丝素蛋白/纳米羟基磷灰石复合材料的制备及3D打印成型研究

Study on Preparation and Three-Dimension Print of Silk Fibroin/Nano-Hydroxyapatite Composites

摘要: 针对单一羟基磷灰石制成的骨件易碎、强度差等问题，采用共沉淀法用桑蚕丝和无机盐制备了丝素蛋白(SF)与纳米羟基磷灰石(HA)的复合材料。采用扫描电镜(SEM)、傅立叶红外光谱、X射线衍射(XRD)对复合材料的结构进行表征。采用3D打印的方式将复合材料打印成型，并进行了抗压强度测试。结果表明：此方法得到的HA/SF复合材料粒径约为20~50 nm，长度约为80~120 nm，具有一定的长轴取向性，丝素蛋白与羟基磷灰石复合弱化了羟基磷灰石的结晶状态。骨修复材料的成型可以通过3D打印来实现，成型后其抗压强度可达到52 MPa，可以满足人体骨的强度要求。

Abstract: A composite material of silk fibroin (SF) and nano-hydroxyapatite (HA) was prepared by co-precipitation method using mulberry silk and inorganic salt to solve the problem of brittle fracture and low toughness of single hydroxyapatite. The composite material was characterized by scanning electron microscopy (SEM), Fourier transform infrared spectrometer (FT-IR) and X-ray diffraction (XRD). The tensile tests of the composites which were printed via three-dimension printer were done. The results show that the size of the HA/SF is about 20 - 50 nm. The length of the nano-particles with long axis orientation is about 80 - 120 nm. The crystalline state of HA was weakened by the SF in HA/SF. HA/SF scaffolds were printed by three-dimension printer. Via adding nanocellulose disperses solution into the HA/SF composite, the compressive strength of HA/SF scaffolds can be 52 MPa which can be satisfied with the demand of body bone. The composite scaf-folds have uniform pores compared to those scaffolds obtained by foaming, freeze-drying, etc. The size of pores is about 250 - 350 μm. The suitable concentration of nanocellulose disperses solution to help to form and increase toughness is 3%. The ratio of HA/SF and nanocellulose is 1:2. So HA/SF composite can be a suitable bone repair material. Three-dimensional printing is an ideal process to manufacture bone scaffolds efficiently.