Kim Hae-Won, Koh Young-Hag, Kong Young-Min, Kang Jun-Gu, Kim Hyoun-Ee
School of Materials Science and Engineering, Seoul National University, Seoul, 151-742, Korea.
J Mater Sci Mater Med. 2004 Oct;15(10):1129-34. doi: 10.1023/B:JMSM.0000046395.76435.60.
Strontium (Sr) substituted calcium phosphate ceramics were fabricated using a powder precipitation method. The Sr ions were added up to 8 mol % to replace the Ca ions during the powder preparation. Composition analysis showed that the added Sr was not fully incorporated within the as-precipitated apatite structure, presumably being washed out during the powder preparation. After calcination, the Sr containing powders were crystallized into apatite and tricalcium phosphate (TCP), that is, biphasic calcium phosphates were formed. The amount of TCP increased with increasing the Sr addition. The lattice parameters of the calcined powders increased gradually with Sr substitution in both the a- and c-axis. However, the obtained values deviated slightly from the calculated ones at higher Sr additions (>4%) due to the partial substitution of Sr ions. The microstructure of the sintered bodies changed with the Sr addition due to the formation of TCP. The Vickers hardness increased slightly from 5.2 to 5.5 MPa with increasing Sr addition, which was driven by the HA+TCP biphasic formation. The osteoblast-like cells cultured on the Sr-substituted biphasic sample spread and grew actively. The proliferation rate of the cells was higher in the samples containing more Sr. The alkaline phosphate activity of the cells was expressed to a higher degree with increasing Sr addition. These observations confirmed the enhanced cell viability and differentiation of the Sr-substituted biphasic calcium phosphate ceramics.
采用粉末沉淀法制备了锶（Sr）取代的磷酸钙陶瓷。在粉末制备过程中，添加高达8摩尔%的Sr离子以取代Ca离子。成分分析表明，添加的Sr并未完全掺入沉淀的磷灰石结构中，可能在粉末制备过程中被洗出。煅烧后，含Sr的粉末结晶为磷灰石和磷酸三钙（TCP），即形成了双相磷酸钙。TCP的量随着Sr添加量的增加而增加。煅烧粉末的晶格参数在a轴和c轴上均随着Sr取代而逐渐增加。然而，由于Sr离子的部分取代，在较高Sr添加量（>4%）时，获得的值与计算值略有偏差。由于TCP的形成，烧结体的微观结构随Sr添加量而变化。随着Sr添加量的增加，维氏硬度从5.2 MPa略微增加到5.5 MPa，这是由HA+TCP双相形成所驱动的。在Sr取代的双相样品上培养的成骨样细胞能够积极地铺展和生长。在含Sr量更高的样品中，细胞的增殖率更高。随着Sr添加量的增加，细胞的碱性磷酸酶活性表达程度更高。这些观察结果证实了Sr取代的双相磷酸钙陶瓷的细胞活力和分化增强。
