载银珊瑚羟基磷灰石的制备及其对小鼠前成骨细胞的体外毒性研究

Preparation and in vitro cytotoxity of coral hydroxyapatite loaded with Ag^+

目的探讨负载不同浓度银离子的珊瑚羟基磷灰石(CHA)对小鼠前成骨细胞株体外毒性的影响。方法本实验采用CHA与AgNO3及NaC l复合,经真空冷冻干燥后制备载银CHA,通过扫描电镜和背散射电子探针研究了材料的显微结构,分析了银在材料表面的分布情况。采用能谱分析和X射线衍射鉴定了材料表面上的元素成分和物相组成,并采用MTT法评价了材料对小鼠前成骨细胞株MC3T3-E1的体外细胞毒性。结果载银CHA表面上的银颗粒呈散点分布。材料表面上的元素组成主要为Ca、P、Ag、C、O,且随着AgNO3浓度的升高,材料表明上的银颗粒晶体数量和Ag含量随之增加。载银材料的物相组分主要有CaCO3和羟基磷灰石,并含有少量的Ag2O、AgO和Ag3PO4。当AgNO3浓度≤1×10-4mol/L时,材料对小鼠前成骨细胞无毒性作用。结论负载银离子后的CHA的表面形貌和成分发生变化,且载银浓度小于1×10-4mol/L的材料对小鼠前成骨细胞无毒性作用。

Objective To prepare coral hydroxyapatite loaded with different concentration of Ag＋ and to detect its microstructure,chemical composition and cytotoxicity in vitro on preosteoblasts MC3T3-E1 from mouse.Methods Silver-loaded coral hydroxyapatites（Ag-CHA） with different concentrations of Ag＋ were prepared with AgNO3,followed by NaCl solution treatment and vacuum freeze-drying.The microstructure and silver distribution on the surface of Ag-CHAs were examined by scanning electron microscopy（SEM） and rutherford backscattering spectrometry（RBS）.The elemental and phase compositions were identified by energy dispersive spectrometer（EDS） and X-ray diffraction（XRD）.The cytotoxicity of Ag-CHAs with different Ag＋ concentrations on MC3T3-E1 subclone 14 was evaluated.Results Silver particles dispersedly adhered to the surface of Ag-CHAs.Its elemental composition mainly included Ca,P,Ag,C and O.The concentration of Ag and the number of silver particles were increased with the increase of Ag＋ concentration.Moreover,the phase compositions on surface of the Ag-CHAs were mainly CaCO3 and hydroxyapatite,with a little Ag2O,AgO and Ag3PO4.The Ag-CHA showed no cytotoxicity on preosteoblasts MC3T3-E1 from mouse,when the AgNO3 concentration was under 1×10-4 mol/L.Conclusions The microstruture and chemical composition of coral hydroxyapatite altered when coated by Ag＋.Silver-loaded CHA,of which Ag＋ concentration was lower than 1×10-4 mol/L,had no cytotoxicity on mouse preosteoblast.