump speed is 5-10rpm.

[0021] In the above technical solution, the preparation of the spin coating solution of the strong adhesion material includes: dissolving the strong adhesion material, adding periodate, adjusting the pH to 7-8 and letting it stand.

[0022] Preferably, the strong adhesion material is dissolved in an acidic buffered saline solution, preferably a phosphate buffered saline solution; then periodate is added, preferably at least one of sodium periodate or potassium periodate; and the pH is adjusted to 7-8 and allowed to stand for 6-12 hours, preferably 7; an alkaline solution is used to adjust the pH, preferably sodium hydroxide or potassium hydroxide.

[0023] In the above technical solution, the preparation of the anti-adhesion material spin coating solution includes: first preparing the anti-adhesion material, and then dissolving the material. Preferably, the dissolution is performed in an acidic buffered saline solution, and the acidic buffered saline solution is further preferably a phosphate buffered saline solution.

[0024] In the above technical solution, the strong adhesion material in the spin coating solution is dissolved in an acidic buffer salt solution until dissolved, and the mass percentage concentration is preferably 2-10%, more preferably 5-10%.

[0025] The anti-adhesion material in the spin coating solution is dissolved in the acidic buffered saline solution until dissolved, and the mass percentage concentration is preferably 1-20%, and more preferably 10-15%. If the concentration is too low, the prepared layered medical patch has low adhesion and cannot achieve the repair effect. On the contrary, if the concentration is too high, the adhesion material is easy to agglomerate on the surface of the polymer substrate and cannot be evenly dispersed. Therefore, a suitable concentration is required. The acidic buffered saline solution can adopt the acidic buffered saline solution commonly used in the prior art. The present invention preferably adopts a phosphate buffered saline solution, and its concentration is generally 5 to 10 mmol L -1 .

[0026] In the above technical solution, the amount of the strong adhesion material spin coating solution spin coated on the base layer is 2-50 μL / cm 2 , preferably 20-30 μL / cm 2 .

[0027] Preferably, the amount of the anti-adhesion material spin coating solution spin coated on the substrate layer is 1-100 μL / cm 2 , preferably 50-80 μL / cm 2 .

[0028] In the above technical solution, the spin coating includes a first step of spin coating and a second step of spin coating, the first step of spin coating has a rotation speed between 500-2000r, preferably 1000-1500r; the second step of spin coating has a rotation speed between 2000-10000r, preferably 6000-8000r; and / or,

[0029] The first step spin coating time is between 10-120 s, preferably between 60-90 s; the second step spin coating time is between 30-300 s, preferably between 120-180 s.

[0030] The preparation of the patch of the present invention requires two spin coatings, one on each side of the patch substrate. One side is spin coated with a strong adhesion material, and the other side is spin coated with an anti-adhesion material. Each spin coating adopts two steps of spin coating at different rotation speeds because the first step of low-speed spin coating can evenly spread the adhesive material, which is more conducive to further dispersion; because if the high-speed spin coating is directly performed, the strong adhesion material is easy to be unevenly dispersed.

[0031] The third object of the present invention is to provide the application of the above-mentioned layer structure medical patch in surgical repair materials.

[0032] Beneficial effects of the present invention:

[0033] 1) The layered medical patch prepared by the present invention based on the two-step spin coating method has both the strong adhesion performance of the adhesive and the low friction performance of the anti-adhesion material. The preparation method is simple to operate and low in cost.

[0034] 2) The layered medical patch prepared by the present invention has the advantages of simple operation, effective shortening of operation time, relief of patient pain, effective reduction of adhesion occurrence, and reduction of secondary injury in actual surgery. DETAILED DESCRIPTION

[0035] The present invention is described in detail below in conjunction with specific embodiments. It is necessary to point out that the following embodiments are only used to further illustrate the present invention and cannot be understood as limiting the scope of protection of the present invention. Some non-essential improvements and adjustments made to the present invention by those skilled in the art based on the contents of the present invention still fall within the scope of protection of the present invention.

[0036] It should also be noted that the various specific technical features described in the following specific embodiments can be combined in any suitable manner without contradiction. To avoid unnecessary repetition, the present invention will not further describe various possible combinations.

[0037] In addition, the various embodiments of the present invention may be arbitrarily combined as long as they do not violate the concept of the present invention. The technical solutions thus formed belong to part of the original disclosure of this specification and also fall within the protection scope of the present invention.

[0038] Source of reagents: All reagents are commercially available.

[0039] Example 1

[0040] Preparation of the patch base layer: The medical polypropylene monofilament (diameter 0.15mm) is produced by melt spinning and then heat treated under stretching. The process flow is: medical polypropylene slices - melt spinning machine extrusion spinning - cold water bath cooling - hot water bath drawing - hot air drawing - air heat setting - winding. Then the polypropylene monofilament is spun to prepare the patch base layer. Spinning process: The spinning temperature is controlled between 270-285℃, the melt passes through the spinning assembly and enters the cooling water tank, the water tank temperature is controlled at about 30℃, the first-level hot water stretching temperature is controlled between 85-95℃, and the second-level hot air stretching temperature is controlled between 140-160℃. Specifically, the number of spinneret holes is 100-200, the spinneret hole diameter is between 0.5-1mm, the winding speed is 140m / min, the heat setting temperature is 100℃, the main machine pressure is 5-10MPa, the metering pump pressure is 2-3MPa, the screw speed is 20-30rpm, and the metering pump speed is 5-10rpm. The vertical density of the base layer of the obtained patch is 50 horizontal rows / 5cm, and the horizontal density is 33 vertical rows / 5cm. All experimental materials are tested according to the national standard GB / T 6529 under standard atmospheric conditions (temperature 20±2.0℃, humidity 65±4% after humidity adjustment).

[0041] Preparation of strong adhesion material layer: 40 mg of 6-hydroxydopamine hydrochloride was dissolved in 1 g of 10 mmol L -1 10 mg sodium periodate NaIO4 was added to the phosphate buffered saline solution, and 40 mmol L -1 Adjust the pH to 7.0 with sodium hydroxide NaOH and let it stand. Use a pipette to accurately measure 100 μL of the solution and transfer it to the polymer substrate. The spin coater is set to spin coat at a low speed of 500 rpm for 30 seconds to obtain a uniformly dispersed solution, and then increase the speed to 6000 rpm for 60 seconds. Transfer the resulting layered patch to a vacuum drying oven, keep it for 12 hours, and then transfer it to a freeze dryer and let it stand for 12 hours.

[0042] Preparation of anti-adhesion material layer: First, prepare a multi-arm polyethylene glycol acrylate soluble precursor. Take 50 nml of polyethylene glycol and add 100 ml of dichloromethane until the solution is clear, then add equal amounts of triethylamine and acryloyl chloride, and wrap the reactor with tin foil to avoid light. After reacting for 24 hours, filter the reaction mixture through a neutral aluminum bed paved with aluminum oxide powder and rinse with a large amount of dichloromethane. Add sodium bicarbonate powder to the clarified filtrate and stir for one hour, filter to remove sodium bicarbonate, and rotary evaporate the filtrate to concentrate it to remove most of the dichloromethane, then add a large amount of anhydrous ether to precipitate, filter, and obtain a multi-arm polyethylene glycol acrylate white powder.

[0043] Weigh 40 mg of multi-arm polyethylene glycol acrylate and dissolve it in 1 g of 10 mmol L -1 phosphate buffered saline solution. Use a pipette to accurately measure 100 μL of the solution and transfer it to the polymer substrate on which the strong adhesive material is spin-coated. The spin coater is set to spin-coat at a low speed of 500 rpm for 30 seconds to obtain a uniformly dispersed solution, and then increase the speed to 6000 rpm for 60 seconds. The resulting layered patch is transferred to a vacuum drying oven, kept for 12 hours to dry, and then further transferred to a freeze dryer for 12 hours. The thickness of the adhesion layer is 50 μm, and the thickness of the anti-adhesion layer is 200 μm.

[0044] Example 2

[0045] The polypropylene patch base layer was prepared by the method mentioned in Example 1.

[0046] Preparation of strong adhesion material layer: weigh 50 mg of 6-hydroxydopamine hydrochloride and dissolve it in 1 g of 10 mmol / L -1 10 mg sodium periodate NaIO4 was added to the phosphate buffered saline solution, and 40 mmol L -1Adjust the pH to 7.0 with sodium hydroxide NaOH and let it stand. Use a pipette to accurately measure 100 μL of the solution and transfer it to the polymer substrate. The spin coater is set to spin coat at a low speed of 500 rpm for 30 seconds to obtain a uniformly dispersed solution, and then increase the speed to 6000 rpm for 60 seconds. Transfer the resulting layered patch to a vacuum drying oven, keep it for 12 hours, and then transfer it to a freeze dryer and let it stand for 12 hours.

[0047] Preparation of anti-adhesion material layer: Weigh 50 mg of multi-arm polyethylene glycol acrylate and dissolve it in 1 g of 10 mmol L -1 phosphate buffered saline solution. Use a pipette to accurately measure 100 μL of the solution and transfer it to the polymer substrate on which the strong adhesive material is spin-coated. The spin coater is set to spin-coat at a low speed of 500 rpm for 30 seconds to obtain a uniformly dispersed solution, and then increase the speed to 6000 rpm for 60 seconds. The resulting layered patch is transferred to a vacuum drying oven, kept for 12 hours to dry, and then further transferred to a freeze dryer for 12 hours. The thickness of the adhesion layer is 80 μm, and the thickness of the anti-adhesion layer is 180 μm.

[0048] Example 3

[0049] The polypropylene patch base layer was prepared by the method mentioned in Example 1.

[0050] Preparation of strong adhesion material layer: weigh 50 mg of 6-hydroxydopamine hydrochloride and dissolve it in 1 g of 10 mmol / L -1 10 mg sodium periodate NaIO4 was added to the phosphate buffered saline solution, and 40 mmol L -1 Adjust the pH to 7.0 with sodium hydroxide NaOH and let it stand. Use a pipette to accurately measure 100 μL of the solution and transfer it to the polymer substrate. The spin coater is set to spin coat at a low speed of 500 rpm for 30 seconds to obtain a uniformly dispersed solution, and then increase the speed to 8000 rpm for 60 seconds. Transfer the resulting layered patch to a vacuum drying oven, keep it for 12 hours to dry, and then transfer it to a freeze dryer and let it stand for 12 hours.

[0051] Preparation of anti-adhesion material layer: Weigh 50 mg of multi-arm polyethylene glycol acrylate and dissolve it in 1 g of 10 mmol L -1 phosphate buffered saline solution. Use a pipette to accurately measure 100 μL of the solution and transfer it to the polymer substrate on which the strong adhesive material is spin-coated. The spin coater is set to spin-coat at a low speed of 500 rpm for 30 seconds to obtain a uniformly dispersed solution, and then increase the speed to 8000 rpm for 60 seconds. The resulting layered patch is transferred to a vacuum drying oven, kept for 12 hours to dry, and then further transferred to a freeze dryer for 12 hours. The thickness of the adhesion layer is 40 μm, and the thickness of the anti-adhesion layer is 240 μm.

[0052] Example 4

[0053] Preparation of the patch base layer: The medical polytetrafluoroethylene monofilament (diameter 0.15mm) was produced by melt spinning and then heat treated under stretching. The process flow is: medical polypropylene slices - melt spinning machine extrusion spinning - cold water bath cooling - hot water bath drawing - hot air drawing - air heat setting - winding. The conditions are similar to those of the polypropylene monofilament spinning process. The spinning temperature is controlled between 270-285℃. The melt enters the cooling water tank through the spinning assembly. The water tank temperature is controlled at about 30℃. The first-level hot water drawing temperature is controlled between 85-95℃, and the second-level hot air drawing temperature is controlled between 140-160℃. The vertical density of the obtained patch base layer is 50 horizontal rows / 5cm, and the horizontal density is 33 vertical rows / 5cm. All experimental materials are tested according to the national standard GB / T 6529 under standard atmospheric conditions (temperature 20±2.0℃, humidity 65±4% after humidity adjustment).

[0054] Preparation of strong adhesion material layer: Weigh 40 mg of 6-hydroxydopamine hydrochloride and dissolve it in 1 g of 10 mmol / L -1 10 mg sodium periodate NaIO4 was added to the phosphate buffered saline solution, and 40 mmol L -1 Adjust the pH to 7.0 with sodium hydroxide NaOH and let it stand. Use a pipette to accurately measure 100 μL of the solution and transfer it to the polymer substrate. The spin coater is set to spin coat at a low speed of 500 rpm for 30 seconds to obtain a uniformly dispersed solution, and then increase the speed to 6000 rpm for 60 seconds. Transfer the resulting layered patch to a vacuum drying oven, keep it for 12 hours, and then transfer it to a freeze dryer and let it stand for 12 hours.

[0055] Preparation of anti-adhesion material layer: Weigh 40 mg of multi-arm polyethylene glycol acrylate and dissolve it in 1 g of 10 mmol L -1 phosphate buffered saline solution. Use a pipette to accurately measure 100 μL of the solution and transfer it to the polymer substrate on which the strong adhesive material is spin-coated. The spin coater is set to spin-coat at a low speed of 500 rpm for 30 seconds to obtain a uniformly dispersed solution, and then increase the speed to 6000 rpm for 60 seconds. The resulting layered patch is transferred to a vacuum drying oven, kept for 12 hours to dry, and then further transferred to a freeze dryer for 12 hours. The thickness of the adhesion layer is 45 μm, and the thickness of the anti-adhesion layer is 190 μm.

[0056] Example 5

[0057] The method mentioned in Example 4 was used to prepare the polytetrafluoroethylene patch base layer.

[0058] Preparation of strong adhesion material layer: weigh 50 mg of 6-hydroxydopamine hydrochloride and dissolve it in 1 g of 10 mmol / L -1 10 mg sodium periodate NaIO4 was added to the phosphate buffered saline solution, and 40 mmol L -1 Adjust the pH to 7.0 with sodium hydroxide NaOH and let it stand. Use a pipette to accurately measure 100 μL of the solution and transfer it to the polymer substrate. The spin coater is set to spin coat at a low speed of 500 rpm for 30 seconds to obtain a uniformly dispersed solution, and then increase the speed to 6000 rpm for 60 seconds. Transfer the resulting layered patch to a vacuum drying oven, keep it for 12 hours, and then transfer it to a freeze dryer and let it stand for 12 hours.

[0059] Preparation of anti-adhesion material layer: Weigh 50 mg of multi-arm polyethylene glycol acrylate and dissolve it in 1 g of 10 mmol L -1 phosphate buffered saline solution. Use a pipette to accurately measure 100 μL of the solution and transfer it to the polymer substrate on which the strong adhesive material is spin-coated. The spin coater is set to spin-coat at a low speed of 500 rpm for 30 seconds to obtain a uniformly dispersed solution, and then increase the speed to 6000 rpm for 60 seconds. The resulting layered patch is transferred to a vacuum drying oven, kept for 12 hours to dry, and then further transferred to a freeze dryer for 12 hours. The thickness of the adhesion layer is 70 μm, and the thickness of the anti-adhesion layer is 185 μm.

[0060] Example 6

[0061] The method mentioned in Example 4 was used to prepare the polytetrafluoroethylene patch base layer.

[0062] Preparation of strong adhesion material layer: weigh 50 mg of 6-hydroxydopamine hydrochloride and dissolve it in 1 g of 10 mmol / L -1 10 mg sodium periodate NaIO4 was added to the phosphate buffered saline solution, and 40 mmol L -1 Adjust the pH to 7.0 with sodium hydroxide NaOH and let it stand. Use a pipette to accurately measure 100 μL of the solution and transfer it to the polymer substrate. The spin coater is set to spin coat at a low speed of 500 rpm for 30 seconds to obtain a uniformly dispersed solution, and then increase the speed to 8000 rpm for 60 seconds. Transfer the resulting layered patch to a vacuum drying oven, keep it for 12 hours to dry, and then transfer it to a freeze dryer and let it stand for 12 hours.

[0063] Preparation of anti-adhesion material layer: Weigh 50 mg of multi-arm polyethylene glycol acrylate and dissolve it in 1 g of 10 mmol L -1phosphate buffered saline solution. Use a pipette to accurately measure 100 μL of the solution and transfer it to the polymer substrate on which the strong adhesive material is spin-coated. The spin coater is set to spin-coat at a low speed of 500 rpm for 30 seconds to obtain a uniformly dispersed solution, and then increase the speed to 8000 rpm for 60 seconds. The resulting layered patch is transferred to a vacuum drying oven, kept for 12 hours to dry, and then further transferred to a freeze dryer for 12 hours. The thickness of the adhesion layer is 45 μm, and the thickness of the anti-adhesion layer is 220 μm.

[0064] Test Case

[0065] The above examples were subjected to viscosity test and mechanical property test, and the results are shown in the following table.

[0066] The adhesion test method is to use weights to adhere to the fixed area size patches (select 5cm 2 ) are suspended for testing on both sides (one side with strong adhesion material and one side with anti-adhesion material), with the adhesion time being greater than 60s as the standard, and the weight of the weight is recorded to detect the stickiness.

[0067] The mechanical test method is to use a fabric strength tester, refer to GB / T 3923.1-1997. The sample size is 250mm*50mm, the pre-tension is 2N, the clamping distance of the longitudinal sample is 200mm, the clamping distance of the transverse sample is 100mm, the tensile speed is 100mm / min, and the longitudinal and transverse tests are performed 10 times each.

[0068] Table 1: Performance indicators of the examples

[0069]

[0070] Table 1 shows that a new type of layered medical patch with surface adhesion and wettability was successfully prepared. The patch can directly adhere to the wound on the side in contact with the damaged tissue, avoiding the need for needle and thread suture to reduce pain; the patch has a smooth anti-adhesion surface on the side in contact with the healthy tissue, solving the problem of serious adhesion effect of existing patches.

[0071] Comparative Example

[0072] The polypropylene substrate was prepared by the method mentioned in Example 1.

[0073] Weigh 40 mg of 6-hydroxydopamine hydrochloride and dissolve it in 1 g of 10 mmol L -1 10 mg sodium periodate NaIO4 was added to the phosphate buffered saline solution, and 40 mmol L -1Adjust the pH to 7.0 with sodium hydroxide NaOH and let it stand. Use a pipette to accurately measure 100 μL of the solution and transfer it to the polymer substrate. The spin coater is set to spin coat at a low speed of 500 rpm for 30 seconds to obtain a uniformly dispersed solution, and then increase the speed to 6000 rpm for 60 seconds. Transfer the resulting patch to a vacuum drying oven, keep it for 12 hours to dry, and then transfer it to a freeze dryer and let it stand for 12 hours.

[0074] The patch prepared by this method only has an adhesive layer, and has a serious adhesion effect after being implanted in the body. However, the patch material used in the embodiment of the present invention has a smooth and moist surface on the side in contact with the healthy tissue, which can effectively prevent adhesion.

[0075] The present invention has been described in detail above in conjunction with specific implementations and exemplary examples, but these descriptions cannot be understood as limiting the present invention. Those skilled in the art understand that, without departing from the spirit and scope of the present invention, a variety of equivalent substitutions, modifications or improvements may be made to the technical solution of the present invention and its implementation methods, all of which fall within the scope of the present invention. The scope of protection of the present invention shall be subject to the attached claims.

Claims

1. A layered medical patch, comprising a base layer, a strong adhesion material layer and an anti-adhesion material layer, wherein the strong adhesion material layer and the anti-adhesion material layer are respectively arranged on the front and back sides of the base layer; wherein: The anti-adhesion material layer is multi-arm polyethylene glycol acrylate; the material of the base layer is selected from medical polymer textiles, the longitudinal density is 20-100 horizontal rows / 5 cm, and the transverse density is 10-70 vertical rows / 5 cm; the medical polymer is selected from at least one of polypropylene and polytetrafluoroethylene; the strong adhesion material layer is a polydopamine adhesive material; The preparation method of the medical patch comprises: first preparing a patch base layer, then preparing a strong adhesion material spin coating solution and an anti-adhesion material spin coating solution respectively, then transferring the strong adhesion material spin coating solution and the anti-adhesion material spin coating solution to the front and back sides of the base layer respectively, and then spin coating the front and back sides of the base layer to obtain the layer structure medical patch; The mass percentage concentration of the strong adhesion material in the spin coating solution of the strong adhesion material is 2-10%; the mass percentage concentration of the anti-adhesion material in the spin coating solution of the anti-adhesion material is 1-20%; The spin coating comprises a first step of spin coating and a second step of spin coating, wherein the first step of spin coating has a rotation speed between 500-2000 rpm; and the second step of spin coating has a rotation speed between 2000-10000 rpm.

2. The medical patch according to claim 1, characterized in that: The strong adhesion material layer has a thickness of 10-100 μm; and / or, The anti-adhesion material layer has a thickness of 100-400 μm; and / or, The thickness of the base layer is 1-10 mm.

3. The medical patch according to claim 2, characterized in that: The strong adhesion material layer has a thickness of 20-50 μm; and / or, The anti-adhesion material layer has a thickness of 200-300 μm; and / or, The thickness of the base layer is 2-5 mm.

4. The medical patch according to claim 1, characterized in that: The multi-arm polyethylene glycol acrylate is three-arm polyethylene glycol acrylate and / or four-arm polyethylene glycol acrylate.

5. A method for preparing the medical patch according to any one of claims 1 to 4, comprising: First, prepare the patch base layer, then prepare a strong adhesion material spin coating solution and an anti-adhesion material spin coating solution respectively, then transfer the strong adhesion material spin coating solution and the anti-adhesion material spin coating solution to the front and back sides of the base layer respectively, and then spin coat them to the front and back sides of the base layer to obtain the layered medical patch.

6. The preparation method according to claim 5, characterized in that: The mass percentage concentration of the strong adhesion material in the strong adhesion material spin coating solution is 5-10%; and / or the mass percentage concentration of the anti-adhesion material in the anti-adhesion material spin coating solution is 10-15%.

7. The preparation method according to claim 5, characterized in that: The amount of the strong adhesion material spin coating solution spin coated on the substrate layer is 2-50 μL / cm 2 ; and / or, the amount of the anti-adhesion material spin coating solution spin coated on the substrate layer is 1-100 μL / cm 2 .

8. The preparation method according to claim 7, characterized in that: The amount of the strong adhesion material spin coating solution spin coated on the substrate layer is 20-30 μL / cm 2 ; and / or, the amount of the anti-adhesion material spin coating solution spin coated on the substrate layer is 50-80 μL / cm 2 .

9. The method according to claim 5, characterized in that The spin coating comprises a first step of spin coating and a second step of spin coating, wherein the first step of spin coating has a rotation speed between 1000-1500 rpm; the second step of spin coating has a rotation speed between 6000-8000 rpm; and / or, The first step spin coating time is between 10-120 s; the second step spin coating time is between 30-300 s.

10. The method according to claim 9, characterized in that The first step spin coating time is between 60-90 s; the second step spin coating time is between 120-180 s.

11. Use of the medical patch according to any one of claims 1 to 4 or the layered medical patch prepared by the preparation method according to any one of claims 5 to 10 in surgical repair materials.

Images