A method for preparing biological scaffolds by 3D printing

Abstract

The invention provides a method for preparing a biological scaffold by 3D printing. The method comprises the steps of grinding allogeneic bones or heterogeneous bones at a low temperature in a freezing grinder to obtain a printing material, modeling 3D printing with the aid of a computer, and then performing post treatment in a genipin solution. The prepared biological scaffold has good biological compatibility, and the bone graft material does not have toxicity, rejection, mutagenicity or antigenicity in vivo, and does not disturb bone and tissue regeneration; the prepared biological scaffold can be gradually degraded and absorbed and replaced by autologous bone tissues, can bear the pressure close to 20MPa with normal bone cortex, and has good initial mechanical properties; and the elastic modulus is gradually reduced, stress shielding is avoided, fracture, collapse and loosening of implants in the long-term healing process are avoided, bone fusion can be accelerated, and the implants can be finally completely converted into autologous bone tissues.

Description

technical field

[0001] The invention relates to a biological scaffold, in particular to a method for preparing an absorbable biological scaffold by 3D printing. Background technique

[0002] For diseased or damaged bone tissue, it is necessary to use substitute bone materials for bone repair to promote bone fusion. The use of autologous bone graft is recognized as the "gold standard" with the highest fusion rate. However, autologous bone materials are difficult to obtain, and the amount of materials obtained is limited, which increases additional trauma and lacks support strength. Therefore, exploring the ideal bone graft substitute material is an important research topic in this field.

[0003] Currently commonly used bone graft materials include allograft bone, metal materials and polyetheretherketone (PEEK) resin materials. Although the allograft bone has good degradability, absorption and substitution, it is difficult to control the rate, resulting in unreliable mecha...

Examples

Embodiment 1

[0033] Example of Bone Graft Scaffold Prepared by Calf Bone 3D Printing

[0034] Take the following steps:

[0035] (1). Put the calf bone tissue into the grinding container of the frozen grinder, immerse it in liquid nitrogen (-30~-50°C), grind it for 2 hours, dry it at room temperature for 60 minutes, and then screen it with an 80-mesh sieve Bone powder with a diameter of <180 μm is ready for use;

[0036] (2). Using the bone powder obtained in step (1) as a raw material, using collagen gel aqueous solution (5wt%) as a binder, under room temperature conditions, the bone powder with a weight percentage of 50wt% and the glue with a weight percentage of 50wt% The binder is placed in the ball mill tank, and is made into a slurry raw material through ball milling for 30 minutes;

[0037] (3). Put the slurry raw material obtained in step (2) into a glass test tube, and centrifuge for 5 minutes at a temperature of 8°C and a humidity of 90% at a speed of 3000 rpm to obtain a print...

Embodiment 2

[0044] Performance tests were performed on the bioscaffold prepared in Example 1, including biocompatibility, absorption and degradation performance, and mechanical properties.

[0045] Biodescriptiveness: A 10×10×1 mm bioscaffold sheet was prepared according to the method in Example 1, placed at the bottom of a 96-well culture dish, and infiltrated with α-MEM for 24 hours. Rabbit bone marrow mesenchymal stem cells (under the conditions of temperature 37°C, CO2 concentration 5%, humidity 95%) were subcultured to the third generation, and the cell density was adjusted to 3×10 5 Cells / ml, inoculate the cells in the culture wells with the support sheet at the bottom, set up the control culture wells without the membrane sheet, 5 parallel culture wells, the medium is α-MEM medium plus 10% newborn bovine serum, 800 μl per well , at 37°C, 5% CO 2 , cultured under 95% humidity conditions, and the medium was changed regularly. After 24 hours, CKK8 solution was added and incubated at...

Embodiment 3

[0050] Example of Allogeneic Bone 3D Printed Bone Graft Scaffold

[0051] Take the following steps:

[0052] (1). Put the allograft bone tissue into the grinding container of the cryogenic grinder, immerse in liquid nitrogen (-50~-65°C), pulverize and grind for 4 hours with a hammer, dry at room temperature for 30 minutes, and then screen with a sieve Bone powder with a diameter of less than 150 μm is prepared for use;

[0053] (2). Using the bone powder obtained in step (1) as a raw material, using polycaprolactone aqueous solution (10wt%) as a binder, under room temperature conditions, the bone powder with a weight percentage of 70wt% and the adhesive with a weight percentage of 30wt% The binder is placed in the ball mill tank, and is made into a slurry raw material through ball milling for 30 minutes;

[0054] (3). Put the slurry raw material obtained in step (2) into a glass test tube, and centrifuge for 5 minutes at a temperature of 4°C and a humidity of 85% at a speed ...

technical field

[0001] The invention relates to a biological scaffold, in particular to a method for preparing an absorbable biological scaffold by 3D printing. Background technique

[0002] For diseased or damaged bone tissue, it is necessary to use substitute bone materials for bone repair to promote bone fusion. The use of autologous bone graft is recognized as the "gold standard" with the highest fusion rate. However, autologous bone materials are difficult to obtain, and the amount of materials obtained is limited, which increases additional trauma and lacks support strength. Therefore, exploring the ideal bone graft substitute material is an important research topic in this field.

[0003] Currently commonly used bone graft materials include allograft bone, metal materials and polyetheretherketone (PEEK) resin materials. Although the allograft bone has good degradability, absorption and substitution, it is difficult to control the rate, resulting in unreliable mecha...

Examples

Embodiment 1

[0033] Example of Bone Graft Scaffold Prepared by Calf Bone 3D Printing

[0034] Take the following steps:

[0035] (1). Put the calf bone tissue into the grinding container of the frozen grinder, immerse it in liquid nitrogen (-30~-50°C), grind it for 2 hours, dry it at room temperature for 60 minutes, and then screen it with an 80-mesh sieve Bone powder with a diameter of <180 μm is ready for use;

[0036] (2). Using the bone powder obtained in step (1) as a raw material, using collagen gel aqueous solution (5wt%) as a binder, under room temperature conditions, the bone powder with a weight percentage of 50wt% and the glue with a weight percentage of 50wt% The binder is placed in the ball mill tank, and is made into a slurry raw material through ball milling for 30 minutes;

[0037] (3). Put the slurry raw material obtained in step (2) into a glass test tube, and centrifuge for 5 minutes at a temperature of 8°C and a humidity of 90% at a speed of 3000 rpm to obtain a print...

Embodiment 2

[0044] Performance tests were performed on the bioscaffold prepared in Example 1, including biocompatibility, absorption and degradation performance, and mechanical properties.

[0045] Biodescriptiveness: A 10×10×1 mm bioscaffold sheet was prepared according to the method in Example 1, placed at the bottom of a 96-well culture dish, and infiltrated with α-MEM for 24 hours. Rabbit bone marrow mesenchymal stem cells (under the conditions of temperature 37°C, CO2 concentration 5%, humidity 95%) were subcultured to the third generation, and the cell density was adjusted to 3×10 5 Cells / ml, inoculate the cells in the culture wells with the support sheet at the bottom, set up the control culture wells without the membrane sheet, 5 parallel culture wells, the medium is α-MEM medium plus 10% newborn bovine serum, 800 μl per well , at 37°C, 5% CO 2 , cultured under 95% humidity conditions, and the medium was changed regularly. After 24 hours, CKK8 solution was added and incubated at...

Embodiment 3

[0050] Example of Allogeneic Bone 3D Printed Bone Graft Scaffold

[0051] Take the following steps:

[0052] (1). Put the allograft bone tissue into the grinding container of the cryogenic grinder, immerse in liquid nitrogen (-50~-65°C), pulverize and grind for 4 hours with a hammer, dry at room temperature for 30 minutes, and then screen with a sieve Bone powder with a diameter of less than 150 μm is prepared for use;

[0053] (2). Using the bone powder obtained in step (1) as a raw material, using polycaprolactone aqueous solution (10wt%) as a binder, under room temperature conditions, the bone powder with a weight percentage of 70wt% and the adhesive with a weight percentage of 30wt% The binder is placed in the ball mill tank, and is made into a slurry raw material through ball milling for 30 minutes;

[0054] (3). Put the slurry raw material obtained in step (2) into a glass test tube, and centrifuge for 5 minutes at a temperature of 4°C and a humidity of 85% at a speed ...