微米级椭球形掺铕羟基磷灰石的发光和细胞毒性研究

doi:10.15541/jim20150662

摘要/Abstract

摘要：

利用碳酸钙模板和离子交换过程成功制备了一种新型掺铕羟基磷灰石微球。通过扫描电子显微镜(SEM)、X射线衍射(XRD)、感应耦合等离子体(ICP)、光致发光谱和体外MTT实验对微球物化性能、发光性和细胞毒性进行了表征。研究结果显示: 掺铕羟基磷灰石微球呈椭球形, 直径约为2.5 μm, 长度约为7 μm, 并具有刺猬状表面; 在晶体结构上与纯相六方羟基磷灰石相同, 具有高结晶性; 铕离子成功进入羟基磷灰石晶相。同时, 研究还表明该掺铕羟基磷灰石颗粒在紫外光激发下显示出红色荧光。光致发光光谱表明铕离子的⁵D₀→⁷F_1-4跃迁明显在光致发光活性中具有重要作用。体外细胞毒性实验结果显示: MC3T3-E1小鼠胚胎骨细胞在掺铕羟基磷灰石浸提液中能够持续增殖, 没有细胞形态上的变化, 并且细胞相对增值率计算结果表明该掺铕羟基磷灰石细胞毒性等级为1级。

关键词: 羟基磷灰石, 生物材料, 铕掺杂, 椭球形, 荧光性

Abstract:

A novel europium (Eu³⁺)-doped hydroxyapatite microspheres (Eu-HApMs) was successfully prepared via the calcium carbonate template and ion exchange process. The physicochemical, luminescent and cytotoxic properties of the prepared Eu-HApMs powders were investigated by the Scanning Electron Microscope (SEM), X-ray Diffraction (XRD), Inductively Coupled Plasma (ICP), and MTT assays in vitro. Results showed that Eu-HApMs particles exhibited an ellipsoidal morphology with diameters of about 2.5 μm and lengths of about 7 μm with a hedgehog-like surface. Besides, the pure hexagonal phase of hydroxyapatite with high crystallinity of Eu-HApMs and successful doping of Eu³⁺ ions into HApMs were revealed. The present study showed that the Eu-HApMs powders actually displayed red fluorescence under ultraviolet (UV) irradiation. It was evident that the ⁵D₀→⁷F_1-4 transitions of Eu (III) ions played a key role in the photoluminescence (PL) activity. Finally, the MTT assay results revealed the continuous proliferation and no morphological change of MC3T3-E1 cells co-cultured with the extracts of Eu-HApMs powders and the calculated relative growth rate (RGR) indicating the cytotoxicity grade at level 1.

Key words: hydroxyapatite, biomaterials, europium-doped, ellipsoidal, fluorescence

中图分类号:

TQ174

马铭, 卢伟鹏, 曹霄峰, 毛克亚, 郭燕川. 微米级椭球形掺铕羟基磷灰石的发光和细胞毒性研究[J]. 无机材料学报, 2016, 31(8): 890-896.

MA Ming, LU Wei-Peng, CAO Xiao-Feng, MAO Ke-Ya, GUO Yan-Chuan. Luminescent and Cytotoxic Characteristics of an Ellipsoidal and Microsized Europium (Eu)-doped Hydroxyapatite[J]. Journal of Inorganic Materials, 2016, 31(8): 890-896.

图/表 8

Table 1 Correlation between RGR and grade of cytotoxicity

Relative growth rate/%	Grade of cytotoxicity	Cytotoxicity
≥100	0	No
75-99	1	No
50-74	2	Analyzed with the cell morphology
5-49	3	Yes
1-24	4	Yes
0	5	Yes

Fig. 1 SEM images of CCMs (a), HApMs (b) and EuHApMs (c: 1 h; d: 7 h)

Fig. 2 XRD patterns of CCMs (a), HApMs (b) and Eu- HApMs (c)

Fig. 3 XRD patterns of the transformation process of CCMs to HAPMs

Fig. 4 ICP results of the ion-doping process

Fig. 5 Emission (a) and exciation (b) spectra of the ions-doped HAPMs Inset is the corresponding photograph under ultraviolet (365 nm) irradiation

Table 2 Results of the cytotoxicity test

Date/d	OD ( ± s)	RGR/%	Grade
1	0.165±0.044	132.48	0
3	0.819±0.044	110.05	0
5	1.376±0.091	79.90	1
7	1.531±0.050	89.54	1

Fig. 6 (a) The MC3T3-E1 cells co-cultured with the extracts of Eu-HApMs powders for different culture time; (b) MTT results for tested Eu-HApMs for different culture time*P<0.05, **P<0.01

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