Biological adhesive for ultrasonic printing as well as preparation and application of biological adhesive

Abstract

The invention belongs to the technical field of biological materials and ultrasonic printing, and particularly discloses a biological adhesive for ultrasonic printing and preparation and application thereof. The biological adhesive comprises a heat-sensitive main body material and a chemical adhesion component, the heat-sensitive main body material comprises hydroxybutyl chitosan, and the chemical adhesion component comprises polyacrylic acid-N-hydroxysuccinimide ester. The bioadhesive has excellent ultrasonic responsiveness, formability and bioadhesion performance, directional deposition, in-situ solidification and tissue surface adhesion can be achieved in a non-contact and accurately-controlled ultrasonic printing system, and the bioadhesive is suitable for various biomedical scenes such as tissue repair, minimally invasive medicine, biological device construction and drug delivery interface printing.

Description

Technical Field

[0001] This application relates to the fields of biomaterials and ultrasonic printing technology, and in particular to a bioadhesive for ultrasonic printing and its preparation and application. Background Technology

[0002] In recent years, with the increasing demand for non-invasive biomanufacturing and precise tissue repair, achieving precise deposition and in-situ curing of materials in wetting and biological tissue environments has become a key challenge in tissue engineering, bioprinting, and minimally invasive medicine. Traditional printing methods based on inkjet, extrusion, or photopolymerization are often limited by problems such as poor energy transfer in complex environments, strong material incompatibility, and difficulties in real-time curing. Therefore, developing a biomaterial system that can be remotely energy controlled, is injectable, can be cured in situ, and possesses good bioadhesion properties is of great significance. Ultrasonic printing, as an emerging contactless manufacturing method, utilizes focused ultrasound to precisely deposit energy in space, inducing droplet focusing, localized temperature rise, or microflow effects, thereby enabling the directional driving, shaping, or solidification of liquid biomaterials. Especially on tissue surfaces or in vivo environments, the acoustic-thermal effect generated by focused ultrasound provides an ideal excitation mechanism for heat-sensitive materials.

[0003] However, traditional bio-hydrogels or tissue adhesives (such as PEGDA systems that rely on UV curing and gelatin-based systems that require exogenous crosslinking agents) mostly rely on UV, chemical crosslinking, or exogenous temperature control methods for gelation, making them difficult to meet the requirements of rapid gelation and stable adhesion in vivo or humid environments. Furthermore, existing bio-adhesives lack responsiveness under ultrasonic fields, preventing the continuous integrated operation of "printing-curing-adhesion," thus limiting their application in non-invasive tissue repair, in-situ drug delivery, and minimally invasive construction.

[0004] Therefore, there is currently a lack of a composite material system that combines thermo-curing, ultrasonic responsiveness, and tissue adhesion, which can be directly adapted to ultrasonic printing scenarios to achieve in vivo or in-situ construction operations. Thus, there is an urgent need to develop a new type of bioadhesive material that can complete phase transformation into gel under acoustic and thermal drive and simultaneously establish a stable chemical bond with the tissue interface, in order to fill the current gap in the integrated material construction technology of "printing-curing-adhesion" in complex environments. Summary of the Invention

[0005] In view of the shortcomings of the prior art described above, the purpose of this application is to provide a bioadhesive for ultrasonic printing, its preparation and application, to solve the problem that the bioadhesive in the prior art cannot achieve rapid curing and stable bioadhesion in the ultrasonic printing environment.

[0006] To achieve the above and other related objectives, this application provides a bioadhesive for ultrasonic printing, comprising a heat-sensitive host material and a chemical adhesive component, wherein the heat-sensitive host material comprises hydroxybutyl chitosan (HBCS) and the chemical adhesive component comprises poly(N-hydroxysuccinimide) acrylate (PAA-NHS).

[0007] Furthermore, the bioadhesive is a sol at room temperature.

[0008] Furthermore, the bioadhesive transforms from a sol phase to a gel under acoustic-thermal excitation, automatically solidifies, and covalently adheres to the interface of biological tissues. Here, acoustic-thermal excitation refers to the acoustic-thermal effect generated by focused ultrasound.

[0009] Furthermore, in the bioadhesive, the mass ratio of hydroxybutyl chitosan to poly(N-hydroxysuccinimide acrylate) is 10~12:1.

[0010] Furthermore, the concentration of hydroxybutyl chitosan in the bioadhesive is 0.05~0.06 g / mL.

[0011] Furthermore, the bioadhesive also includes a dispersion medium selected from water.

[0012] Furthermore, the pH of the bioadhesive is 5.5 to 6.5.

[0013] Furthermore, the storage temperature of the bio-adhesive is 4~10°C.

[0014] Furthermore, the bioadhesive is prepared by adding poly(N-hydroxysuccinimide) acrylate to a hydroxybutyl chitosan solution and stirring; preferably, the bioadhesive is prepared by adding poly(N-hydroxysuccinimide) acrylate to a hydroxybutyl chitosan solution and stirring at 4-10°C; the hydroxybutyl chitosan solution is preferably an aqueous solution of hydroxybutyl chitosan.

[0015] This application also provides a method for preparing a bioadhesive for ultrasonic printing, comprising the following steps: adding polyacrylic acid-N-hydroxysuccinimide ester to a hydroxybutyl chitosan solution and stirring to prepare the bioadhesive.

[0016] Further, at 4~10°C, polyacrylic acid-N-hydroxysuccinimide ester was added to a hydroxybutyl chitosan solution and stirred to prepare the bioadhesive.

[0017] Further, hydroxybutyl chitosan is added to cold water and stirred at 4-10°C to obtain the hydroxybutyl chitosan solution.

[0018] Furthermore, the mass ratio of hydroxybutyl chitosan to poly(N-hydroxysuccinimide acrylate) is 10~12:1.

[0019] Furthermore, in the hydroxybutyl chitosan solution, the concentration of hydroxybutyl chitosan is 0.05~0.06 g / mL.

[0020] Furthermore, during the preparation of the bioadhesive, the pH of the system is controlled to be 5.5~6.5.

[0021] This application also provides the use of the bioadhesives described above in the preparation of medical devices, medical materials or pharmaceuticals for non-invasive tissue repair, in-situ drug delivery, minimally invasive medicine and / or the construction of biodevices.

[0022] As described above, the beneficial effects of the bioadhesive for ultrasonic printing, its preparation, and its application in this application are as follows: (1) Acoustic and thermal response curing: Relying on the thermal sensitivity of HBCS, this system can achieve spatial localization and time-controllable in-situ gelation through the acoustic and thermal effect generated by ultrasonic focusing, avoiding the invasion of tissues by traditional photocuring or chemical cross-linking.

[0023] (2) Covalent adhesion at tissue interface: PAA-NHS components can undergo rapid amidation reaction with primary amines on tissue surface to form a stable chemical bond, achieving high-strength, wash-resistant bioadhesion.

[0024] (3) Strong printing adaptability: The material can be stored at low temperature, flow at room temperature, and triggered by sound. It is suitable for high-precision droplet or surface scanning ultrasonic printing platforms. During the printing process, it can realize the integrated operation of automatic "deposition + solidification + adhesion".

[0025] (4) Good biocompatibility and degradability: HBCS is a natural source material, and PAA-NHS is converted into stable amide bonds after the reaction. The overall system is low in toxicity and degradable, and is suitable for in vivo application scenarios. (5) Breaking through traditional limitations: Compared with the PEGDA system that relies on UV curing or the gelatin-based system that requires exogenous crosslinking agents, the bioadhesive of this application does not require an additional energy source or chemical crosslinking agent. It can complete printing and tissue anchoring by ultrasound alone, which significantly improves in vivo adaptability and ease of operation.

[0026] In summary, the bioadhesive provided in this application has excellent ultrasonic responsiveness, formability and bioadhesion properties, and can achieve directional deposition, in-situ curing and tissue surface adhesion in a contactless and precisely controlled ultrasonic printing system. It is suitable for a variety of biomedical scenarios such as tissue repair, minimally invasive medicine, biodevice construction and drug delivery interface printing. Detailed Implementation

[0027] The following specific examples illustrate the implementation of this application. Those skilled in the art can easily understand other advantages and effects of this application from the content disclosed in this specification. This application can also be implemented or applied through other different specific embodiments. Various details in this specification can also be modified or changed based on different viewpoints and applications without departing from the spirit of this application. In the absence of conflict, the following embodiments and features in the embodiments can be combined with each other.

[0028] In this application, unless otherwise stated, the term "multiple" means two or more.

[0029] The character " / " indicates that the objects before and after it are in an "or" relationship. For example, A / B means: A or B.

[0030] The term "and / or" describes an association between objects, indicating that three relationships can exist. For example, A and / or B means: A or B, or A and B.

[0031] In the following embodiments, hydroxybutyl chitosan and poly(N-hydroxysuccinimide) acrylate can be prepared in-house or purchased from commercial sources.

[0032] One embodiment of this application provides a bioadhesive for ultrasonic printing, which is a two-component composite system including a heat-sensitive host material and a chemical adhesive component. The heat-sensitive host material includes hydroxybutyl chitosan, and the chemical adhesive component includes poly(N-hydroxysuccinimide) acrylate.

[0033] HBCS is a naturally derived polysaccharide with thermally responsive phase transition behavior. Its aqueous solution can achieve a reversible sol-gel transition at about 37~40°C. It has good injectability, biocompatibility and gelling properties, making it very suitable for the development of injectable hydrogels and tissue repair materials.

[0034] PAA-NHS is a bioadhesive monomer with an active ester structure that can undergo covalent amidation with primary amine (-NH2) groups in tissue surface proteins, thereby achieving strong and rapid tissue adhesion. This covalent adhesion mechanism is particularly suitable for constructing aquatic bioadhesives that are resistant to liquid erosion and exhibit strong adhesion.

[0035] Therefore, due to the excellent sol-gel phase transition capability of HBCS, the bioadhesive of this application can achieve rapid gelation under body temperature or acoustic-thermal excitation. Simultaneously, because PAA-NHS possesses the ability to undergo amidation reactions with primary amines on tissue surfaces, it endows the bioadhesive of this application with excellent covalent adhesion properties. Moreover, since HBCS is a naturally derived material, PAA-NHS transforms into stable amide bonds after the reaction, resulting in a low-toxicity and biodegradable overall system. Therefore, the bioadhesive of this application exhibits good biocompatibility and degradability, making it suitable for in vivo applications. Furthermore, the bioadhesive of this application requires no additional energy source or chemical crosslinking agent; printing and tissue anchoring can be completed solely through ultrasound, avoiding the invasiveness to tissues caused by traditional photocuring or chemical crosslinking, significantly improving in vivo adaptability and ease of operation.

[0036] In one embodiment of this application, the bioadhesive is prepared by adding PAA-NHS to an HBCS solution and stirring. At room temperature, it is a sol, which transforms into a gel under acoustic-thermal excitation, automatically solidifies, and covalently adheres to the interface of biological tissue. The acoustic-thermal excitation refers to the acoustic-thermal effect generated by focused ultrasound. The bioadhesive of this application features room-temperature flow and acoustic triggering, enabling automated "deposition + solidification + adhesion" in an integrated process during ultrasonic printing, exhibiting strong printability. Specifically, the bioadhesive is loaded as printing ink into an ultrasonic printing device (e.g., a high-precision droplet or surface-scanning ultrasonic printing platform). By focusing ultrasound to form a local acoustic-thermal region (temperature rise of approximately 38-45°C), rapid gelation of HBCS is induced. Simultaneously, PAA-NHS undergoes a covalent reaction with amino groups on the tissue surface, achieving a synchronous "solidification + adhesion" process. In one embodiment of this application, the mass ratio of HBCS to PAA-NHS in the bioadhesive is 10~12:1, and the concentration of HBCS is 0.05~0.06g / mL.

[0037] In one embodiment of this application, the bioadhesive further includes a dispersion medium selected from water. The water includes, but is not limited to, distilled water, ultrapure water, etc.

[0038] In one embodiment of this application, the pH of the bioadhesive is 5.5-6.5, the purpose of which is to prevent the hydrolysis of N-hydroxysuccinimide ester (NHS). The pH of the bioadhesive can be adjusted using a buffer such as PBS, and the pH of the PBS buffer is preferably 5.8.

[0039] In one embodiment of this application, the bioadhesive can be prepared fresh or in advance for later use. It can be stored at low temperatures, for example, 4~10°C, at which temperature it can be refrigerated for 5~7 days. Before use, it should be warmed to room temperature to maintain good fluidity. In addition, it can be pre-concentrated or its rheology adjusted according to the needs of ultrasonic printing to obtain a printable composite system.

[0040] In one embodiment of this application, the bioadhesive is prepared by adding PAA-NHS to an HBCS solution and stirring; preferably, the bioadhesive is prepared by adding PAA-NHS to an HBCS solution and stirring at 4-10°C; the HBCS solution... Another embodiment of this application provides a method for preparing a bioadhesive for ultrasonic printing as described in the embodiments / examples, comprising the following steps: adding PAA-NHS to an HBCS solution and stirring to prepare the bioadhesive. The preferred mass ratio of HBCS to PAA-NHS is 10~12:1; the pH of the system is controlled within the range of 5.5~6.5, and a buffer solution, such as PBS buffer, can be used to adjust the pH.

[0041] The bioadhesive of this application is obtained by mixing and assembling PAA-NHS in an HBCS solution, a process that needs to be carried out at low temperature (e.g., 4-10°C). Therefore, in one embodiment of this application, PAA-NHS is added to an HBCS solution at 4-10°C and stirred to prepare the bioadhesive.

[0042] Furthermore, the HBCS solution is preferably an aqueous solution of HBCS with a concentration of 0.05~0.06 g / mL, prepared by adding HBCS powder to water, and the preparation process also needs to be carried out under low temperature conditions (e.g., 4~10°C). Therefore, in one embodiment of this application, HBCS is added to cold water and stirred at 4~10°C to obtain the HBCS solution.

[0043] Another embodiment of this application provides the use of the bioadhesive described above in the preparation of medical devices, medical materials, or pharmaceuticals for non-invasive tissue repair, minimally invasive medicine, and / or the construction of biodevices.

[0044] One embodiment of this application describes the preparation of a bioadhesive for ultrasonic printing, which is then used to repair wound defects in mice. The specific implementation process is as follows: S1. Preparation of HBCS solution: Weigh 5.5g of HBCS powder and dissolve it in 100mL of cold distilled water (4°C). Place the solution in an ice bath until a clear, homogeneous heat-sensitive polymer solution is formed. This solution is denoted as solution A. S2, Composite Assembly: Under low temperature conditions (4~10°C), PAA-NHS is added dropwise to solution A at a volume ratio of approximately 1:20. 5 mg of PAA-NHS is added dropwise to 1 mL of solution A while gently stirring for 10 minutes to obtain a composite solution. This compound solution can be stored at 4°C for 5-7 days. Before use, it should be warmed to room temperature to maintain good fluidity. S3. The bio-adhesive (i.e., composite solution) prepared in S2 is brought back to room temperature to maintain good fluidity and added to the ultrasonic printing equipment as printing ink. The printing ink is injected into the mouse wound defect and cured by focused ultrasound, successfully repairing the mouse wound defect.

[0045] The above embodiments are merely illustrative of the principles and effects of this application and are not intended to limit this application. Any person skilled in the art can modify or alter the above embodiments without departing from the spirit and scope of this application. Therefore, all equivalent modifications or alterations made by those skilled in the art without departing from the spirit and technical concept disclosed in this application should still be covered by the claims of this application.

Claims

1. A bioadhesive for ultrasonic printing, characterized in that, It includes a heat-sensitive host material and a chemical adhesive component, wherein the heat-sensitive host material includes hydroxybutyl chitosan and the chemical adhesive component includes poly(N-hydroxysuccinimide) acrylate.

2. The bioadhesive according to claim 1, characterized in that: The bioadhesive is a sol at room temperature.

3. The bioadhesive according to claim 2, characterized in that: The bioadhesive changes from a sol phase to a gel under acoustic-thermal excitation, solidifies automatically, and covalently adheres to the interface of biological tissues.

4. The bioadhesive according to any one of claims 1 to 3, characterized in that: In the bioadhesive, the mass ratio of hydroxybutyl chitosan to poly(N-hydroxysuccinimide acrylate) is 10~12:

1.

5. The bioadhesive according to claim 4, characterized in that: The concentration of hydroxybutyl chitosan in the bioadhesive is 0.05~0.06 g / mL.

6. The bioadhesive according to claim 1, characterized in that: The bioadhesive also includes a dispersion medium selected from water; And / or, the pH of the bioadhesive is 5.5 to 6.5; And / or, the storage temperature of the bioadhesive is 4~10°C; And / or, the bioadhesive is prepared by stirring poly(N-hydroxysuccinimide) acrylate in a hydroxybutyl chitosan solution.

7. A method for preparing a bioadhesive for ultrasonic printing, characterized in that, The process includes the following steps: adding polyacrylic acid-N-hydroxysuccinimide ester to a hydroxybutyl chitosan solution and stirring to prepare the bioadhesive.

8. The preparation method according to claim 7, characterized in that: The bioadhesive was prepared by adding polyacrylic acid-N-hydroxysuccinimide ester to a hydroxybutyl chitosan solution and stirring at 4~10°C. And / or, add hydroxybutyl chitosan to cold water and stir at 4~10°C to obtain the hydroxybutyl chitosan solution.

9. The preparation method according to claim 7 or 8, characterized in that: The mass ratio of hydroxybutyl chitosan to poly(N-hydroxysuccinimide acrylate) is 10~12:1; And / or, in the hydroxybutyl chitosan solution, the concentration of hydroxybutyl chitosan is 0.05~0.06 g / mL; And / or, during the preparation of the bioadhesive, the pH of the system is controlled to be 5.5~6.

5.

10. The use of the bioadhesive for ultrasonic printing according to any one of claims 1 to 6 and / or the bioadhesive for ultrasonic printing prepared by the method according to any one of claims 7 to 8 in the preparation of medical devices, medical materials or drugs for non-invasive tissue repair, in-situ drug delivery, minimally invasive medicine and / or the construction of bio-devices.