Abstract

This paper proposed an engineered mesoporous silica-coated Fe₃O₄ nanoparticle, PVPMSFe, prepared by a sol-gel/surface-protected etching mechanism as an MRI T2 contrast agent. To this end, the structural characterization of the nanocomposite was performed by Fourier transform infrared spectroscopy (FT-IR), X-ray diffraction (XRD), Brunauer–Emmett–Teller (BET) method, VSM, thermogravimetric analysis (TGA), TEM, FESEM, and energy-dispersive X-ray scanning electron microscopy (EDS). The findings show that the synthesized nanocomposite has a mesoporous structure with an average particle size of 11.8 nm and excellent magnetization properties. The biocompatibility of PVPMSFe was investigated by MTT assay and hemolysis assay of red blood cells and the results indicate that PVPMSFe has favorable biocompatibility. Besides, the effect of PVPMSFe was assessed with MRI relaxivity measurement (T2 signal). Regarding the in vitro MRI relaxivity measurements outputs (r₂=144.4), PVPMSFe can attenuate the T2 signal of MRI, perfectly which makes it an efficient T2 contrast agent.

摘要

本文提出了一种工程介孔二氧化硅包覆的 Fe ₃ O ₄通过溶胶-凝胶/表面保护蚀刻机制制备的纳米颗粒 PVPMSFe 作为 MRI T2 造影剂。为此，纳米复合材料的结构表征通过傅里叶变换红外光谱 (FT-IR)、X 射线衍射 (XRD)、Brunauer-Emmett-Teller (BET) 方法、VSM、热重分析 (TGA)、TEM 、FESEM 和能量色散 X 射线扫描电子显微镜 (EDS)。研究结果表明，合成的纳米复合材料具有平均粒径为11.8 nm的介孔结构和优异的磁化性能。通过MTT法和红细胞溶血法研究了PVPMSFe的生物相容性，结果表明PVPMSFe具有良好的生物相容性。此外，通过 MRI 弛豫测量（T2 信号）评估 PVPMSFe 的效果。关于体外MRI 弛豫测量输出 ( r ₂ =144.4)，PVPMSFe 可以衰减 MRI 的 T2 信号，完美地使其成为有效的 T2 造影剂。