Department of Materials Science and Engineering, National Taiwan University, Taipei, Taiwan.
Department of Orthopedic Surgery, Bone and Joint Research Center, Chang Gung Memorial Hospital at Linkou, College of Medicine, Chang Gung University, Taoyuan, Taiwan.
J Mater Sci Mater Med. 2021 Dec 4;32(12):146. doi: 10.1007/s10856-021-06622-7.
The formation of a nano-apatite surface layer is frequently considered a measure of bioactivity, especially for non-phosphate bioceramics. In the present study, strontium-doped calcium sulfate, (Ca,Sr)SO, was used to verify the feasibility of this measure. The (Ca,Sr)SO specimen was prepared by mixing 10% SrSO by weight with 90% CaSO·½HO powder by weight. A solid solution of (Ca,7.6%Sr)SO was then produced by heating the powder mixture at 1100 °C for 1 h. The resulting (Ca,Sr)SO specimen was readily degradable in phosphate solution. A newly formed surface layer in the form of flakes was formed within one day of specimen immersion in phosphate solution. Structural and microstructure-compositional analyses indicated that the flakes were composed of octacalcium phosphate (OCP) crystals. An amorphous interface containing OCP nanocrystals was found between the newly formed surface layer and the remaining (Ca,Sr)SO specimen. The specimen was also implanted into a rat distal femur bone defect. In addition to new bone, fibrous tissue and inflammatory cells were found to interlace the (Ca,Sr)SO specimen. The present study indicated that a more comprehensive evaluation is needed to assess the bioactivity of non-phosphate bioceramics. The newly formed surface layer on the (Ca,Sr)SO specimen after soaking in phosphate solution for 28 days.
纳米磷灰石表面层的形成通常被认为是生物活性的衡量标准，特别是对于非磷酸盐生物陶瓷。在本研究中，使用掺锶硫酸钙（Ca，Sr）SO 来验证这一措施的可行性。（Ca，Sr）SO 标本通过将重量比为 10%的 SrSO 与重量比为 90%的 CaSO·½HO 粉末混合来制备。然后，通过将粉末混合物在 1100°C 下加热 1 小时，生成（Ca，7.6%Sr）SO 的固溶体。所得（Ca，Sr）SO 标本在磷酸盐溶液中易降解。在将标本浸入磷酸盐溶液一天后，形成了一层新的片状表面层。结构和微观结构-组成分析表明，薄片由八钙磷酸盐（OCP）晶体组成。在新形成的表面层和剩余的（Ca，Sr）SO 标本之间发现了含有 OCP 纳米晶体的非晶界面。该标本也被植入大鼠股骨远端骨缺损。除了新骨外，还发现纤维组织和炎症细胞交织在（Ca，Sr）SO 标本中。本研究表明，需要更全面的评估来评估非磷酸盐生物陶瓷的生物活性。在磷酸盐溶液中浸泡 28 天后，（Ca，Sr）SO 标本上形成的新表面层。
