Composite layer structure patch for breast reconstruction and preparation method and application thereof

Abstract

The invention relates to the technical field of breast reconstruction, and discloses a composite layer structure patch for breast reconstruction and a preparation method and application thereof.The composite layer structure patch for breast reconstruction sequentially comprises a surface layer, a drug controlled release layer and a surface layer, the core layer is a shape memory supporting layer and is used for providing mechanical support, modifying the breast shape and improving the attractiveness; the bottom layer is an anti-adhesion isolation layer, and the key effect of the anti-adhesion isolation layer is to construct an effective physical barrier between the skin and chest wall muscles, so that the problems of appearance of the prosthesis contour, stiff breast form and the like caused by abnormal adhesion are fundamentally avoided. By means of the three-layer function integrated design of medicine controlled release, mechanical support and long-acting adhesion prevention, the clinical pain points that an existing patch is single in function, prone to adhesion and poor in aesthetic effect are systematically solved, and an innovative solution is provided for breast reconstruction which is natural in form, good in function and stable for a long time.

Description

Technical Field

[0001] This invention relates to the field of breast reconstruction technology, specifically to a composite layer structure patch for breast reconstruction, its preparation method, and its application. Background Technology

[0002] The statements in this section provide only background information relevant to the disclosure of this application and may not constitute prior art.

[0003] In the field of breast cancer treatment, breast reconstruction after mastectomy is a crucial step in restoring the patient's physical integrity and mental well-being. Surgical mesh-assisted breast reconstruction has become a mature technique, typically used in conjunction with autologous tissue flaps or prosthetic implants. These mesh materials, based on their degradation characteristics, mainly include non-absorbable synthetic materials (such as polypropylene and polyester), absorbable materials (such as acellular dermal matrix ADM), and composite materials. Their core function is to provide mechanical support for the implant or flap, assist in shaping, and hopefully guide the establishment of a well-vascularized regenerative framework in the tissue defect area.

[0004] However, currently widely used patches in clinical practice, such as acellular dermal matrix (ADM) and polylactic acid (PLA) patch TiLOOP®, still have significant limitations in terms of anti-adhesion, mechanical compatibility, and controllable degradation. While ADM has good tissue compatibility, its degradation rate is uncontrollable, easily triggering excessive inflammatory responses, and it lacks sustained drug release. More importantly, ADM cannot effectively prevent tissue adhesion, easily leading to problems such as prosthesis outline protrusion and capsular contracture postoperatively. TiLOOP® patches have a single function, lack multi-layered synergistic design, and cannot achieve controlled drug release and long-term anti-adhesion; its mechanical properties and degradation rate are difficult to match the long-term needs of breast reconstruction, easily leading to support failure or the risk of secondary surgery.

[0005] Besides the limitations of the patch material itself, the inherent shape and properties of the implant are also key factors affecting the reconstruction results. Implants typically have a fixed shape (round or anatomical) and texture, and their contours are often too rounded and full, lacking the slight ptosis and soft edge transition of a natural breast. Even if these problems are alleviated by improving the implant shape, such as using a teardrop design, the implant edges may still be palpable or visible. Furthermore, capsular contracture leading to breast hardening, deformation, excessively high positioning, and the long-term potential for rippling effects remain prominent, resulting in a significant difference between the reconstructed breast and natural tissue in both static appearance and dynamic feel.

[0006] From a functional design perspective, traditional patches typically integrate with the implant by encapsulating it or forming a pocket to hold it, and are then fixed to the pectoralis major muscle. These patches primarily function as passive biomechanical materials, focusing on "holding" the implant and restricting its displacement. Their active modification of the natural curvature and contour of the reconstructed breast is limited, making it difficult to fundamentally improve the aesthetic outcome of the reconstructed breast. A more significant challenge arises from the biological reactions triggered after patch implantation. After implantation, the patch inevitably triggers a foreign body reaction and the wound healing process. The core aspect is the adhesion and integration of the patch with surrounding host tissues (such as subcutaneous tissue, pectoralis major muscle, and residual chest wall fascia). While moderate adhesion contributes to patch fixation and mechanical support, excessive, abnormal, or anatomically incorrect adhesions can lead to a series of clinical complications. These include: limited chest wall movement and chronic pain, abnormal breast shape and dynamic distortion, interference with subsequent tumor monitoring and diagnosis, and increased difficulty and risk of secondary surgeries. These complications caused by adhesions seriously affect patients' postoperative quality of life and physical and mental health, and directly reduce patients' acceptance of breast reconstruction techniques.

[0007] In summary, while existing patch technologies provide mechanical support, they generally suffer from insufficient anti-adhesion function, lack of active drug intervention capability, and mismatch with tissue regeneration timing. Therefore, there is a need to develop a biomimetic composite patch that integrates multiple functions such as anti-adhesion, controlled drug release, and intelligent mechanical support to comprehensively improve the clinical outcomes and patient satisfaction of breast reconstruction. Summary of the Invention

[0008] The purpose of this invention is to overcome the shortcomings of existing patches, such as poor mechanical adaptability, limited functionality, and poor anti-adhesion properties, and to provide a composite layered patch for breast reconstruction, its preparation method, and its application. This patch possesses multiple functions, including anti-adhesion and anti-infection properties, and can provide support while preventing abnormal adhesions, thus reducing the impact of adhesions. This effectively reduces postoperative complications and improves the aesthetics and long-term stability of the reconstructed breast.

[0009] The technical solution of the present invention is as follows: In one aspect, this invention provides a composite layer structure patch for breast reconstruction, comprising: Surface layer: Drug-controlled release layer, which contains therapeutic drugs and can trigger the controlled release of drugs in response to specific physiological or pathological conditions at the implantation site, thereby regulating the local microenvironment; Core layer: Shape memory support layer. After implantation, it can recover from the first shape (temporary compressed shape) to the preset second shape (three-dimensional anatomical shape) under specific triggering conditions (such as body temperature), providing stable and adaptive mechanical support for the implant and actively modifying the breast contour to improve its natural sagging and appearance.

[0010] Bottom layer: Anti-adhesion isolation layer, whose core function is to effectively prevent the adhesion and penetration of cells (especially fibroblasts), thereby forming a physical barrier between the skin and chest wall muscles to avoid the formation of abnormal scar adhesions.

[0011] According to a preferred embodiment, the condition triggering of the surface layer specifically includes one or more of the following: pH response, enzyme response, temperature response, redox response, or degradation response.

[0012] According to a preferred embodiment, the pH-responsive sustained drug release is achieved through one or more of the following controlled-release polymers: chitosan and its derivatives, sodium alginate, polyacrylic acid polymers, and polymethacrylic acid polymers; The enzyme-responsive sustained release of the drug is achieved through one or more of the following controlled-release polymers: gelatin, collagen, hyaluronic acid, and synthetic peptides / polymers containing specific enzyme cleavage sites; The sustained release of the drug in the degradation response is achieved by one or more of the following controlled-release polymers: polylactic acid, polyglycolic acid, polycaprolactone, polylactic-co-hydroxyacetic acid copolymer, polyhydroxy fatty acid ester, polyorthoester or polyanhydride.

[0013] The drugs contained in the surface layer can be selected from one or more of anti-inflammatory drugs, antibiotics, anti-tumor drugs, growth factors, or anticoagulants.

[0014] According to a preferred embodiment, the shape memory properties of the core layer are achieved through mechanisms such as thermal triggering, water triggering, light triggering, or pH triggering. A thermally responsive polymer (such as poly(N-isopropylacrylamide)) is preferred. Below its critical dissolution temperature (approximately 32-34°C), its molecular chains extend in water; however, when the ambient temperature rises to body temperature (37°C, the triggering condition), the molecular chains dehydrate and contract dramatically. This contraction process compresses the drug carrier matrix, thereby driving rapid drug release, acting as a "thermal trigger switch."

[0015] The shape memory support layer is configured to have a first shape and a second shape. The first shape can be a compressible shape that facilitates implantation, and the second shape can be an extended shape that provides mechanical support within the body. It can switch between the first and second shapes under specific conditions. Before implantation, the layer can be compressed into the first shape, such as a thin sheet or roll, a temporary shape that is easy to implant. After implantation, it automatically recovers to a preset extended three-dimensional shape that conforms to the inframammary fold and chest wall curvature under body temperature triggering. The upper part is smooth, and the lower part is full. The specific curvature can be adaptively adjusted and set according to different patients, making the newly constructed breast shape more natural, rounded, and full of space, improving aesthetics.

[0016] Preferably, the shape memory support layer is configured as an integrally molded continuous porous mesh structure, exhibiting excellent structural integrity and fatigue resistance. This structure not only facilitates cell ingrowth and biointegration but also disperses the centripetal contractile force of the capsule, thereby effectively resisting capsule contracture. The core layer material can be selected from at least one of polycaprolactone, polylactic acid, polylactic-co-hydroxyacetic acid copolymer, polyurethane, polydioxanone, or polyhydroxyalkanoates.

[0017] According to a preferred embodiment, the bottom layer is prepared using a polymer with anti-cell adhesion function or a polymer containing anti-adhesion factors.

[0018] According to a preferred embodiment, the polymer with anti-cell adhesion function includes one or more of polyethylene glycol and its derivatives, polyvinylpyrrolidone, polyethylene oxide, polyacrylamide, phospholipid polymers, or zwitterionic polymers. The anti-adhesion factor is one or more of heparin, hirudin, hyaluronic acid, silk fibroin, and specific anti-cell adhesion peptides.

[0019] According to a preferred embodiment, the surface layer, core layer and bottom layer are connected by physical entanglement, chemical crosslinking, adhesive bonding or electrospinning integral molding.

[0020] For example, the surface drug-releasing layer is electrospun onto the side of the core layer facing away from the bottom layer, enabling conditionally triggered drug release. Furthermore, the electrospinning process creates numerous nanopores in the surface layer, allowing cells to grow into the shape memory support layer, thus facilitating tissue connection with the patch on the surface. The design of the bottom layer makes it difficult for cells to penetrate, preventing further tissue growth and connection with the pectoralis major muscle. This allows the implant to move naturally within the space defined by the patch, conforming to the body's posture, and with the support of tissue fluid, the breast appears more natural and aesthetically pleasing.

[0021] According to a preferred embodiment, the total thickness of the patch consisting of the surface layer, core layer, and bottom layer is 1-2 mm, and the overall thickness is thin.

[0022] According to a preferred embodiment, the surface layer, core layer, and bottom layer are all prepared using biodegradable materials, and the degradation rates of each layer satisfy the following order: degradation time of the bottom layer > degradation time of the core layer > degradation time of the surface layer. By selecting materials with different chemical backbones and controlling their microstructure, the intrinsic basis for differential degradation is established. Specifically, this can be achieved through material selection and structural control: the degradation time of the surface layer is designed to be 4-12 weeks to ensure that its drug release function is synchronized with the initial tissue healing stage; the degradation time of the core layer is designed to be 1-2 years to provide mechanical support covering the critical period of tissue regeneration; and the degradation time of the bottom layer is designed to be more than 10 years to ensure that it can provide long-term anti-adhesion protection throughout the entire life cycle in which the prosthesis needs to be stable. For example, the surface layer can use low molecular weight PLGA with high porosity to accelerate degradation; the core layer can use medium molecular weight PLLA to balance degradation and mechanical properties; and the bottom layer can use high molecular weight, high crystallinity and dense PCL to achieve ultra-slow degradation.

[0023] Compared with existing technologies, the advantages of this invention are: 1. A composite layer structure patch for breast reconstruction, through functional layered design (intelligent response drug-loaded surface layer, shape memory support core layer, and anti-adhesion bottom layer), simultaneously achieves targeted drug release triggered by the lesion microenvironment, three-dimensional mechanical support for dynamic recovery after implantation, and long-term tissue anti-adhesion, significantly improving the overall performance of the patch. 2. A composite layer structure patch for breast reconstruction, using a shape memory polymer (such as PCL / PLGA / PU) with heat / water / light / pH trigger response, so that the patch can be temporarily deformed into an easily implantable shape (such as two-dimensional) outside the body, and automatically restores the preset three-dimensional structure after implantation to provide precise anatomical support, greatly simplifying the surgical operation; 3. A composite layered patch for breast reconstruction, with three layers matched to differentiated degradation time gradients (surface layer 4-12 weeks, core layer 1-2 years, bottom layer 10-15 years), ensuring that drug release is synchronized with the initial tissue healing, mechanical support covers the critical regeneration period, and anti-adhesion function is effective for a long time, perfectly meeting the needs of tissue regeneration sequence. 4. This invention optimizes the balance between cell infiltration / vascularization ability, mechanical support strength and implantation flexibility by precisely controlling the porous structure of the core layer (porosity 30%-70%, pore size 30-800μm) and the overall thickness (1-2mm).

[0024] 5. This invention constructs an efficient physical and biochemical barrier by introducing materials with both hydrophilicity and anti-cell adhesion functions (such as zwitterionic polymers and phospholipid polymers) and exogenous anti-adhesion factors (such as heparin and RGD antagonists) at the bottom layer, which significantly reduces the risk of postoperative tissue adhesion.

[0025] 6. This invention uses interlayer composite processes such as physical entanglement, chemical crosslinking, and electrospinning to ensure a firm bond at the interface of the three-layer structure, avoids interlayer separation after implantation, and ensures the structural integrity and functional reliability of the device.

[0026] 7. By adopting a fully biodegradable material system and the above-mentioned synergistic design, this invention expands the application of the patch in various soft tissue repair fields such as breast reconstruction, hernia repair, dura mater repair, and pelvic floor repair, and has excellent biocompatibility and long-term safety. Attached Figure Description

[0027] Figure 1 This is a cross-sectional view of the overall structure of a composite layered patch used for breast reconstruction. Figure 2 This image shows the usage status and enlarged partial disassembly view of a composite layered patch used for breast reconstruction.

[0028] Figure labeling: 1-patch, 100-surface layer, 200-core layer, 300-bottom layer. Detailed Implementation

[0029] The specific embodiments listed in this invention are merely examples, and the invention is not limited to the specific embodiments described below. For those skilled in the art, any equivalent modifications and substitutions to the embodiments described below are also within the scope of this invention. Therefore, all equivalent transformations and modifications made without departing from the spirit and scope of this invention should be covered within its scope. Where specific conditions are not specified in the embodiments, conventional conditions or conditions recommended by the manufacturer shall apply. All reagents or instruments whose manufacturers are not specified are commercially available conventional products. To better illustrate this invention, numerous specific details are provided in the following detailed embodiments. Those skilled in the art should understand that this invention can be practiced even without certain specific details. In other embodiments, methods, means, equipment, and steps well known to those skilled in the art are not described in detail in order to highlight the main points of this invention.

[0030] Unless otherwise defined, all technical and scientific terms used herein have the same meanings as commonly understood by one of ordinary skill in the art. Unless otherwise specified, all units used in this specification are International Standard Units (SI), and all numerical values ​​and ranges appearing in this invention should be understood to include systematic errors unavoidable in industrial production.

[0031] The features and performance of the present invention will be further described in detail below with reference to embodiments.

[0032] Example 1 This embodiment details the specific composition of the composite layer structure patch 1 for breast reconstruction provided by the present invention.

[0033] In one aspect, this invention provides a composite layer structure patch 1 for breast reconstruction, such as... Figure 1 and Figure 2 As shown, the patch includes, in sequence: a surface layer 100 with drug sustained-release function, a core layer 200 for providing mechanical support, and a bottom layer 300 with an anti-adhesion isolation layer. The surface layer 100 and the bottom layer 300 assist the core layer 200 in fulfilling its mechanical support function, avoiding adverse reactions, and improving the overall performance of the patch.

[0034] Surface layer 100 is prepared by mixing a conditionally responsive biopolymer with a therapeutic drug. Its drug release mechanism can be conditionally triggered, specifically including one or more of the following: pH response, enzyme response, temperature response, redox response, or material degradation response. The drug contained is selected from one or more of anti-inflammatory drugs (such as dexamethasone), antibiotics (such as gentamicin), antitumor drugs (such as paclitaxel), growth factors (such as VEGF), or anticoagulants (such as heparin). For example, the pH response occurs when the pH of the microenvironment in which the patch is located is greater than or less than a certain threshold, at which point the drug contained in surface layer 100 begins to be slowly released. The enzyme response occurs, for example, when a certain degrading enzyme is present in the microenvironment, or when the activity of a certain degrading enzyme is greater than a certain value, at which point the drug contained in surface layer 100 begins to be slowly released.

[0035] The sustained release of the enzyme-responsive drug is achieved through the following controlled-release polymer: the surface layer 100 is prepared using one or more of gelatin, collagen, hyaluronic acid, and synthetic peptides / polymers containing specific enzyme cleavage sites.

[0036] The sustained release of the drug in the degradation response is achieved by the following controlled-release polymer: the surface layer 100 is prepared from one or more of polylactic acid, polyglycolic acid, polycaprolactone, polylactic-hydroxyacetic acid copolymer, polyhydroxy fatty acid ester, polyorthoester or polyanhydride.

[0037] The core layer 200 uses a material such as a shape memory material, which is configured to have a first shape and a second shape, and can switch between the first shape and the second shape under specific conditions to maintain support. For example, it can be configured to a shape that is easy to implant in the body, such as a sheet, during implantation; and after implantation, it can recover the shape of its three-dimensional support structure based on body temperature, light, water, pH or other factors.

[0038] According to a preferred embodiment, the shape memory support material of the core layer 200 is at least one of the following materials: polycaprolactone, polylactic acid, polyglycolic acid, polylactic acid-glycolic acid copolymer, polyurethane, polydioxanone or polyhydroxyalkanoate.

[0039] Triggering conditions and materials: For example, polycaprolactone (PCL) or polyester-based polyurethane (PU) is used, and its glass transition temperature (Tg) is precisely set between 35-38°C through molecular design. After implantation, it can automatically return to the preset shape under stimulation at body temperature (approximately 37°C).

[0040] According to a preferred embodiment, the bottom layer 300 is an anti-adhesion isolation layer used to prevent cell adhesion and tissue adhesion.

[0041] The anti-adhesion isolation layer can be implemented in any of the following or other feasible ways: Option 1 (material itself is anti-adhesion): Prepared using polymers with inherent anti-cell adhesion function, such as polyethylene glycol (PEG) and its derivatives, zwitterionic polymers (such as polysulfobetaine) or phospholipid polymers.

[0042] Option 2 (Surface Modification Anti-Adhesion): Grafting or blending anti-adhesion factors, such as heparin, hyaluronic acid, or specific anti-cell adhesion peptides (such as RGD antagonists), onto a polymer substrate.

[0043] Example of a specific implementation scheme: Polyethylene glycol (PEG) grafting scheme: Hydrophilic PEG molecules are grafted onto the surface of the underlying material to form a physical barrier that prevents cell adhesion through its strong hydration.

[0044] Phosphorylcholine polymer solution: The underlying material is prepared using a biomimetic phosphorylcholine-based polymer to simulate the cell membrane surface environment, giving the material an "invisible" property, thereby effectively resisting cell adhesion.

[0045] According to a preferred embodiment, the polymer with anti-cell adhesion function includes one or more of polyethylene glycol and its derivatives, polyvinylpyrrolidone, polyethylene oxide, polyacrylamide, phospholipid polymers, or zwitterionic polymers. The anti-adhesion factor is one or more of heparin, hirudin, hyaluronic acid, silk fibroin, and specific anti-cell adhesion peptides.

[0046] According to a preferred embodiment, the surface layer 100, the core layer 200 and the bottom layer 300 are connected by physical entanglement, chemical cross-linking, adhesive bonding or electrospinning integral molding.

[0047] According to a preferred embodiment, the total thickness of the patch 1, which consists of the surface layer 100, the core layer 200, and the bottom layer 300, is 1-2 mm.

[0048] According to a preferred embodiment, the surface layer 100, the core layer 200 and the bottom layer 300 are all made of biodegradable materials, and the degradation rate of each layer satisfies the following condition: degradation time of bottom layer 300 > degradation time of core layer 200 > degradation time of surface layer 100.

[0049] According to a preferred embodiment, the degradation time of the surface layer 100 is 4-12 weeks, the degradation time of the core layer 200 is 1-2 years, and the degradation time of the bottom layer 300 is 10-15 years. This sequential degradation, tailored to the patient's healing timeline and the needs of different stages, provides stable support and long-lasting anti-adhesion, avoiding discomfort and interference with subsequent diagnosis caused by abnormal adhesion.

[0050] Example 2 Another aspect of the present invention provides a method for preparing a composite layer structure patch 1 for breast reconstruction as described above, comprising the following steps: Step S1: Prepare the surface layer 100 material with intelligent drug controlled release function, the core layer 200 material with shape memory function, and the bottom layer 300 material with anti-adhesion function respectively; Step S2: Composite the three-layer material by lamination, co-extrusion, sequential electrospinning, coating or in-situ polymerization.

[0051] Example 3: A composite layered patch for breast reconstruction A composite layered patch 1 for breast reconstruction comprises, in sequence: a surface layer 100 with drug sustained-release function, a core layer 200 for providing mechanical support, and a bottom layer 300 with an anti-adhesion isolation layer. The surface layer 100 and the bottom layer 300 assist the core layer 200 in providing mechanical support, alleviate adverse reactions after implantation, and improve the overall performance and long-term function of the patch 1.

[0052] Preferably, the intelligent drug-controlled release layer is composed of polycaprolactone (PCL) / gelatin composite nanofibers loaded with magnolol, with a fiber diameter of 200-500 nm. Through the controlled degradation of the PCL / gelatin composite matrix, the continuous release of magnolol is achieved. Utilizing its highly efficient biofilm inhibition capability (inhibition rate ≥90%), it synergistically inhibits cancer cell proliferation and has anti-inflammatory effects, thereby promoting postoperative recovery in patients.

[0053] Preferably, the shape memory support layer is made of polyester polyurethane foam (PUF), and the shape memory support layer has the following properties: Body temperature triggers shape memory (36-37℃). Before implantation, the support layer can be compressed into a sheet-like shape by external force, and after implantation, it returns to the preset breast curvature.

[0054] Preferably, the shape memory support layer is designed with a directionally arranged porous structure, with these channels oriented in a specific direction to conform to the anatomical orientation of the inframammary fold. This structure features high porosity, ranging from 30% to 70%, with pore sizes from 30 to 800 μm. Its compressive modulus is designed to simulate the mechanical behavior of natural mammary glands, thus achieving biomechanical biomimicry.

[0055] This directional porous structure provides a guiding space for cell migration and tissue ingrowth, effectively promoting tissue vascularization. After implantation, it achieves a significantly higher neovascularization density than traditional ADM patches and forms a strong integration interface with surrounding tissues, effectively preventing patch displacement.

[0056] Preferably, the anti-adhesion isolation layer is prepared from a biocompatible polymer substrate through surface modification technology. Its surface has superhydrophilicity and anti-protein non-specific adsorption function, which can significantly reduce protein deposition. This layer also serves as a dense physical barrier, effectively resisting the penetration of cells such as fibroblasts.

[0057] Example 4 In another aspect, the present invention provides the application of a composite layer structure patch 1 for breast reconstruction as described above in the preparation of breast reconstruction.

[0058] During breast reconstruction, such as Figure 2 As shown in the diagram, patch 1 is placed over the implant, with both ends connected to the pectoralis major muscle to form a naturally drooping pocket that accommodates the implant, creating a natural, drooping shape that simulates the actual chest posture. Patch 1, prepared as a repair material, acts as a buffer layer between the implant and body tissues, providing shape support, load-bearing capacity, limiting displacement, relieving inflammation, and inhibiting tumor proliferation, thus protecting the patient during early recovery. Simultaneously, patch 1 gradually biodegrades, not affecting long-term function. Furthermore, it effectively isolates cell adhesion, preventing abnormal adhesion and conformation, reducing the likelihood of implant outline visibility, and preventing capsular contracture. This minimizes disruption to subsequent examinations and daily life comfort for the patient.

[0059] The embodiments described above merely illustrate specific implementation methods of this application, and while the descriptions are detailed and specific, they should not be construed as limiting the scope of protection of this application. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of the technical solution of this application, and these modifications and improvements all fall within the scope of protection of this application.

Claims

1. A composite layered patch for breast reconstruction, characterized in that, The patch comprises a surface layer (100), a core layer (200), and a bottom layer (300); Surface layer (100): Drug controlled release layer, containing drugs, capable of sustained drug release based on condition triggering, maintaining microenvironment stability; Core layer (200): Shape memory support layer, used to provide mechanical support and maintain three-dimensional shape; Bottom layer (300): Anti-adhesion isolation layer, used to prevent cells from adhering to and penetrating the patch.

2. The composite layered patch for breast reconstruction according to claim 1, characterized in that, The specific conditions triggered by the surface layer (100) include one or more of the following: pH response, enzyme response, temperature response, redox response, or degradation response.

3. The composite layered patch for breast reconstruction according to claim 1, characterized in that, The core layer (200) is configured to have a first shape and a second shape, and to be able to switch between the first shape and the second shape under specific conditions.

4. A composite layered patch for breast reconstruction according to claim 3, characterized in that, The first shape can be a compressible shape that facilitates implantation, and the second shape can be an extensible shape that provides mechanical support within the body.

5. A composite layered patch for breast reconstruction according to claim 1, characterized in that, The core layer (200) has a porous structure.

6. A composite layered patch for breast reconstruction according to claim 1, characterized in that, The core layer (200) is made of at least one of the following materials: polycaprolactone, polylactic acid, polyglycolic acid, polylactic acid-glycolic acid copolymer, polyurethane, polydioxanone or polyhydroxy fatty acid ester.

7. A composite layered patch for breast reconstruction according to claim 1, characterized in that, The bottom layer (300) is prepared using a polymer with anti-cell adhesion function or a polymer containing anti-adhesion factors.

8. A composite layered patch for breast reconstruction according to claim 1, characterized in that, The surface layer (100), core layer (200) and bottom layer (300) are all made of biodegradable materials, and the degradation rate of each layer satisfies the following: degradation time of bottom layer (300) > degradation time of core layer (200) > degradation time of surface layer (100).

9. A method for preparing a composite layered patch for breast reconstruction as described in any one of claims 1-8, characterized in that, Includes the following steps: Step S1: Prepare a surface layer (100) material with intelligent drug controlled release function, a core layer (200) material with shape memory function, and a bottom layer (300) material with anti-adhesion function respectively; Step S2: Composite the three-layer material by lamination, co-extrusion, sequential electrospinning, coating or in-situ polymerization.

10. The use of a composite layer structure patch for breast reconstruction as described in any one of claims 1-8 in the preparation of breast reconstruction.

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