Ultrasonic response bionic piezoelectric periosteum and preparation method thereof

Abstract

The invention relates to an ultrasonic response bionic piezoelectric periosteum and a preparation method thereof, and belongs to the technical field of biological materials. According to the present invention, the electrospinning technology is adopted, and a polydopamine (PDA) assisted biomimetic mineralization process is combined to construct the polycaprolactone / zinc oxide (at) polydopamine / hydroxyapatite composite periosteum, such that the polycaprolactone / zinc oxide (at) polydopamine (at) PDA / hydroxyapatite (HA) composite periosteum, which is called PCL / ZnO (at) PDA / HA (PZPH) for short, is constructed; the composite periosteum has a piezoelectric effect, antibacterial activity and a bone-like mineralization structure, and can generate a bioelectrical signal for promoting osteogenesis under the stimulation of low-intensity pulse ultrasound (LIPUS), so that osteogenesis-related cell behaviors are regulated and controlled, and bone repair is promoted. The bionic piezoelectric periosteum prepared by the invention has the characteristics of high porosity, good osseointegration, excellent osteogenic activity and the like, can effectively solve the problems of insufficient biological activity, easy postoperative infection and the like of the existing bone repair material, provides a new solution for the field of bone tissue engineering, and has a good application prospect.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of biological composite materials, in particular to an ultrasonic response biomimetic piezoelectric periosteum and a preparation method thereof. BACKGROUND

[0002] Bone defect is a common orthopedic disease in clinic, which is often caused by trauma, infection, tumor resection or congenital factors. Such defects not only destroy the integrity of the skeleton, but also are more likely to cause local microenvironment disorder due to bacterial infection or body immune disorder, which seriously hinders the bone repair process, and even may progress to osteomyelitis, sepsis and other life-threatening complications.

[0003] At present, the commonly used bone repair materials in clinic have certain effect in providing structural support, but there are still significant limitations in dealing with infection risk, regulating immune response and actively promoting regeneration. Periosteum plays a crucial role in bone regeneration: it not only maintains the homeostasis of the skeleton, but also is the source of more than 90% of new bone in the early repair stage. Therefore, constructing a functional artificial periosteum is considered as a key strategy for repairing bone defects.

[0004] How to construct a multifunctional integrated biomimetic periosteum with good mechanical support, long-term antibacterial activity, excellent bone integration ability, and the ability to respond to external ultrasonic stimulation and actively generate pro-osteogenic bioelectric signals through a simple and controllable process is still an important challenge in the field of bone tissue engineering. SUMMARY

[0005] In view of the problems of insufficient biological activity, limited bone integration ability and postoperative infection of the prior art, the present application provides an ultrasonic response biomimetic piezoelectric PZPH periosteum and a preparation method thereof. The periosteum prepared by the method of the present application has excellent electrical properties, and can form a hydroxyapatite coating on its surface through biomimetic mineralization, thereby having good bone integration and bone induction, and can be used as an ideal scaffold material for bone defect repair. The electrospun nanofiber periosteum has good application potential in the field of bone tissue engineering and is expected to be used for the regeneration and repair of clinical bone defects.

[0006] In order to achieve the above-mentioned application purposes, the present application provides the following technical solutions.

[0007] The present application discloses an ultrasonic response biomimetic piezoelectric periosteum, characterized in that the periosteum is a PZPH composite scaffold composed of polycaprolactone, zinc oxide nanoparticles, polydopamine coating and hydroxyapatite coating, and is prepared by electrospinning combined with a biomimetic mineralization process.

[0008] Further, the biomimetic piezoelectric periosteum has a three-dimensional porous network fiber structure, and the average diameter of the fibers is 150 nm to 410 nm.

[0009] The application also discloses application of the biomimetic piezoelectric bone membrane in preparation of a product for promoting proliferation of bone marrow mesenchymal stem cells.

[0010] The application also discloses application of the biomimetic piezoelectric bone membrane in preparation of a product for promoting proliferation of bone marrow mesenchymal stem cells.

[0011] The application also discloses application of the biomimetic piezoelectric bone membrane in preparation of a product for promoting proliferation of bone marrow mesenchymal stem cells.

[0012] The application also discloses a preparation method of the ultrasonic response biomimetic piezoelectric bone membrane. S1. PCL and ZnO are dissolved in hexafluoroisopropanol to prepare an electrostatic spinning solution, and a PCL / ZnO nanofiber membrane is prepared through an electrostatic spinning technology; S2. The PCL / ZnO nanofiber membrane is immersed in a dopamine hydrochloride solution and is subjected to first water bath ultrasonic treatment, so that a PDA coating layer is formed on the surface of the PCL / ZnO nanofiber membrane; S3. The composite material with the PDA coating layer obtained in step S2 is immersed in a HA aqueous solution and is subjected to second water bath ultrasonic treatment to complete biomimetic mineralization, so that a PZPH composite scaffold is prepared.

[0013] Further, in step S1, the mass ratio of ZnO to PCL is 0:100 or 1:99, and the amount of hexafluoroisopropanol is 5 mL; the electrostatic spinning process parameters include that the spinning voltage is 15 kV, the solution propelling rate is 0.8 mL / h, and the receiving distance is 15 cm.

[0014] Further, in step S2, the dopamine concentration is 2 mg / mL, and the buffer pH is 8.5.

[0015] Further, in step S3, the HA suspension concentration is 5 mg / mL.

[0016] Further, the application of the biomimetic piezoelectric bone membrane prepared by the preparation method to preparation of a medical biomaterial for bone defect repair is disclosed.

[0017] Compared with the prior art, the application has the following beneficial effects: 1. The process is simple and the performance is excellent: the process combining electrostatic spinning and biomimetic mineralization can be used to prepare the PZPH composite bone membrane with good piezoelectric performance, mechanical strength and hydrophilicity, the preparation process is clear, the conditions are easy to control, and the process has good repeatability and generalizability; 2. Good biocompatibility: the PCL, ZnO, PDA and HA materials used in the application have good biocompatibility and can be degraded or metabolized in vivo, and are safe. 3. Multifunctional synergistic integration: the periosteum not only can provide the necessary mechanical support and physical barrier effect, but also has comprehensive biological functions such as antibacterial and anti-inflammatory, promoting cell adhesion and proliferation, inducing osteogenic differentiation and promoting bone regeneration; 4. Good application prospect: the PZPH periosteum provided by the application can be used for the preparation of medical biomaterials related to bone defect repair, and has good application potential in the field of bone tissue engineering and tissue regeneration.

[0018] The above is a summary of the technical solutions of the present application and its beneficial effects. In order to make the technical means, objectives, characteristics and advantages of the present application more clear, the present application will be further described below in combination with the drawings and specific examples, so that those skilled in the art can understand and implement the present application. BRIEF DESCRIPTION OF DRAWINGS

[0019] Figure 1 The above is a summary of the technical solutions of the present application and its beneficial effects. In order to make the technical means, objectives, characteristics and advantages of the present application more clear, the present application will be further described below in combination with the drawings and specific examples, so that those skilled in the art can understand and implement the present application.

[0020] Figure 2 The above is a summary of the technical solutions of the present application and its beneficial effects. In order to make the technical means, objectives, characteristics and advantages of the present application more clear, the present application will be further described below in combination with the drawings and specific examples, so that those skilled in the art can understand and implement the present application.

[0021] Figure 3 The above is a summary of the technical solutions of the present application and its beneficial effects. In order to make the technical means, objectives, characteristics and advantages of the present application more clear, the present application will be further described below in combination with the drawings and specific examples, so that those skilled in the art can understand and implement the present application.

[0022] Figure 4 The above is a summary of the technical solutions of the present application and its beneficial effects. In order to make the technical means, objectives, characteristics and advantages of the present application more clear, the present application will be further described below in combination with the drawings and specific examples, so that those skilled in the art can understand and implement the present application.

[0023] Figure 5 The above is a summary of the technical solutions of the present application and its beneficial effects. In order to make the technical means, objectives, characteristics and advantages of the present application more clear, the present application will be further described below in combination with the drawings and specific examples, so that those skilled in the art can understand and implement the present application.

[0024] Figure 6 The above is a summary of the technical solutions of the present application and its beneficial effects. In order to make the technical means, objectives, characteristics and advantages of the present application more clear, the present application will be further described below in combination with the drawings and specific examples, so that those skilled in the art can understand and implement the present application.

[0025] Figure 7 The above is a summary of the technical solutions of the present application and its beneficial effects. In order to make the technical means, objectives, characteristics and advantages of the present application more clear, the present application will be further described below in combination with the drawings and specific examples, so that those skilled in the art can understand and implement the present application. DETAILED DESCRIPTION

[0026] The present application will be further described below in combination with specific examples. However, it should not be understood that the above-mentioned subject matter of the present application is limited to the following examples, and any technology implemented based on the content of the present application falls within the scope of the present application.

[0027] Unless otherwise specified, the reagents and materials used in the present application are commercially available.

[0028] Example 1: Preparation and performance characterization of ultrasonic response biomimetic piezoelectric periosteum (PZPH).

[0029] I. Experimental materials and methods.

[0030] S1. Preparation of PCL / ZnO (PZ) nanofiber membrane.

[0031] ZnO (Araldite, China) and PCL (Araldite, China) were mixed at a mass ratio of 0:100 or 1:99, and then dissolved in hexafluoroisopropanol (HFIP, Shanghai Maikelin Biochemical Technology Co., Ltd.) to obtain a uniform electrospinning solution. The electrospinning solution was ultrasonically dispersed for 60 min, and then magnetically stirred for 24 h. Then, 5 mL of the electrospinning solution was taken and electrospun under the following conditions: a spinning voltage of 15.0 kV, a solution advancing rate of 0.8 mL / h, and a receiving distance of 15 cm. The electrospinning was continued for 20 h to obtain a PCL / ZnO (PZ) nanofiber membrane.

[0032] S2. Construction of PDA coating on the surface of PZ nanofiber membrane A Tris-HCl buffer solution with a pH of 8.5 was prepared, and hydrochloric acid dopamine was added to make the dopamine concentration 2 mg / mL. The PZ nanofiber membrane obtained in step S1 was immersed in the hydrochloric acid dopamine solution and reacted under water bath ultrasonic conditions for 1 h to form a PDA coating on its surface, thereby obtaining a PCL / ZnO / PDA composite material.

[0033] S3. Preparation of PZPH composite scaffold by biomimetic mineralization.

[0034] Nanometer HA was dispersed in deionized water at a concentration of 5 mg / mL, and ultrasonically dispersed for 6 h to obtain a uniform HA suspension. The PCL / ZnO / PDA composite material obtained in step S2 was immersed in the HA suspension and treated under water bath ultrasonic conditions for 60 min (or 60 min, 90 min) to complete the biomimetic mineralization process, thereby obtaining a PCL / ZnO / PDA / HA (PZPH) composite scaffold. The obtained sample was vacuum dried and sealed for storage.

[0035] II. Performance characterization.

[0036] Piezoelectric performance test. PCL, PZ and PZPH periosteum were cut into circular pieces with a diameter of about 1.6 cm. A linear motor was used to apply a cyclic pressure to the sample (a load of 25 N and a frequency of 1 Hz), and the voltage / charge output signal of the sample was recorded by an oscilloscope and an electrometer, respectively, to evaluate the piezoelectric response performance.

[0037] III. Experimental results.

[0038] As Figure 1As shown, all groups of nanofibers formed a uniform, interconnected three-dimensional porous network structure. Uniform polymerization of polydopamine on the fiber surface could be achieved within one hour using an ultrasonic-assisted method. This process maintained the original three-dimensional structure of the fiber while allowing precise control of the surface coating thickness by adjusting the mineralization time of hydroxyapatite. With prolonged reaction time, the fiber surface was gradually densely covered by in-situ generated HA nanoparticles.

[0039] like Figure 2 As shown, statistical analysis of fiber diameter reveals that the average diameters of PCL, PZ, and PZPH are 410.14 ± 14.69 nm, 150.48 ± 1.05 nm, and 160.38 ± 1.99 nm, respectively. The diameters of PZ and PZPH fibers are significantly smaller than those of pure PCL fibers. This is mainly attributed to the introduction of ZnO nanoparticles, which improves the conductivity of the spinning solution, thereby generating stronger tensile forces in a high-voltage electric field, leading to fiber refinement.

[0040] like Figure 3 As shown, compared with pure PCL membranes, the tensile strength of PZ and PZPH nanofiber membranes increased by 24.04% and 43.23%, respectively, and the Young's modulus also increased significantly by 14.78% and 20.80%, respectively. This indicates that the introduction of ZnO nanoparticles and HA coating together enhances the mechanical properties of the composite material.

[0041] like Figure 4 As shown, the contact angle test results of PCL, PZ and PZPH are 140.89 ± 1.17°, 56.91 ± 2.17° and 32.57 ± 1.83°, respectively, indicating that the hydrophilicity of the material surface is significantly and gradually improved from PCL to PZPH.

[0042] like Figure 5 As shown, after the introduction of ZnO nanoparticles, the piezoelectric output of the PZPH scaffold in terms of voltage, current and transferred charge is significantly higher than that of the pure PCL group, and the mineralization treatment has no significant negative impact on its piezoelectric properties.

[0043] like Figure 6 As shown, after culturing under ultrasound stimulation for 7 days, the proliferation rate of BMSCs in the PZPH group and the PZPH+US group increased by 13.49% and 28.95% respectively compared with the pure PCL group, indicating that the composite material has good biocompatibility and cell proliferation promotion ability.

[0044] like Figure 7 As shown, compared with the PCL group, the alkaline phosphatase activity of each experimental group was increased to varying degrees. Among them, the PZPH+US group had the highest ALP activity after 14 days of culture, which was 75.12% higher than that of the PCL group, showing excellent potential to promote osteodifferentiation.

[0045] The above description is only the preferred embodiment of the present application, and is not used to limit the patent scope of the present application. For those skilled in the art, the present application can have various changes and modifications. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present application shall be included in the protection scope of the present application.

Claims

1. An ultrasound-responsive biomimetic piezoelectric bone membrane, characterized in that, The periosteum is a PZPH composite scaffold, composed of PCL, ZnO nanoparticles, PDA coating and HA coating, and is prepared by electrospinning combined with a biomimetic mineralization process.

2. The biomimetic piezoelectric bone membrane according to claim 1, characterized in that, The biomimetic piezoelectric bone membrane has a three-dimensional porous mesh fiber structure with an average fiber diameter of 150 nm to 410 nm.

3. An application of the ultrasound-responsive biomimetic piezoelectric periosteum as described in any one of claims 1 to 2, characterized in that, Used to prepare materials for bone defect repair.

4. An application of the ultrasound-responsive biomimetic piezoelectric periosteum as described in any one of claims 1 to 2, characterized in that, Used to prepare products that promote the proliferation of bone marrow mesenchymal stem cells.

5. An application of the ultrasound-responsive biomimetic piezoelectric periosteum as described in any one of claims 1 to 2, characterized in that, Used to prepare products that promote osteogenic differentiation of bone marrow mesenchymal stem cells.

6. A method for preparing an ultrasound-responsive biomimetic piezoelectric bone membrane as described in any one of claims 1 to 2, characterized in that, Includes the following steps: S1. PCL and ZnO were dissolved together in hexafluoroisopropanol to prepare an electrospinning solution, and then PCL / ZnO nanofiber membranes were prepared by electrospinning technology. S2. The PCL / ZnO nanofiber membrane is immersed in a dopamine hydrochloride solution and subjected to a first water bath ultrasonic treatment to form a PDA coating on its surface; S3. The PDA-coated composite material obtained in step S2 is immersed in an aqueous HA solution and subjected to a second water bath ultrasonic treatment to complete biomimetic mineralization, thereby obtaining the PZPH composite scaffold.

7. The preparation method according to claim 6, characterized in that, In step S1, the mass ratio of ZnO to PCL is 0:100 or 1:99; the electrospinning process parameters include: spinning voltage of 15 kV, solution feed rate of 0.8 mL / h, and receiving distance of 15 cm.

8. The preparation method according to claim 6, characterized in that, In step S2, the dopamine concentration was 2 mg / mL and the buffer pH was 8.

5.

9. The preparation method according to claim 6, characterized in that, In step S3, the concentration of the HA suspension is 5 mg / mL.

10. An application of a biomimetic piezoelectric bone membrane prepared by the preparation method according to any one of claims 6 to 9, characterized in that, Used to prepare medical biomaterials for bone defect repair.

Images