Dr. M. N. Dastur School of Materials Science and Engineering, Indian Institute of Engineering Science and Technology, Shibpur, Howrah 711103, India.
Dr. M. N. Dastur School of Materials Science and Engineering, Indian Institute of Engineering Science and Technology, Shibpur, Howrah 711103, India; Bioceramics and Coating Division, CSIR-Central Glass & Ceramic Research Institute, 196 Raja S.C. Mullick Road, Kolkata 700032, India.
J Mech Behav Biomed Mater. 2019 Feb;90:328-336. doi: 10.1016/j.jmbbm.2018.10.027. Epub 2018 Oct 17.
Synthesis of strontium-doped hydroxyapatite from Mercenaria clam shells has been carried out by hydrothermal method. The doping of bioceramic, processed from biogenic resources is mostly unexplored. The objective is to understand the effect of strontium (Sr) incorporation on phase stability, sintering behaviour, mechanical properties and cytotoxicity of hydroxyapatite (HAp) derived from clam shells. The different molar concentrations of Sr, varies from 10, 30, 50, 70% of Ca, were substituted into the HAp. The synthesized powders were sintered at 1200 °C in air. The as synthesized powders and sintered specimens were characterized using X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR) and high resolution transmission electron microscopy. The crystallite size and cell parameters of sintered specimens were analyzed from XRD. The XRD of hydrothermally synthesized powders mostly matched with HAp with slight shifting due to Sr doping. However, some distinct Sr based compounds were also observed where Sr substitution is more that 50% of Ca. The XRD of sintered specimen showed increasing β-tricalcium phosphate (β-TCP) phase with Sr substitution. The sintered density of solid samples gradually increased from 3.04 g/cc to 3.50 g/cc and surface energy decreased with increasing Sr substitution. Similarly, microhardness, fracture toughness and nanohardness of solid samples found to be enhanced with Sr substitution. The elastic modulus gradually increased from 130 to 137 GPa for HAp and Sr substituted HAp (70% of Ca). The in vitro cytotoxicity of sintered specimen against mouse osteoblast cell line showed that all the samples were nontoxic. However cell proliferation found low for the solid samples containing more than 50% Sr substitution.
采用水热法从贻贝壳中合成了锶掺杂羟基磷灰石。生物陶瓷的掺杂，由生物资源加工而成，大多数尚未被探索。目的是了解锶（Sr）掺入对贝壳衍生羟基磷灰石（HAp）的相稳定性、烧结行为、力学性能和细胞毒性的影响。不同摩尔浓度的 Sr，分别为 Ca 的 10、30、50、70%，被取代到 HAp 中。合成的粉末在空气中于 1200°C 烧结。采用 X 射线衍射（XRD）、傅里叶变换红外光谱（FTIR）和高分辨率透射电子显微镜对合成的粉末和烧结的样品进行了表征。从 XRD 分析了烧结样品的晶粒尺寸和晶胞参数。水热合成粉末的 XRD 主要与 HAp 匹配，由于 Sr 掺杂略有偏移。然而，也观察到一些明显的基于 Sr 的化合物，其中 Sr 的取代量超过 Ca 的 50%。烧结样品的 XRD 显示随着 Sr 取代量的增加，β-磷酸三钙（β-TCP）相逐渐增加。固体样品的烧结密度逐渐从 3.04 g/cc 增加到 3.50 g/cc，表面能随着 Sr 取代量的增加而降低。同样，固体样品的显微硬度、断裂韧性和纳米硬度也随着 Sr 取代量的增加而提高。弹性模量从 HAp 和 Sr 取代的 HAp（70%的 Ca）的 130 逐渐增加到 137 GPa。烧结样品对小鼠成骨细胞系的体外细胞毒性表明，所有样品均无毒性。然而，对于含有超过 50% Sr 取代的固体样品，细胞增殖发现较低。
