Oral repair membrane with antibacterial and bone integration properties and preparation thereof

Abstract

Oral repair membrane with antibacterial and bone integration properties and its preparation. Polycaprolactone is added to hexafluoroisopropanol to form a carrier inner layer basic electrospinning liquid; hydroxyapatite and bone morphogenetic protein are separately added to the inner layer basic electrospinning liquid to form an inner layer coaxial electrospinning shell liquid and an inner layer coaxial electrospinning core liquid; the hexafluoroisopropanol solution of polycaprolactone and the anhydrous ethanol solution of polyvinylpyrrolidone are evenly mixed to form a combined middle layer uniaxial electrospinning liquid; polyvinylpyrrolidone is added to the anhydrous ethanol solution to form an antibacterial outer layer basic electrospinning liquid; zinc oxide and an antibacterial agent are separately added to the outer layer basic electrospinning liquid to form an outer layer coaxial electrospinning shell liquid and an outer layer coaxial electrospinning core liquid; the formed inner layer coaxial electrospinning core liquid and inner layer coaxial electrospinning shell liquid are used for coaxial electrospinning to form a carrier inner layer; after electrospinning layer by layer, an integrated composite oral repair membrane with a carrier inner layer, a combined middle layer and an antibacterial outer layer is formed.

Description

Technical Field

[0001] The invention relates to an oral repair membrane. Background Art

[0002] Guided bone regeneration (GBR) is the use of a barrier membrane to promote new bone formation in bone defects. The barrier membrane prevents epithelial cell infiltration and the downward growth of connective tissue in the defect area. It provides space for the migration of osteoblasts and osteoblasts and the growth of new bone.

[0003] Polycaprolactone (PCL) is a biodegradable aliphatic polyester. It is used in biomedical applications due to its biocompatibility, good mechanical properties and biodegradability. It does not require secondary surgical resection and has become an important raw material for biomedicine. A mature GBR membrane requires a complex integration of various properties: sufficient rigidity to maintain space for tissue regeneration and good softness to adapt to the tissue; effective resistance to the occupation of soft tissue cells and good ability to guide the growth of osteoblast-related cells; resistance to bacteria in the microbially rich oral environment and promotion of osteogenesis in bone defects. However, the use of polycaprolactone (PCL) alone to prepare oral repair membranes has problems such as poor antibacterial and bone integration capabilities. In addition, in order to change the performance of the GBR membrane, other effective bactericidal ingredients can also be added.

[0004] Oral repair membranes generally include collagen membranes, biological and / or biomimetic membranes, such as those disclosed in CN112999403A, CN112999430B, CN112717205B, CN118403223A, CN115025296B, CN117959502A, CN115006597B, CN105688288B, CN105457107B, etc.

[0005] Oral repair membranes are also commonly prepared using electrospinning technology, such as the multilayer composite membrane containing piezoelectric materials disclosed in CN116407688A, the three-layer structure oral repair membrane of gelatin layer-polycaprolactone layer-gelatin layer with gradient fiber diameter disclosed in CN109513046B, the composite hydrogel fiber membrane disclosed in CN118286507A, and the three-layer oral repair membrane with different pore sizes disclosed in CN116269868A.

[0006] However, these oral restoration membranes also need to be improved in terms of antibacterial and bone integration capabilities. Summary of the invention

[0007] The purpose of the present invention is to provide an oral repair membrane, which can at least improve the antibacterial and bone integration capabilities of the oral repair membrane, thereby increasing the success rate of oral implantation.

[0008] According to one aspect of the present invention, a method for preparing an oral repair membrane is provided, comprising:

[0009] Adding polycaprolactone to hexafluoroisopropanol and mixing evenly to form a carrier inner layer basic electrospinning solution, wherein the mass content of polycaprolactone is 3% to 7%;

[0010] Hydroxyapatite is added to the carrier inner layer base electrospinning solution to form an inner layer coaxial electrospinning shell solution, wherein the mass content of hydroxyapatite is 0.1% to 0.3%;

[0011] Bone morphogenetic protein is added to the carrier inner layer base electrospinning solution to form an inner layer coaxial electrospinning core solution, wherein the mass content of the bone morphogenetic protein is 0.2% to 0.6%;

[0012] The hexafluoroisopropanol solution of polycaprolactone and the anhydrous ethanol solution of polyvinyl pyrrolidone are mixed evenly to form a combined intermediate layer uniaxial electrospinning solution, wherein the mass content of polycaprolactone is 1% to 5%, the mass content of polyvinyl pyrrolidone is 1% to 5%, and the volume ratio of hexafluoroisopropanol to anhydrous ethanol is (1:2) to (2:1);

[0013] Add polyvinyl pyrrolidone to the anhydrous ethanol solution, mix well to form an antibacterial outer layer basic electrospinning solution, wherein the mass content of polyvinyl pyrrolidone is 5% to 15%;

[0014] Adding zinc oxide to the antibacterial outer layer base electrospinning solution to form an outer layer coaxial electrospinning shell solution, wherein the mass content of zinc oxide is 0.2% to 0.6%;

[0015] An antibacterial agent is added to the antibacterial outer layer base electrospinning liquid to form an outer layer coaxial electrospinning core liquid, wherein the mass content of the antibacterial agent is 0.1% to 0.3%;

[0016] Using the formed inner layer coaxial electrospinning core liquid and inner layer coaxial electrospinning shell liquid to perform coaxial electrospinning to form a carrier inner layer;

[0017] Then, the formed bonding middle layer uniaxial electrospinning liquid is used to perform uniaxial electrospinning to form a bonding middle layer on the carrier inner layer;

[0018] Finally, the formed outer coaxial electrospinning core liquid and outer coaxial electrospinning shell liquid are used for coaxial electrospinning to form an antibacterial outer layer, thereby finally forming an integrated composite oral repair membrane.

[0019] According to the preparation method of the present invention, the bone morphogenetic protein may be, for example, rhBMP-2.

[0020] According to the preparation method of the present invention, the antibacterial agent can be, for example, a small molecule antibacterial drug such as metronidazole.

[0021] According to the preparation method of the present invention, the average molecular weight of polycaprolactone can be 8000-10000, and the average molecular weight of polyvinyl pyrrolidone can be 1300000.

[0022] According to the preparation method of the present invention, during coaxial or uniaxial electrospinning, the distance between the spinning nozzle and the receiving mandrel is between 12 and 18 cm; the starting parameters of the electrospinning are: the receiving mandrel speed is 30 to 50 rpm, the positive voltage is 5 to 10 kV, the solution flow rate is 0.5 to 2.0 mL / h; and the electrospinning time is 1.5 to 3 hours.

[0023] The preparation method of the invention is simple, low in cost and easy to be applied on an industrial scale.

[0024] According to another aspect of the present invention, there is also provided an oral repair membrane, which is prepared according to the above method.

[0025] According to the oral repair membrane of the present invention, the pore size of the carrier inner layer is preferably 30-60 μm, and the pore size of the antibacterial outer layer is preferably 1-10 μm.

[0026] The oral repair membrane prepared according to the present invention has a three-layer structure. The outer layer containing PVP can effectively prevent fibroblasts from passing through the repair membrane and has a slow-release antibacterial effect; the inner layer containing PCL provides a carrier for bone cell growth and has a bone integration effect; the middle layer containing PVP and PCL tightly combines the inner layer and the outer layer, and makes the prepared oral repair membrane have the required mechanical strength. The oral repair membrane of the present invention can effectively improve the antibacterial and bone integration capabilities of the oral repair membrane through the synergistic effect of multiple factors, thereby improving the success rate of oral implantation. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] Figure 1 The figure is a scanning electron microscope morphology image of the inner layer of the three-layer oral repair membrane prepared according to the present invention.

[0028] Figure 2 The figure is a scanning electron microscope morphology image of the outer layer of the three-layer oral repair membrane prepared according to the present invention.

[0029] Figure 3 The figure is a scanning electron microscope morphology image of the middle layer of the three-layer oral repair film prepared according to the present invention. DETAILED DESCRIPTION

[0030] The present invention will be described in detail below with reference to the accompanying drawings.

[0031] 1. Preparation of electrospinning solution for each membrane layer

[0032] 1) Carrier inner layer base electrospinning solution: Weigh 0.8 g polycaprolactone particles, add to 10 mL hexafluoroisopropanol, place on a magnetic stirrer, stir for 12 hours, and stir the mixed solution thoroughly;

[0033] Then the prepared carrier inner layer base electrospinning solution was divided into two equal parts: one part was added with 0.01 g of hydroxyapatite to form the inner layer coaxial electrospinning shell solution, and the other part was added with 0.02 g of bone morphogenetic protein (rhBMP-2 type) to form the inner layer coaxial electrospinning core solution. The inner layer coaxial electrospinning shell solution and core solution were stirred on a magnetic stirrer for 0.5 hours.

[0034] 2) Antibacterial outer layer base electrospinning solution: weigh 0.8 g of polyvinyl pyrrolidone powder, add it to 10 mL of anhydrous ethanol, place it on a magnetic stirrer, stir for 12 hours, and stir the mixed solution thoroughly;

[0035] Then the prepared antibacterial outer layer base electrospinning liquid was divided into two equal parts: one part was added with 0.02 g of zinc oxide to form the outer layer coaxial electrospinning shell liquid, and the other part was added with 0.01 g of small molecule antibacterial drug metronidazole to form the outer layer coaxial electrospinning core liquid. The outer layer coaxial electrospinning shell liquid and core liquid were stirred on a magnetic stirrer for 0.5 hours.

[0036] 3) Combine the intermediate layer uniaxial electrospinning solution: weigh 0.8 g of polyvinyl pyrrolidone powder and add it to 10 mL of anhydrous ethanol; weigh 0.8 g of polycaprolactone particles and add it to 10 mL of hexafluoroisopropanol. Place the two solutions separately on a magnetic stirrer and stir for 12 hours; then pour the two solutions together and mix them thoroughly for 0.5 hours.

[0037] 2. Electrospinning to prepare oral repair membrane

[0038] The obtained spinning solution was injected into the syringe pump of the electrospinning equipment for electrospinning. The distance between the spinning nozzle and the receiving mandrel was 15 cm, and the electrospinning time was 2 hours; the receiving mandrel speed of the inner layer was 40 rpm, the positive voltage was 7 kV, and the solution flow rate was 1 mL / h; the receiving mandrel speed of the outer layer was 40 rpm, the positive voltage was 5.5 kV, and the solution flow rate was 1 mL / h; the receiving mandrel speed of the middle layer was 40 rpm, the positive voltage was 8 kV, and the solution flow rate was 1 mL / h. Both the inner and outer layers were coaxially electrospun, that is, the corresponding core liquid and shell liquid were used for coaxial electrospinning. Uniaxial electrospinning was used for the combined middle layer. Finally, a three-layer laminated structure composite membrane in the form of polycaprolactone fiber membrane-polycaprolactone / polyvinyl pyrrolidone fiber membrane-polyvinyl pyrrolidone fiber membrane was prepared.

[0039] Performance Testing

[0040] Table 1 lists the corresponding parameters measured for each layer of the above three-layer composite film

[0041] .

[0042] Figure 1-3 The scanning electron microscope morphology images of the inner layer (magnified 10,000 times), outer layer (magnified 10,000 times) and middle layer (magnified 5,000 times) of the oral repair membrane (composite membrane) prepared above are shown. It can be seen from the figure that the gap of the inner electrospun layer of the present invention is relatively large, and the gap size of the example is mainly concentrated between 41 and 46 μm, and the gap of the outer electrospun layer is relatively small, and the gap size of the example is mainly concentrated between 3 and 5 μm. The larger gaps in the inner layer can facilitate the application of bone cells, which is beneficial to bone integration and bone absorption, improve the growth of regenerated bone and the combination of implants and alveolar bones, while the smaller gaps in the outer layer can effectively block cells such as epithelial cells, fibers and gingival tissues from passing through the repair membrane of the present invention, block the growth of these tissues on the surface of the alveolar bone to be repaired, and improve the repair effect. The presence of an appropriate gap size is conducive to the infiltration of oral fluids, providing a necessary environment for the growth of bone cells and improving the effect of bone integration. The middle layer can mainly provide a better bonding strength for the combination of the outer layer and the inner layer.

Claims

1. A method for preparing an oral repair membrane, comprising: Adding polycaprolactone to hexafluoroisopropanol and mixing evenly to form a carrier inner layer basic electrospinning solution, wherein the mass content of polycaprolactone is 3% to 7%; Hydroxyapatite is added to the carrier inner layer base electrospinning solution to form an inner layer coaxial electrospinning shell solution, wherein the mass content of hydroxyapatite is 0.1% to 0.3%; Bone morphogenetic protein is added to the carrier inner layer base electrospinning solution to form an inner layer coaxial electrospinning core solution, wherein the mass content of the bone morphogenetic protein is 0.2% to 0.6%; The hexafluoroisopropanol solution of polycaprolactone and the anhydrous ethanol solution of polyvinyl pyrrolidone are mixed evenly to form a combined intermediate layer uniaxial electrospinning solution, wherein the mass content of polycaprolactone is 1% to 5%, the mass content of polyvinyl pyrrolidone is 1% to 5%, and the volume ratio of hexafluoroisopropanol to anhydrous ethanol is (1:2) to (2:1); Add polyvinyl pyrrolidone to the anhydrous ethanol solution, mix well to form an antibacterial outer layer basic electrospinning solution, wherein the mass content of polyvinyl pyrrolidone is 5% to 15%; Adding zinc oxide to the antibacterial outer layer base electrospinning solution to form an outer layer coaxial electrospinning shell solution, wherein the mass content of zinc oxide is 0.2% to 0.6%; An antibacterial agent is added to the antibacterial outer layer base electrospinning liquid to form an outer layer coaxial electrospinning core liquid, wherein the mass content of the antibacterial agent is 0.1% to 0.3%; Using the formed inner layer coaxial electrospinning core liquid and inner layer coaxial electrospinning shell liquid to perform coaxial electrospinning to form a carrier inner layer; Then, the formed bonding middle layer uniaxial electrospinning liquid is used to perform uniaxial electrospinning to form a bonding middle layer on the carrier inner layer; Finally, the formed outer coaxial electrospinning core liquid and outer coaxial electrospinning shell liquid are used for coaxial electrospinning to form an antibacterial outer layer, thereby finally forming an integrated composite oral repair membrane.

2. An oral repair membrane prepared according to the method of claim 1.

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