CN-121987852-A - Aerogel coating for implant, and preparation method and application thereof

Abstract

The invention provides an aerogel coating for an implant, and a preparation method and application thereof. The coating uses polyvinyl alcohol with the alcoholysis degree of more than 98 percent as a matrix, and the composite bio-based toughening agent and titanium dioxide or carbon nano tube and other functional nano materials are subjected to fluorination/silanization surface hydrophobic modification and chemical crosslinking treatment, and a double drying process combining freeze drying and supercritical carbon dioxide drying is adopted to construct the high-performance coating with the porosity of more than 90 percent and a bionic three-dimensional communicated nano pore structure. The coating can be firmly attached to the surface of a metal implant, keeps structural integrity and stable performance in the long-term implantation process in vivo, has excellent biocompatibility, active antibacterial and antioxidant functions and the capability of remarkably promoting tissue repair and integration, and can effectively solve the key problems of easy falling off, poor in-vivo stability and single biological function of the existing coating.

Inventors

• ZENG ZHUORAN
• LI JUNHONG
• XU SHIWEI
• Jia Lingyi
• ZHANG QIAN
• LI CHUNXUAN
• ZHANG GUIMEI

Assignees

• 湖南大学苏州研究院
• 湖南金箭新材料科技有限公司

Dates

Publication Date

20260508

Application Date

20260206

Claims (8)

1. 1. A method of preparing an aerogel coating for an implant, comprising the steps of: s1, preprocessing the surface of a substrate, namely performing multistage polishing treatment on the implant substrate, removing a surface oxide layer and impurities, and improving the surface roughness; s2, drying the base material, namely, placing the treated base material in an environment with the temperature of 20-30 ℃ and the relative humidity of less than 50 percent; S3, preparing a polyvinyl alcohol solution, namely adding polyvinyl alcohol with the alcoholysis degree of 98% -100% into deionized water, heating to 70-95 ℃, stirring, and preparing a uniform solution with the concentration of 1.0-5.0 g/ml by combining ultrasonic vibration; S4, adding a functional material, namely adding an environment-friendly toughening agent and a functional nano material into the polyvinyl alcohol solution, and uniformly stirring, wherein the toughening agent is selected from natural plant extracts or bio-based polymers, and the functional nano material is selected from at least one of titanium dioxide nano particles and carbon nano tubes; s5, surface modification treatment, namely carrying out fluorination treatment or silanization treatment on the mixed system, and realizing uniform dispersion through an electrostatic spinning technology; s6, crosslinking reaction, namely adding a crosslinking agent, and performing crosslinking reaction at 50-70 ℃, wherein the crosslinking agent is at least one of diethylenetriamine and triaminopropyl triethoxysilane; And S7, drying, namely sequentially performing freeze drying and supercritical carbon dioxide drying to obtain the aerogel coating with the porous structure.
2. 2. The method for preparing an aerogel coating for an implant according to claim 1, wherein in the step S1, the polishing process is performed by using multiple stages of sand paper from coarse to fine.
3. 3. The method for preparing an aerogel coating for an implant according to claim 1, wherein in the step S4, the mass fraction of the toughening agent is 5% -15%, and the mass fraction of the functional nanomaterial is 0.5% -5%.
4. 4. The method for preparing an aerogel coating for an implant according to claim 1, wherein in the step S6, the adding amount of the cross-linking agent is 5% -10% of the total volume of the system.
5. 5. The method for preparing an aerogel coating for an implant according to claim 1, wherein in the step S7, the temperature of freeze-drying is-40 ℃ to-80 ℃.
6. 6. The method of claim 1, wherein the porosity of the aerogel coating obtained in step S7 is not less than 90%.
7. 7. An aerogel coating for an implant, characterized in that it is produced by the production method according to any one of claims 1 to 6.
8. 8. Use of the aerogel coating of claim 7 in the manufacture of an implantable medical device for improving the biocompatibility, structural stability and tissue repair promoting ability of an implant in vivo.

Description

Aerogel coating for implant, and preparation method and application thereof Technical Field The invention belongs to the technical field of new coating materials, and relates to an aerogel coating for an implant, and a preparation method and application thereof. Background Along with the rapid development of biomedical engineering and tissue engineering technology, various implant materials are widely applied in the medical fields of orthopaedics, cardiovascular, soft tissue repair, medicine slow release and the like. Common implants include metal implants (e.g., titanium alloy bone nails, joint prostheses), polymeric stents, composite medical devices, and the like. These implants remain in the body for long periods of time and are in direct contact with biological tissue, the surface properties of which directly affect the biocompatibility, tissue integration and long-term functional stability after implantation. After the implant enters the body, the immune system of the body can respond to foreign materials to trigger phenomena such as inflammatory reaction, fiber wrapping and the like, and the function integration and tissue repair of the implant are affected. To improve interfacial compatibility between the implant and the host tissue, surface coating techniques have become an important modification tool. The implant coating commonly used at present comprises a biological ceramic coating (such as hydroxyapatite), a biodegradable polymer coating (such as polylactic acid and polycaprolactone), a hydrogel coating, various composite functional coatings and the like. The coatings are mainly prepared by adjusting the chemical composition, the morphological structure, the wettability and the like of the surfaces so as to reduce inflammatory reaction and promote cell adhesion and tissue regeneration. However, the prior art coating technology still has the following significant problems in long-term implant applications: 1. the structural compactness contradicts with the material exchange, and the porosity of a plurality of coating materials is low, the structure is compact, and the coating materials can provide a certain mechanical support, but prevent the free diffusion of nutrient substances, oxygen and metabolites, and are not beneficial to cell growth and tissue repair. 2. The long-term stability is insufficient, and part of the high polymer coating is easy to swell, the degradation rate is out of control or the interface is peeled off in vivo, so that the coating functions are prematurely failed, and even local toxic reaction is initiated. 3. The biological function is single, most of the coatings only have basic biocompatibility, and the requirements of complex implantation environments are difficult to meet due to the lack of the multifunctional integration capability of actively regulating and controlling microenvironments, inhibiting inflammation or promoting regeneration. 4. The mechanical property and the structural integrity are poor, particularly in aerogel coatings, although the aerogel coatings have ultrahigh porosity and specific surface area, the problems of low mechanical strength, easiness in collapse in body fluid environment and the like are common, and the application of the aerogel coatings in long-term implantation is limited. In recent years, aerogel materials have shown potential in the fields of tissue engineering and implant device coatings due to their extremely high porosity, low density, controllable pore structure and good biological permeability. The porous structure of the aerogel is beneficial to cell infiltration, vascular ingrowth and substance exchange, and can theoretically provide an ideal bionic microenvironment for tissue repair. However, existing aerogel materials still face a number of technical challenges in implant coating applications. Firstly, aerogel materials generally have the problem of weaker mechanical properties, are easy to collapse in a complex in-vivo environment or attenuate in performance, and are difficult to maintain stable structural forms for a long time. Second, the chemical stability and biosafety of some aerogel materials in the body fluid environment is not sufficient, and adverse biological reactions may be initiated after long-term implantation. Disclosure of Invention The invention aims to provide an aerogel coating for an implant, a preparation method and application thereof, which can be firmly attached to the surface of the implant, stably exist in a body for a long time, have excellent biocompatibility, antibacterial and antioxidant functions and tissue repair and integration promoting functions, and solve the problems of easy falling off, poor stability and single biological function of the existing coating. In order to solve the technical problems, the invention provides a preparation method of an aerogel coating for an implant, which comprises the following steps: s1, preprocessing the surface of a substrate, namely performing multis