CN-117339009-B - DFO@GMs-pDA/PN composite stent for promoting vascularization and bone formation as well as preparation method and application thereof

Abstract

The invention belongs to the technical fields of biomedical materials and biomedical engineering, and discloses a DFO@GMs-pDA/PN composite scaffold for promoting vascularization and bone formation, and a preparation method and application thereof. According to the invention, by utilizing the electrostatic spinning, pDA modification and emulsification-extraction technology, DFO is wrapped in GMs and is loaded in a PN electrospun membrane modified by the pDA surface, so that the DFO@GMs-pDA/PN composite scaffold capable of promoting vascularized bone regeneration is constructed. Wherein, the surface DFO@GMs begins to disintegrate and release DFO after implantation and reaches the maximum drug release rate after 48 hours, thereby promoting the growth of new blood vessels, the recruitment of stem cells and the secretion and presentation of related factors in early stage of bone regeneration and providing an important blood supply basis for bone regeneration.

Inventors

• ZHAO LIXING
• Wang Raokaijuan
• CHEN ROUZHEN
• ZHOU HONGLING

Assignees

• 四川大学

Dates

Publication Date

20260508

Application Date

20231019

Claims (9)

1. 1. The preparation method of the DFO@GMs-pDA/PN composite stent for promoting vascularization and bone formation is characterized by comprising the following steps of: (1) Preparing a PN bracket main body, namely mixing nano clay, polycaprolactone and an electrospinning solvent to obtain a mixed solution, and carrying out electrostatic spinning on the mixed solution to obtain the PN bracket main body; (2) The preparation of the polydopamine modified PN stent main body comprises the steps of mixing dopamine powder and a tris buffer solution to obtain a mixed solution, immersing the PN stent main body into the mixed solution for reaction to obtain the polydopamine modified PN stent main body; (3) The preparation method of the DFO@GMs comprises the steps of mixing gelatin, deferoxamine and water to obtain solution A, mixing mineral oil and Span-80 to obtain solution B, and carrying out cross-linking reaction on the solution A, the solution B and glutaraldehyde to obtain the DFO@GMs; (4) The preparation method of the DFO@GMs-pDA/PN composite stent comprises the steps of mixing the DFO@GMs, ethanol and phosphate buffer salt solution to obtain a mixed solution, and immersing a polydopamine modified PN stent main body into the mixed solution for reaction to obtain the DFO@GMs-pDA/PN composite stent.
2. 2. The method for preparing the DFO@GMs-pDA/PN composite scaffold for promoting vascularization and bone formation according to claim 1, wherein in the step (1), an electrospinning solvent comprises N, N-dimethylformamide and dichloromethane, the mass ratio of the N, N-dimethylformamide to the dichloromethane is 3-4:1, and the mass ratio of the nanoclay to the polycaprolactone to the electrospinning solvent is 0.12-0.15:1.5-2.5:8-10.
3. 3. The method for preparing the DFO@GMs-pDA/PN composite scaffold for promoting vascularization and bone formation according to claim 2, wherein in the step (1), the mixing temperature is 55-65 ℃, the mixing stirring rate is 100-200 r/min, and the mixing time is 50-60 min.
4. 4. The method for preparing the DFO@GMs-pDA/PN composite stent for promoting vascularization and bone formation according to any one of claims 1-3, wherein in the step (1), parameters of electrostatic spinning are set as follows, a positive voltage is 11.5-12.5 kV, a negative voltage is 2.3-2.6 kV, a pushing speed is 0.14-0.16 mm/min, a receiving distance is 8-12 cm, a receiving speed is 30-35 r/min, and a receiving time is 2.5-3 h.
5. 5. The method for preparing the DFO@GMs-pDA/PN composite scaffold for promoting vascularization and bone formation according to claim 4, wherein in the step (2), the mass ratio of the dopamine powder to the tris (hydroxymethyl) aminomethane in the tris buffer solution is 0.2:0.11-0.12, the reaction time is 10-14 h, and the stirring rate of the reaction is 200-250 r/min.
6. 6. The method for preparing the DFO@GMs-pDA/PN composite scaffold for promoting vascularization and bone formation according to claim 5, wherein in the step (3), the mass volume ratio of gelatin, deferoxamine and water is 2-3 g:0.01-0.02 g:20-25 mL, the volume ratio of mineral oil and Span-80 is 45-50:1, the volume ratio of Span-80 and glutaraldehyde is 2:0.03-0.05, and the volume fraction of glutaraldehyde is 45-50%.
7. 7. The method for preparing the DFO@GMs-pDA/PN composite scaffold for promoting vascularization and bone formation according to claim 6, wherein in the step (3), the temperature of the crosslinking reaction is 3-4 ℃, and the time of the crosslinking reaction is 20-30 min.
8. 8. The method for preparing the DFO@GMs-pDA/PN composite scaffold for promoting vascularization and bone formation according to claim 1, 5, 6 or 7, wherein in the step (4), the mass-volume ratio of the DFO@GMs to the ethanol to the phosphate buffer salt solution is 200 mg:47-50 mL:45-51 mL, the reaction time is 10-14 h, and the stirring rate of the reaction is 200-250 r/min.
9. 9. The dfo@gms-pDA/PN composite stent prepared by the method for preparing the dfo@gms-pDA/PN composite stent for promoting vascularization and bone formation according to any one of claims 1-8.

Description

DFO@GMs-pDA/PN composite stent for promoting vascularization and bone formation as well as preparation method and application thereof Technical Field The invention relates to the technical fields of biomedical materials and biomedical engineering, in particular to a DFO@GMs-pDA/PN composite stent for promoting vascularization and bone formation, and a preparation method and application thereof. Background Bone tissue is a composite matrix composed of mineral phases that provide mechanical strength, osteoconductive matrix, and collagen phases that play a central role in progenitor cell differentiation, mineralization and maturation. Meanwhile, bone is a highly vascularized tissue that relies on the connection between blood vessels and bone cells to maintain its integrity. Bone regeneration is a complex, diverse and coordinated process, wherein the key to bone tissue regeneration is the coupling of the angiogenies to the bone formation. The vascular network is not only used as a way for recruiting bone progenitor cells and endothelial progenitor cells for bone tissues, but also is a channel for ensuring sufficient oxygen and nutrient substances of the bone tissues and timely discharging metabolic wastes, and simultaneously participates in the regulation and control of various cells and signal molecules in the bone regeneration process, so that the internal balance of the bone tissues can be maintained. Vascularized bone regeneration is a key to ensuring complete bone healing, accelerating the bone repair process, improving bone remodeling quality, while achieving osteogenic-angiogenic coupling in the bone healing process is a core problem that is required to face in current bone tissue engineering (Bone tissue engineering, BTE) techniques. In recent years, the scaffold designed in bone tissue regeneration research mainly adopts technologies such as electrostatic spinning, hydrogel, freeze drying and 3D printing, wherein the electrostatic spinning is a technology for preparing fine fibers from a polymer solution by utilizing electrostatic force, and has the advantages of extremely high surface area volume ratio, adjustable porosity, extensibility capable of adapting to various sizes and shapes, capability of controlling the composition of nanofibers and the like. When the electrospinning technology is used in BTE, the structure of the electrospinning device can simulate bone tissue extracellular matrix (Extracellularmatrix, ECM), the electrospinning device has high porosity and penetrability, and is convenient for diffusion of nutrient substances so as to be beneficial to growth, proliferation and migration of cells, and the electrospinning device has high entrapment efficiency on bioactive factors, polypeptides or medicines. PCL is approved by FDA for biomedicine, has proper tensile property, biocompatibility, osseointegration and biodegradability, has proper degradation speed, can not degrade too fast to support tissue regeneration, and can not degrade too slow to influence tissue regeneration, and is suitable as a BTE scaffold material. However, PCL itself presents a strong hydrophobicity that tends to prevent cell migration and delay integration of the scaffold material with the host tissue. Thus, pure PCL scaffolds suffer from poor cell adhesion and lack of bioactivity, which makes them problematic in that the scaffold-cell interface lacks biological function. NCs is a two-dimensional nano bone tissue engineering material, and has multiple functions, such as an inherent osteoinductive effect, and can improve mechanical properties, drug release capacity and the like. Loading NCs into polymer nanofibers can enhance and improve the mechanical properties and osteogenic activity of the scaffold. Secondly, the addition of NCs can improve the hydrophobicity of PCL, promote the adsorption of water, hydrolyze and degrade PCL chains, and is more beneficial to cell attachment, proliferation and migration. At the same time, NCs can increase the roughness of electrospun fibers and have been shown to be potentially osteoinductive in itself and promote biomineralization. Furthermore, NCs also have higher specific surface area and charge anisotropy, and exhibit strong drug binding and sustained release ability to various molecules. Microspheres are spherical microparticles that allow drug molecules to be dispersed therein, encapsulating and carrying the drug with its very tiny scaffold. Gelatin is a collagen degradation product in animal connective tissue or epidermal tissue, is a linear polymer formed by crosslinking 18 amino acids and polypeptides, has low antigenicity, good degradability and biocompatibility, and is also rich in arginine-glycine-aspartic acid sequences which have promotion effects on cell adhesion and migration. DFO promotes vascularization coupled osteogenesis primarily by (1) in the early stages of bone regeneration, DFO first promotes the expression of a series of angiogenic signals and active fact