Sethuraman Swaminathan, Nair Lakshmi S, El-Amin Saadiq, Nguyen My-Tien N, Greish Yaser E, Bender Jared D, Brown Paul W, Allcock Harry R, Laurencin Cato T
Department of Chemical Engineering, University of Virginia, Charlottesville, Virginia, USA.
J Biomed Mater Res A. 2007 Sep 15;82(4):884-91. doi: 10.1002/jbm.a.31277.
Low temperature setting calcium phosphate cements (CPC) formed from reactive calcium phosphate precursors are receiving great attention in the fields of orthopaedics and tissue engineering. The purpose of this study was to evaluate the mechanical properties and osteocompatibility of a novel calcium deficient hydroxyapatite (CDSHA) with a Ca/P ratio of 1.6 developed in our laboratories and compare it to a previously developed calcium deficient hydroxyapatite (CDHA) with a Ca/P ratio of 1.5. The results demonstrated that the calcium-deficient hydroxyapatites (HA) formed from the CPCs were similar to biological HA at physiological temperature and the elastic moduli of CDHA and CDSHA were found to be 174.42 +/- 20.41 MPa (p < 0.05) and 115.86 +/- 24.8 MPa (p < 0.05), respectively. The surface morphologies of the two calcium deficient HA's formed were identical with a micro/nano porous structure as evidenced from SEM. The cellular proliferation on CDHA, and CDSHA, was comparable to the control, tissue culture polystyrene (TCPS) (p < 0.05). Alkaline phosphatase activity was significantly elevated on CDHA and CDSHA matrices at early time points when compared with the control (TCPS) (p < 0.05). Osteoblast cells gene expression on CDHA, and CDSHA showed type I collagen, alkaline phosphatase, osteocalcin, and osteopontin activity at both 7 and 14 days of culture. Thus, novel calcium-deficient HAs, CDHA, and CDSHA formed at low temperature are promising candidates for orthopaedic applications based on their ability to promote osteoblast cell adhesion and gene expression in vitro.
由活性磷酸钙前体形成的低温凝固磷酸钙骨水泥（CPC）在骨科和组织工程领域受到了广泛关注。本研究的目的是评估我们实验室研发的一种新型钙磷比为1.6的缺钙羟基磷灰石（CDSHA）的力学性能和骨相容性，并将其与之前研发的钙磷比为1.5的缺钙羟基磷灰石（CDHA）进行比较。结果表明，由CPC形成的缺钙羟基磷灰石（HA）在生理温度下与生物HA相似，发现CDHA和CDSHA的弹性模量分别为174.42±20.41MPa（p<0.05）和115.86±24.8MPa（p<0.05）。扫描电子显微镜（SEM）显示，形成的两种缺钙HA的表面形态相同，均为微/纳米多孔结构。CDHA和CDSHA上的细胞增殖与对照组织培养聚苯乙烯（TCPS）相当（p<0.05）。与对照（TCPS）相比，在早期时间点，CDHA和CDSHA基质上的碱性磷酸酶活性显著升高（p<0.05）。在培养7天和14天时，CDHA和CDSHA上的成骨细胞基因表达均显示出I型胶原蛋白、碱性磷酸酶、骨钙素和骨桥蛋白的活性。因此，基于其在体外促进成骨细胞粘附和基因表达的能力，低温形成的新型缺钙HA、CDHA和CDSHA有望成为骨科应用的候选材料。
