羟基磷灰石纳米纤维增强甲基丙烯酸酐改性明胶复合水凝胶的制备及性能

采用溶剂热法制备了具有超高长径比的羟基磷灰石(HAP)纳米纤维，并将其与甲基丙烯酸酐改性明胶(GelMA)结合，利用紫外光交联制备了HAP纳米纤维/GelMA复合水凝胶。通过SEM、XRD、力学测试、溶胀测试、降解测试、细胞培养等对HAP纳米纤维/GelMA复合水凝胶进行结构表征和性能测试。SEM断面观察表明，HAP纳米纤维/GelMA水凝胶呈三维孔隙贯通的多孔结构。力学实验表明，HAP纳米纤维能有效增强水凝胶的弹性模量，且随着HAP纳米纤维添加量的增加，力学性能增强效果越明显。溶胀实验表明，当HAP纳米纤维质量分数为5.2wt%~14.2wt%时，HAP纳米纤维复合水凝胶的溶胀率变化不明显，当质量分数为18.2wt%时，溶胀率降低。降解实验表明，HAP纳米纤维的加入能有效保持水凝胶结构形态，使其更加稳定可控。细胞包裹培养实验表明，HAP纳米纤维/GelMA复合水凝胶能为细胞提供良好的三维生长环境，表现出优良的生物相容性。本实验制备的HAP纳米纤维/GelMA复合水凝胶在组织工程领域有着良好的应用前景。 

Preparation and properties of hydroxyapatite nanofibers reinforced gelatin hydrogel modified by methacrylic anhydride composite hydrogel

Hydroxyapatite (HAP) nanofibers with ultra-high aspect ratio were prepared by a solvothermal method. HAP nanofibers reinforced composite hydrogel combined with gelatin modified by methacrylic anhydride(GelMA) was prepared by UV crosslinking. The composite hydrogel was characterized by SEM, XRD, mechanical test, swelling test, degradation test and cell culture, etc. The results of the cross-sectional morphology show that the HAP fiber/GelMA composite hydrogel has 3D porous structure with porous structure. Mechanical experiments show that HAP nanofibers can effectively enhance the elastic modulus of the composite hydrogel. With the increase of HAP nanofibers addition, the mechanical performance enhancement effect of the HAP/GelMA composite hydrogel is more obvious. The swelling experiments show that the swelling rate does not change significantly when the mass fraction of HAP fiber is 5.2wt%-14.2wt%, while the swelling rate decreases when the mass fraction is 18.2wt%. The degradation experiments show that the addition of HAP nanofibers can effectively maintain the structure of hydrogel and make it more stable and controllable. The cell co-culture experiments show that the HAP nanofibers/GelMA composite hydrogel can provide a great 3D growth environment for encapsulated cells, showing excellent biocompatibility. The HAP nanofibers/GelMA composite hydrogel prepared in the experiment has a good application prospect in the field of tissue engineering.