Method for manufacturing barb-shaped medical tension-reducing bandage based on roller microneedle

Abstract

The invention discloses a method for manufacturing a barb-shaped medical tension-reducing bandage based on a roller microneedle, which comprises the following steps of: pressing the roller microneedle on a template base material according to a preset inclination angle, and taking the template base material distributed with microneedle holes as a microneedle template; a liquid medical polymer material is dripped to the surface of the microneedle template, so that the surface of the microneedle template is uniformly covered with the liquid medical polymer material; slowly demolding the cell clamp in a direction opposite to the arrangement direction of the microneedles to obtain a microneedle patch with barbs orderly arranged on the surface; and slitting the microneedle patch to obtain microneedle slices, and adhering the microneedle slices to a bandage base material to obtain the medical tension-reducing bandage. The method for manufacturing the barb-shaped medical tension-reducing bandage is easy and convenient to operate, efficient and reliable, the skin fixing capacity and the tension-reducing effect of the manufactured medical tension-reducing bandage are improved through the barb-shaped microneedle structure, biocompatibility is good, and the method is suitable for the fields such as drug delivery, wound management and real-time monitoring.

Description

Technical Field

[0001] The invention belongs to the field of microneedles, and in particular relates to a method for making a barbed medical tension-reducing bandage based on roller microneedles. Background Art

[0002] Microneedle technology is an innovative method that can penetrate tissues in a minimally invasive and painless way. It not only avoids the additional scars that may be caused by traditional methods, but also can accurately deliver drugs to the wound site to achieve targeted treatment. Microneedles with special structures show broad application prospects for controlled treatment of wounds. However, in the field of microneedle-mediated wound healing, there are still some technical problems that need to be solved. When existing microneedles are used for wound healing, the dynamic tension change requirements during the wound healing process have not been fully considered, and it is difficult to meet the differentiated requirements for tension reduction effects at different stages. In addition, the existing microneedle designs mostly use an upright needle body structure, which has a certain limitation on its ability to fix on the skin in actual use. The lack of stability between the microneedle and the skin surface makes it show limited tensile properties when responding to skin tension, thereby affecting its potential value in scarless healing. Therefore, a microneedle structure with stable fixation performance and excellent tension reduction effect is developed to achieve scarless healing.

[0003] The microneedle roller is a microneedle device driven by a roller. Its characteristic is that the microneedles densely arranged on the surface of the microneedle roller are used to quickly and evenly form a standardized microchannel structure on the surface of the tissue or material in a short time by rolling. Compared with traditional microneedle devices, the microneedle roller has obvious advantages in ease of operation, efficiency and channel consistency. This device not only shows superior performance in minimally invasive skin treatment, but also provides an efficient auxiliary tool for the manufacture of microneedle templates. The microneedle roller has strong versatility, and commercial microneedles of different specifications are available on the market. Therefore, the characteristics of the microneedle roller are simple, fast, low-cost and highly customizable, making it an ideal choice for the development of microneedles with special structures. Summary of the invention

[0004] The purpose of the invention is to provide a method for making a barbed medical tension-reducing bandage based on a roller microneedle, which can prepare a medical tension-reducing bandage with excellent skin fixation ability, thereby effectively adapting to the dynamic tension changes during wound healing.

[0005] Technical solution: The method for making a barbed medical tension-reducing bandage based on a roller microneedle according to the present invention comprises the following steps:

[0006] Step 1, using a roller microneedle to press onto a template substrate at a predetermined inclination angle, thereby forming orderly arranged microneedle holes inclined at a predetermined inclination angle on the surface of the template substrate, and using the template substrate with distributed microneedle holes as a microneedle template;

[0007] Step 2, dripping liquid medical polymer material onto the surface of the microneedle template, so that the liquid medical polymer material covers the surface of the microneedle template;

[0008] Step 3, after the liquid medical polymer material is solidified, the microneedle patch is slowly demoulded in the opposite direction of the microneedle arrangement through a cell clamp to obtain a microneedle patch with barbs arranged in an orderly manner on the surface;

[0009] Step 4, cutting the microneedle patch into the desired shape and size to obtain microneedle slices, and using a medical-grade adhesive to bond the microneedle slices to a bandage substrate to obtain a medical tension-reducing bandage with orderly arranged barbs.

[0010] Furthermore, in step 1, the length of the microneedles on the microneedle roller used is 0.3 mm, 0.5 mm, 1.0 mm or 1.5 mm.

[0011] Furthermore, in step 1, when the roller microneedle is pressed onto the template substrate at a predetermined inclination angle, the predetermined inclination angle of the microneedle hole on the microneedle template is controlled by adjusting the pressing angle when the roller microneedle contacts the template substrate, so that the predetermined inclination angle ranges from 0° to 90°.

[0012] Furthermore, in step 1, the material of the template substrate is an elastic material.

[0013] Furthermore, in step 2, when dripping liquid medical polymer material onto the surface of the microneedle template, one or two liquid medical polymer materials can be used; if one liquid medical polymer material is used, it is evenly dripped onto the surface of the microneedle template to completely cover the surface of the template, and the bubbles under the covered surface are removed; if two liquid medical polymer materials are used, the first liquid medical polymer material is first completely covered on the surface of the microneedle template so that the first liquid medical polymer material fills each microneedle hole, and then the bubbles under the covered surface of the microneedle template are removed, and then the first liquid medical polymer material on the surface of the microneedle template is scraped off, and then the second liquid medical polymer material is completely covered on the surface of the microneedle template, and the bubbles under the covered surface of the microneedle template are removed again.

[0014] Furthermore, in step 2, the amount of liquid medical polymer material uniformly covering the surface of the microneedle template is 0.2 to 0.4 mL per square centimeter.

[0015] Furthermore, in step 2, after the liquid medical polymer material covers the surface of the microneedle template, the microneedle template completely covered with the liquid medical polymer material is placed in a vacuum drying oven, and the pressure of the vacuum drying oven is reduced from normal pressure 0 MPa to -0.1 MPa. After maintaining the pressure state for 1 minute, the atmosphere is slowly introduced until the pressure in the vacuum drying oven returns to normal pressure 0 MPa.

[0016] Furthermore, in step 3, the material of the microneedle patch is silk fibroin, polyurethane or polyethylene glycol diacrylate.

[0017] Furthermore, in step 3, the orderly arrangement direction of the barbs on the surface of the microneedle patch includes unidirectional arrangement, bidirectional arrangement or staggered arrangement.

[0018] Furthermore, in step 3, the bandage substrate is a medical grade elastic fabric material, including polyamide fiber, polyester fiber or polypropylene fiber.

[0019] Compared with the prior art, the present invention has the following beneficial effects: the method for preparing barbed medical tension-reducing bandage based on roller microneedles disclosed in the present invention adopts roller microneedle technology, and the preparation method is simple and efficient, which not only improves production efficiency but also greatly reduces costs; the specifications, structural configuration and needle body angle (0° to 90°) of the microneedle array on the surface of the medical tension-reducing bandage prepared by the method of the present invention can be flexibly adjusted and customized according to actual needs to meet the needs of different application scenarios; the medical tension-reducing bandage prepared by the method of the present invention also has excellent skin fixation ability, excellent mechanical properties, and good biocompatibility, thereby providing more ideal tension-reducing support and ensuring the best effect in the wound healing process; the medical tension-reducing bandage prepared by the method of the present invention is suitable for fields such as drug delivery, wound management and real-time monitoring. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 This is a schematic diagram of the process of making a barbed medical tension-reducing bandage based on a roller microneedle according to the present invention;

[0021] Figure 2 Detailed analysis diagram of the interaction between the roller microneedle and the template substrate at different angles of the present invention;

[0022] Figure 3 It is a schematic diagram showing that the force applied by the roller microneedle of the present invention when rolling in the horizontal direction is determined by the combined action of gravity and shear force;

[0023] Figure 4 The simulated stress distribution at the initial insertion moment when the roller microneedle of the present invention is rolled and inserted into the template with different tilt angles (angles are about θ=0°, 30°, 45°, 60° and 90°) simulated by COMSOL Multiphysics (scale: 500 μm);

[0024] Figure 5 The relative flexible motion between the roller microneedle and the template simulated by COMSOL Multiphysics of the present invention is used to form a microneedle mold with tilted microneedles (angles of about α = 0°, 30°, 45°, 60° and 90°) (scale bar: 500 μm);

[0025] Figure 6 A schematic diagram of the triboelectric mechanism of the present invention of the barbed medical tension-reducing bandage made of roller microneedles and applied to triboelectric generation;

[0026] Figure 7 The voltage output curves of the barbed medical tension-reducing bandage made of roller microneedles of the present invention under (i-iii) soft friction and hard friction conditions and (iv-vi) slow friction and fast friction conditions;

[0027] Figure 8 The voltage output curves of the barbed medical tension-reducing bandage made of roller microneedles of the present invention with microneedles at different tilt angles (30°, 60°, 90°) under (i-iii) multiple friction cycles and (iv-vi) friction conditions;

[0028] Fig. 9 This is a picture showing the effect of the barbed medical tension-reducing bandage made based on the roller microneedle for tension-reducing healing of mouse wounds (scale: 6 mm);

[0029] Fig.10 Optical images (scale bar: 500 μm) of different arrangement directions of microneedles on the barbed medical tension-relieving bandage made based on roller microneedles of the present invention, including unidirectional (i), bidirectional (ii) or staggered (iii). DETAILED DESCRIPTION

[0030] The present invention is further explained below in conjunction with the accompanying drawings and specific embodiments. The embodiments are implemented based on the technical solution of the present invention. It should be understood that these embodiments are only used to illustrate the present invention and are not used to limit the scope of the present invention.

[0031] like Figure 1 As shown, the method for making a barbed medical tension-reducing bandage based on a roller microneedle disclosed in the present invention comprises the following steps:

[0032] Step 1, using a roller microneedle to press on a template substrate at a predetermined inclination angle, the length of the microneedle on the roller microneedle used is 0.3mm, 0.5mm, 1.0mm or 1.5mm, so that the length of the prepared inclined microneedle is roughly consistent with the selected needle length, and the predetermined inclination angle of the microneedle hole on the microneedle template is controlled by adjusting the pressing angle when the roller microneedle contacts the template substrate, and the angle range of the predetermined inclination angle is 0° to 90°, that is, gradually shifting from a 0° angle perpendicular to the template substrate to a 90° angle close to parallel to the template substrate, thereby forming each microneedle hole arranged in an orderly manner and inclined at a predetermined inclination angle on the surface of the template substrate, the material of the template substrate is an elastic material, such as PDMS or Ecoflex material, and finally the template substrate with distributed microneedle holes is used as a microneedle template;

[0033] Step 2, dripping liquid medical polymer material onto the surface of the microneedle template so that the liquid medical polymer material evenly covers the surface of the microneedle template, with an amount of 0.2 to 0.4 mL per square centimeter;

[0034] Step 3, after the liquid medical polymer material is solidified, the microneedle patch is slowly demolded in the direction opposite to the arrangement direction of the microneedles through the cell clamp to obtain a microneedle patch with barbs arranged in an orderly manner on the surface. The material of the microneedle patch is silk fibroin, polyurethane or polyethylene glycol diacrylate, and the orderly arrangement direction of the barbs on the surface of the microneedle patch includes unidirectional arrangement, bidirectional arrangement or staggered arrangement, such as Fig.10 As shown, Figure i is a unidirectional arrangement, Figures ii and iii are combined into a bidirectional arrangement, and Figure iv is a staggered arrangement. In the unidirectional arrangement, the barbs on the surface of the microneedle patch are tilted in one direction; in the bidirectional arrangement, the barbs on the left side of the microneedle patch surface are tilted to the right, and the barbs on the right side are tilted to the left; in the staggered arrangement, two adjacent barbs on the surface of the microneedle patch are a group, and one of the two barbs in a group is tilted to the left and the other is tilted to the right.

[0035] Step 4, cut the microneedle patch into the required shape and size to obtain microneedle slices, and use a medical-grade adhesive to bond the microneedle slices to a bandage substrate. The medical-grade adhesive is a polyurethane adhesive, and the bandage substrate is a medical-grade elastic fabric material, including polyamide fiber, polyester fiber or polypropylene fiber, to obtain a medical tension-reducing bandage with orderly arranged barbs.

[0036] Furthermore, in step 1, the predetermined inclination angle ranges from 0° to 90°, and the inclination angle can be adjusted according to the required inclination angle during operation. The inclination angle adjustment can be fine-tuned by holding the mold, or can be precisely controlled by devices such as clamps, adjustment knobs or bolts.

[0037] Furthermore, in step 3, the cell clamp is slowly demolded in the direction opposite to the microneedle arrangement to gradually release the adhesion and friction between the microneedle template and the microneedles on the microneedle patch, thereby protecting the microneedle structure.

[0038] Furthermore, in step 2, when dripping liquid medical polymer material onto the surface of the microneedle template, one or two liquid medical polymer materials can be used; if one liquid medical polymer material is used, it is evenly dripped onto the surface of the microneedle template to completely cover the surface of the template, and the bubbles under the covered surface are removed; if two liquid medical polymer materials are used, the first liquid medical polymer material is first completely covered on the surface of the microneedle template so that the first liquid medical polymer material fills each microneedle hole, and then the bubbles under the covered surface of the microneedle template are removed, and then the first liquid medical polymer material on the surface of the microneedle template is scraped off, and then the second liquid medical polymer material is completely covered on the surface of the microneedle template, and the bubbles under the covered surface of the microneedle template are removed again.

[0039] Furthermore, in step 2, in order to ensure that the liquid medical polymer material fills each microneedle hole, the microneedle template completely covered with the liquid medical polymer material is placed in a vacuum drying oven. In this process, the pressure of the vacuum drying oven is first reduced from normal pressure 0MPa to -0.1MPa, and the pressure state is maintained for 1 minute. Subsequently, the atmosphere is slowly introduced until the pressure in the vacuum drying oven returns to normal pressure 0MPa.

[0040] Furthermore, residual bubbles generated under the surface of the microneedle template covered with the liquid medical polymer material after vacuum drying can be removed using a 5 ml plastic dropper, thereby completely removing all bubbles.

[0041] Furthermore, in step 4, when the microneedle patch is cut into desired shapes and sizes, it is cut by laser cutting or a high-precision scalpel.

[0042] Embodiment 1:

[0043] 1) A mixed material of PDMS (with a curing agent ratio of 17:1) and Ecoflex (A:B = 1:1) in a ratio of 10:1 was selected as the template substrate, and a roller microneedle was used to make a microneedle template. A commercial roller microneedle with a microneedle length of 0.5 mm was selected for production. Before pressing, the template substrate was stretched to 0.4 times the original length along both ends through a clamp to prevent the needle body from being formed too thin. The stretched template substrate was fixed on the workbench, and the inclination angle between the template substrate and the workbench was adjusted (such as 0°, 30°, 60° or 90°). When the template substrate was stretched, the roller microneedle was evenly rolled from the horizontal end to the inclined end in the horizontal direction to press and form a microneedle template.

[0044] The specific details are as follows: On the surface of a template substrate that is stretched and tilted at a certain angle (θ), the roller microneedle rolls horizontally from right to left. Under this condition, the interaction between the roller microneedle and the surface of the template substrate remains in the transition area from the horizontal plane of the template substrate to the tilted area. The tilt angle (θ) of the template substrate surface affects the insertion path of the roller microneedle, forming a microneedle template with microneedle holes of corresponding tilt angle (α) in the transition area. This rolling process can control the formation morphology of the microneedle holes, ensure that the roller microneedle maintains a stable contact point on the surface of the template substrate, and accurately replicates the tilt angle (θ) of the template substrate, thereby forming a microneedle template with microneedle holes of corresponding tilt angle (α), such as Figure 1 and 2 shown.

[0045] When rolling microneedles are pressed, the force on the microneedle holes is determined by the combined direction of the normal force (perpendicular to the template substrate surface) and the tangential force (along the rolling direction): F 总 =F 法 +F 切. The greater the inclination angle of the template substrate, the higher the proportion of the tangential force, and the greater the angle at which the microneedle deviates from the vertical direction. Specifically, when the axis of the roller microneedle is at a non-vertical angle to the surface of the template substrate, the pressing direction of the microneedle will deviate from the vertical direction, forming an oblique insertion deformation path. At the same time, the elastic template substrate will undergo asymmetric local deformation under stress. The rolling of the roller microneedle on the template substrate produces a directional pressure gradient, causing the deformation of the template substrate around the microneedle to change toward the rolling direction, further causing the microneedle to tilt, such as Figure 3 shown.

[0046] like Figure 4 As shown, the simulated stress distribution at the initial insertion moment when the roller microneedle is rolled and inserted into the template substrate with different inclination angles (angles are approximately θ = 0°, 30°, 45°, 60° and 90°) simulated by COMSOL Multiphysics. The simulation explored the effect of the template substrate inclination angle (θ) on the microneedle inclination angle (α) of the microneedle mold. The simulation results at the initial insertion moment between the rolling microneedle and the template substrate show that when θ = 0°, the stress is concentrated at the puncture site. As θ increases to 30°, 45° and 60°, the stress distribution becomes wider, indicating that local deformation has occurred. It is worth noting that when θ = 90°, the stress distribution is more uneven, which is not conducive to the production process.

[0047] like Figure 5 As shown, the relative flexible motion between the roller microneedle and the template substrate simulated by COMSOL Multiphysics forms a microneedle mold with an inclined angle microneedle (angles are approximately α = 0°, 30°, 45°, 60° and 90°). In addition, the results of the relative flexible motion between the roller microneedle and the template substrate show that at an angle of 0°, the stress distribution around the microneedle is symmetrical and is the largest along the vertical axis, which can theoretically increase the penetration depth. As the angle increases to 30°, 45° and 60°, the stress distribution changes, and the lateral force vector increases, which can improve the adhesion stability of the microneedle in the tissue. At an angle of 90°, the microneedle is almost parallel to the template substrate, the vertical force is minimal, and the lateral contact area is maximized, so it is suitable for applications that require grasping rather than deep penetration. Theoretical modeling shows that the gradual increase in the inclination angle of the microneedle can effectively control the direction of the force, and the inclined structure can evenly distribute stress over the entire surface and reduce local stress concentration.

[0048] 2) drip a mixture of silk fibroin solution and PU solution in a volume ratio of 7:3 onto the microneedle template after the above treatment, so that it completely covers the microneedle template to a thickness of 1mm. Place it in a vacuum drying oven and reduce the pressure to -0.1MPa. After keeping it for 1min, open the atmosphere. Repeat the above vacuum drying step twice to ensure that the silk fibroin solution and the PU mixture fill each microneedle hole. For the residual bubbles generated under the surface of the microneedle template covered with the silk fibroin solution and the PU mixture after vacuum drying, use a 5ml plastic dropper to remove them. After removing the bubbles, place the microneedle template at room temperature to dry for 12h, and then slowly demold it in the opposite direction of the microneedle arrangement through the cell clamp to obtain a transparent microneedle patch with an inclined barb structure.

[0049] 3) The mixed Ecoflex (A:B=1:1) liquid was adhered to the microneedle surface of the microneedle patch and cured at room temperature for 12 hours, and a thin copper sheet was attached to the backing surface of the microneedle patch as an induction electrode. It was bonded to the medical grade elastic fabric material polyamide fiber using a medical grade polyurethane adhesive to obtain a medical tension-reducing bandage with an ordered barbed structure.

[0050] 4) The barbed medical bandage obtained above is used to integrate a triboelectric nanogenerator (TENG). When charged objects are periodically in contact, the positive charge on the electrode changes, such as Figure 6 As shown, the human skin and the Ecoflex surface on the microneedle surface exhibit triboelectric positive and negative properties, respectively. After contact, positive and negative charges are evenly distributed on the surface of the skin and the surface of the Ecoflex on the microneedle surface. When the skin is separated from the Ecoflex surface on the microneedle surface, positive charges are induced, causing electrons to flow to the ground until the induced positive charges are balanced with the negative charges on the Ecoflex surface on the microneedle surface. Conversely, electrons flow from the ground into the microneedle patch, generating an opposite current until a balance is reached, at which point the loop is maintained.

[0051] 5) The open circuit voltage (Voc) of the above-mentioned TENG under various working conditions was measured by a high-precision oscilloscope to quantitatively evaluate the electrical output performance in energy conversion.

[0052] Specifically, as the friction intensity increases, the voltage amplitude increases significantly. Figure 7 As shown in Figure 2, the voltage output exhibits a stable periodicity with a peak value reaching about 4.5 V. When the friction intensity exceeds a certain threshold, the peak voltage decreases slightly, probably because the surface wear or microscopic deformation destroys the uniform charge accumulation, as shown in Figure 2. Figure 7 As shown in Figures i to iii in Figure 1, soft friction promotes effective charge accumulation, while hard friction may reduce the charge accumulation efficiency due to surface damage. In addition, as the friction frequency increases, the voltage waveform responds faster, thereby improving the cycle efficiency per unit time, as shown in Figure 2. Figure 7This phenomenon indicates that higher friction frequency shortens the charge recombination interval, thereby improving the charge transfer efficiency. These findings further confirm that the above-mentioned TENG exhibits high sensitivity under different friction conditions, responds quickly to changes in friction frequency, and exhibits good dynamic performance.

[0053] In terms of triboelectric stability, the voltage output remains highly consistent over multiple friction cycles, e.g. Figure 8 Even after multiple friction cycles, the voltage waveform remains stable without obvious attenuation, indicating that the above TENG maintains stable electrical performance under cyclic friction loads, as shown in Figure 2. Figure 8 This stability is critical for long-term wearable applications and ensures durability in actual use. Further study of the effect of different microneedle angles on the triboelectric response revealed different results. Throughout the experiment, given the constant mechanical conditions (contact frequency and force), the contact frequency showed relative consistency, as shown in Figures i-iii. Figure 8 As shown in Figures iv to vi in ​​. However, obvious differences in the amplitude of the voltage waveform were observed. The microneedles with a 30° inclination angle mainly exhibited sliding friction, resulting in unstable charge accumulation, lower voltage, and obvious noise. The strong noise may be related to the contact instability and random fluctuations generated during the friction process. The microneedles with a 60° inclination angle are located between sliding friction and vertical contact, showing relatively uniform charge accumulation and stable voltage signals. In contrast, due to the larger contact area of ​​the microneedles with a 90° inclination angle, sliding friction is dominant, resulting in more stable charge accumulation, higher voltage amplitude, and smooth waveforms with minimal noise. This indicates that the 90° inclination microneedles exhibit higher stability, more consistent contact, and a more uniform charge transfer process. Overall, optimizing the microneedle angle can achieve more efficient and stable charge transfer, thereby improving voltage output stability and responsiveness.

[0054] Embodiment 2:

[0055] 1) A mixed material of PDMS (ratio to curing agent is 17:1) and Ecoflex (A:B=1:1) in a ratio of 10:1 was selected as the template substrate, and a roller microneedle was used to make a microneedle template. A commercial roller microneedle with a microneedle length of 0.5 mm was selected for production. Before pressing, the template substrate was stretched to 0.4 times the original length through a clamp along both ends to prevent the needle body from being formed too thin. The stretched template substrate was fixed on the workbench, and the inclination angle between the template substrate and the workbench was adjusted (such as 0°, 30°, 60° or 90°). When the template substrate was stretched, the roller microneedle was evenly rolled from the horizontal end to the inclined end in the horizontal direction to press and form a microneedle template.

[0056] 2) Drop 2 ml of PEGDA solution onto a 5 cm × 1.5 cm microneedle template, then place it in a vacuum drying oven and reduce the pressure to -0.1 MPa. After maintaining for 1 min, open the atmosphere and repeat the above steps twice to ensure that PEGDA fills all microneedle holes. Then use a surgical blade to gently scrape off excess PEGDA solution on the surface of the microneedle template, and then place the microneedle template under ultraviolet light for curing for 2-5 min (depending on the UV light intensity).

[0057] 3) drip a mixture of silk fibroin solution and PU solution in a volume ratio of 7:3 onto the microneedle template treated as above, so that it completely covers the mold surface to a thickness of 1 mm. Dry it at room temperature for 12 hours, and slowly demould it in the opposite direction of the microneedle arrangement through a cell clamp to obtain a transparent microneedle patch with an inclined barb structure. Then use a medical grade polyurethane adhesive to bond it to a medical grade elastic fabric material polyamide fiber to obtain a medical tension-reducing bandage with an ordered barb-shaped structure.

[0058] 4) The barbed medical tension-reducing bandage obtained above was used to reduce the tension of high-tension strip wounds on the back of mice for scar-free healing. The results are as follows: Fig. 9 As shown, the medical tension-relieving bandage has the ability to be used for wound tension relief and scar-free healing.

[0059] Specifically, the experiment was conducted on the back of mice. To ensure the comparability of the initial wound size between experimental groups, a standardized 2 cm linear excisional wound was created on the back of each mouse using a sterile scalpel under general anesthesia. The initial wound size was recorded immediately after surgery, and digital images were taken on day 0. The wound length was measured with a calibrated ruler to ensure consistency. The tension relief and wound healing ability of the barbed medical tension-relieving bandage were evaluated by comparing the effects of different treatment groups. The animals were divided into five groups: control group, patch group without microneedle structure, barbed medical tension-relieving bandage group loaded with hEGF drug, barbed medical tension-relieving bandage and friction nanogenerator integrated group, and barbed medical tension-relieving bandage and friction nanogenerator integrated group loaded with hEGF drug. The anti-inflammatory and anti-infective properties of hEGF help to create a good microenvironment around the wound, thereby reducing the risk of infection. The hEGF gel was encapsulated in the barbed medical tension-relieving bandage to evaluate its synergistic effect with the barbed medical tension-relieving bandage in tension relief and accelerated wound healing. The changes in wound width were recorded regularly during the experiment (1st, 3rd, 5th, 7th, 9th, 12th, and 14th days). Fig. 9The barbed medical tension-reducing bandage and friction nanogenerator integrated group loaded with hEGF drug achieved the best healing effect on the 14th day. Through the combined effects of the barbed medical tension-reducing bandage, hEGF and frictional electrical stimulation, the tension was significantly reduced and wound healing was accelerated. Specifically, the control group showed obvious inflammation at the wound edge on the first day, and the wound healed slowly in the later period, with obvious scars. The barbed medical tension-reducing bandage and friction nanogenerator integrated group had an enhanced healing effect on the 7th day, which may be because frictional electrical stimulation activated the mechanical sensitive pathway, thereby promoting cell adhesion and healing. The barbed medical tension-reducing bandage and friction nanogenerator integrated group loaded with hEGF drug had a faster wound area contraction from the 3rd day, reflecting the synergistic effect of hEGF-induced cell proliferation with the mechanical support provided by the tilted microneedles and the microfluidic channels, maintaining optimal wound hydration and nutrient delivery. In addition, frictional electrical stimulation can further promote tissue regeneration and wound contraction through local electric fields.

[0060] As described above, although the present invention has been shown and described with reference to specific preferred embodiments, it should not be construed as limiting the present invention itself. Various changes in form and details may be made without departing from the spirit and scope of the present invention as defined in the appended claims.

Claims

1. A method for making a barbed medical tension-reducing bandage based on a roller microneedle, characterized in that: The steps include: Step 1, using a roller microneedle to press onto a template substrate at a predetermined inclination angle, thereby forming orderly arranged microneedle holes inclined at a predetermined inclination angle on the surface of the template substrate, and using the template substrate with distributed microneedle holes as a microneedle template; Step 2, dripping liquid medical polymer material onto the surface of the microneedle template, so that the liquid medical polymer material covers the surface of the microneedle template; Step 3, after the liquid medical polymer material is solidified, the microneedle patch is slowly demoulded in the opposite direction of the microneedle arrangement through a cell clamp to obtain a microneedle patch with barbs arranged in an orderly manner on the surface; Step 4, cutting the microneedle patch into the desired shape and size to obtain microneedle slices, and using a medical-grade adhesive to bond the microneedle slices to a bandage substrate to obtain a medical tension-reducing bandage with orderly arranged barbs.

2. The method for making a barbed medical tension-reducing bandage based on roller microneedles according to claim 1, characterized in that: In step 1, the length of the microneedles on the microneedle roller used is 0.3 mm, 0.5 mm, 1.0 mm or 1.5 mm.

3. The method for making a barbed medical tension-reducing bandage based on roller microneedles according to claim 1, characterized in that: In step 1, when the roller microneedle is pressed onto the template substrate at a predetermined inclination angle, the predetermined inclination angle of the microneedle hole on the microneedle template is controlled by adjusting the pressing angle when the roller microneedle contacts the template substrate, so that the predetermined inclination angle ranges from 0° to 90°.

4. The method for making a barbed medical tension-reducing bandage based on roller microneedles according to claim 1, characterized in that: In step 1, the template substrate is made of elastic material.

5. The method for making a barbed medical tension-reducing bandage based on roller microneedles according to claim 4, characterized in that: In step 2, when dripping liquid medical polymer material onto the surface of the microneedle template, one or two liquid medical polymer materials can be used; if one liquid medical polymer material is used, it is evenly dripped onto the surface of the microneedle template to completely cover the surface of the template, and the bubbles under the covered surface are removed; if two liquid medical polymer materials are used, the first liquid medical polymer material is first completely covered on the surface of the microneedle template so that the first liquid medical polymer material fills each microneedle hole, and then the bubbles under the covered surface of the microneedle template are removed, and then the first liquid medical polymer material on the surface of the microneedle template is scraped off, and then the second liquid medical polymer material is completely covered on the surface of the microneedle template, and the bubbles under the covered surface of the microneedle template are removed again.

6. The method for making a barbed medical tension-reducing bandage based on roller microneedles according to claim 1, characterized in that: In step 2, the amount of liquid medical polymer material uniformly covering the surface of the microneedle template is 0.2 to 0.4 mL per square centimeter.

7. The method for making a barbed medical tension-reducing bandage based on roller microneedles according to claim 1, characterized in that: In step 2, after the liquid medical polymer material covers the surface of the microneedle template, the microneedle template completely covered with the liquid medical polymer material is placed in a vacuum drying oven, and the pressure of the vacuum drying oven is reduced from normal pressure 0 MPa to -0.1 MPa. After maintaining this pressure state for 1 minute, the atmosphere is slowly introduced until the pressure in the vacuum drying oven returns to normal pressure 0 MPa.

8. The method for making a barbed medical tension-reducing bandage based on roller microneedles according to claim 1, characterized in that: In step 3, the material of the microneedle patch is silk fibroin, polyurethane or polyethylene glycol diacrylate.

9. The method for making a barbed medical tension-reducing bandage based on roller microneedles according to claim 1, characterized in that: In step 3, the orderly arrangement direction of the barbs on the surface of the microneedle patch includes unidirectional arrangement, bidirectional arrangement or staggered arrangement.

10. The method for making a barbed medical tension-reducing bandage based on roller microneedles according to claim 1, characterized in that: In step 3, the bandage substrate is a medical grade elastic fabric material including polyamide fiber, polyester fiber or polypropylene fiber.

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