Fe_2O_3@Au双模态纳米粒子在生物成像中的应用

Synthesis of Fe_2O_3@Au Dual Mode Nanoparticles for Bioimaging Applications

首先优化共沉淀法合成Fe_2O_3内核,然后利用交互盐酸羟胺还原法在Fe_2O_3内核上覆盖Au壳,得到粒径小于30nm的Fe_2O_3@Au核壳结构纳米粒子。使用紫外-可见(UV-Vis)光谱、透射电镜(TEM)及能谱仪(EDS)等方法对Fe_2O_3@Au纳米粒子进行表征,通过MTT法分析细胞毒性。利用核磁共振成像(MRI)及电子计算机X射线断层扫描(CT)造影成像对其性能进行表征。结果表明:5次包Au获得Fe_2O_3@Au纳米粒子的Au与Fe_2O_3摩尔比是1.07∶1,平均粒径为26.22±4.14nm,UV-Vis光谱吸收峰为521nm,0.72nmol/L纳米粒子与SW620人结直肠癌细胞作用24h之后,相对细胞活率高于对照组。驰豫效率为83.75L/(mmol·s),X射线吸收系数比碘高93%,将Fe_2O_3@Au纳米粒子应用于小鼠活体成像实验,结果表明Fe_2O_3@Au对小鼠肿瘤部位的MRI和CT信号均有较好的增强效果。

AfterFe2O3 core was synthesized by co-precipitation method, Fe2O3 @Au nanopartic prepared by decorating Au shell onto the surface of Fe2O3a core by a interactive hydro hydrochloride reduction strategy. The structure of the Fe2O3@ Au nanoparticles were charach UV-Vis spectrum, transmission electron microscopy （TEM） and energy-dispersive analysis （EDS） And their cytotoxicity was determined by MTT. After decorating Au shell onto the surface of Fe20 five times,the mass fraction of Au：Fe203 was 1.07：1 and the average particle size was 26.22±4.14 nm, meanwhile the UV-Vis absorption peak was 521 nm. It was found that the relative cell viability was higher than the control group after the SW620 human colorectal cancer cells were exposed to 0.72 nmol/L Fe2O3@Au nanoparticles for 24 h. The relaxation efficiency was 83. 75 L/（mmol. s）, and the X-ray absorption coefficient was 93% higher than that of iodine. The Fe2O3@Au nanoparticles were applied to in vivo imaging. The enhancement of MRI and CT signals in the tumor region were clearly observed.