Porosity of calcium metaphosphate glass ceramics
as a kind tissue engineering material★

Abstract

A new kind of porous foaming glass ceramics was prepared by sintering twice without any foaming agent to investigate the porosity of glass ceramics, analyze the porosity mechanism, make a hypothesis of foaming and validate the degradation and biological compatibility.Without adopting any foaming agent, the porous foaming glass ceramics were prepared.The Ca/P (mol) ratio of the prescription in raw materials was 0.47, and the sintering temperature was 680 ℃.There were mainly calcium metaphosphate (β-Ca (PO3)2, CMP) phases detected by X-ray diffraction. Liquid statics weighing method was adopted to calculate the water absorption (Wa), apparent porosity (Pa) and bulk density (Db) of CMP: 34.6 %, 43.6 % and 1.26 g/ cm3 respectively, which were similar to the former study. Detection by scanning electron microscopy (SEM) showed that the holes of CMP glass ceramics were conterminous one another, and there were big (100－300 μm) and small (2－20 μm) size holes. The CMP had been dipped in the normal saline at 37 ℃ for 28 days, and the weight-losing rate was 9.2%, and the surface topography of the CMP materials was changed in some places, for example there were some unknown item mesh in CMP surface, which shall be probe into further. The cell experiments showed that human bone marrow stem cells combined tightly with the surface of CMP materials and were growing into the inner of the big size holes, which demonstrated that porous CMP glass ceramics could be prepared by sintering twice without any foaming agent,utilizing the prescription character of powerful degradation of CMP glass phase.The biocompatibility experiments disclosed that porous calcium metaphosphate CMP had good biological compatibility.It is proved to be an excellent tissue engineering material through the degradation and biocompatibility experiments.

摘要
文章采用二次烧结法，没有添加发泡剂，制备了一种新型泡沫多孔玻璃陶瓷，主要考察了其多孔性能，分析了其成孔机制并作出成泡沫假设，验证其降解性能和生物相容性能。多孔玻璃陶瓷的制备过程中没有采用发泡剂，但材料可以发泡成孔，材料的配方中，其钙磷物质的量比为0.47，烧结温度选择680 ℃。X射线衍射图谱证实所得多孔玻璃陶瓷主晶相为偏磷酸钙（β-Ca(PO3)2,CMP）。液体(水)静力称重法计算出其吸水率、显气孔率及体积密度分别为34.6%，43.6%和1.26 g/cm3，与树脂成孔法结果类似。扫描电镜图显
示，偏磷酸钙玻璃陶瓷孔隙丰富，大孔(100～300 μm)和微孔(2～20 μm)相互贯通。降解性能检测显示，偏磷酸钙块浸泡于37 ℃ 生理盐水28 d，失重率9.2%；扫描电镜显示其表面形貌有较大的改变，出现了一些细小条状物质，原因需进一步的分析。细胞实验显示，人骨髓间充质干细胞在偏磷酸钙孔洞里大量生
长，且与偏磷酸钙材料表面结合紧密。提示采用二次烧结工艺，无需添加发泡剂，利用其自身配方和性质即可以制备多孔偏磷酸钙玻璃陶瓷，其发泡的主要原因为不定相偏磷酸钙的降解能力强。降解实验和生物相容实验表明所得偏磷酸钙玻璃陶瓷是一种非常有潜力的组织工程支架材料。
关键词： 玻璃陶瓷；多孔；偏磷酸钙；组织工程

吴岳恒，汤顺清，毛萱，成安衡，唐文洁，杜松林.组织工程支架材料偏磷酸钙玻璃陶瓷的多孔性能[J].中国组织工程研究与临床康复，2007，11(1):130-132 [www.zglckf.com/zglckf/ejournal/upfiles/07-1/1k-130(ps).pdf]