缺钙纳米羟基磷灰石材料的细胞相容性

Cellular biocompatibility of calcium deficient nanophase hydroxyapatite

目的纳米羟基磷灰石具有广阔的应用前景,然而不同种类纳米羟基磷灰石的生物学性能差异尚不明确。本研究尝试评价缺钙纳米晶羟基磷灰石材料的细胞相容性,并与标准钙磷比羟基磷灰石材料进行比较。方法采用原代培养的成骨细胞检测两种不同钙磷比羟基磷灰石的细胞相容性,两种材料均为化学湿法合成的纳米级羟基磷灰石。羟基磷灰石的纳米颗粒为棒状晶粒,晶粒之间呈无序的交叉排列,标准钙磷比材料晶粒直径40～55nm,长度79～100nm;缺钙羟基磷灰石的纳米晶直径为25～40nm,长度75～100nm。采用MTT法观察成骨细胞在两种材料表面3d后的增殖情况,并用SEM观察第3d时细胞在材料表面的附着形态,细胞培养第5d时对碱性磷酸酶活性进行检测。结果成骨细胞在缺钙纳米晶羟基磷灰石表面的细胞增殖数量显著高于标准钙磷比纳米晶羟基磷灰石,细胞数量相当于后者的130%。在两种羟基磷灰石材料表面成骨细胞胞核明显,胞浆丰富,具有正常的细胞形态;在缺钙纳米晶羟基磷灰石表面细胞出现大量细胞伪足和细小突触结构,表现出更为活跃的细胞伸展形态。具有更高的碱性磷酸酶活性,缺钙纳米晶羟基磷灰石表面的细胞碱性磷酸酶相对活性值为0.73,标准钙磷比材料为0.13。结论缺钙纳米羟基磷灰石表面较标准钙磷比羟基磷灰石更适于成骨细胞生长,对成骨细胞碱性磷酸酶表达也有一定促进作用。

Objective Nano-hydroxyapatite has a broad application prospects. However, the difference of biological properties is still unclear. This study is aimed to evaluate and compare the cellular biocompatibility of calcium deficient nanophase hydroxyapatite with standard hydroxyapatite. Methods Primarily cultured osteoblasts were used to examine the cellular biocompatibility of different hydroxyapatite, which were both synthesized by chemical wet method. The crystals of nanophase hydroxyapatite were of disorderly arranged rod shape crystals. The crystal of standard hydroxyapatite was 40-55nm in diameter and 79-100nm in length. Calcium deficient hydroxyapatite was 25-40nm in diameter and 75-100nm in length. MTT method was used to evaluate the proliferation of osteoblast on the third day, ALP test was carried out on the fifth day, and SEM was used to examine the morphology of osteoblasts on the third day. Results The result indicated that CDHA surface had more osteoblasts, the quantity was 130% of the standard one. Osteoblast spread well with obvious nucleus and rich plasma. On the surface of CDHA, osteoblast had more protrusions and mini filopodia exhibiting a more active cell morphology. The ALP level of CDHA was also higher than the latter （0.73 VS 0.13）. Conclusions Surface of nanophase CDHA was more suitable for osteoblasts growth than nanophase HA, at the same time it was helpful for ALP synthesis.