Faculty of Allied Health Sciences, Chettinad Hospital and Research Institute (CHRI), Chettinad Academy of Research & Education (CARE), Kelambakkam, Chennai, 603 103, India.
Department of Radiology, Chettinad Hospital and Research Institute (CHRI), Kelambakkam, Chennai, 603 103, India.
Sci Rep. 2017 Sep 11;7(1):11179. doi: 10.1038/s41598-017-11710-2.
In the present work, an attempt was made to engineer a mesoporous silica coated magnetic nanoparticles (MNF@mSiO) for twin mode contrast in magnetic resonance imaging (MRI) with reduced toxicity. Superparamagnetic manganese ferrite nanoparticles were synthesized with variable mesoporous silica shell thickness to control the water molecules interacting with metal oxide core. 178 nm was the optimum hydrodynamic diameter of mesoporous ferrite core-shell nanoparticles that showed maximum longitudinal relaxation time (T1) and transverse relaxation time (T2) in MRI due to the storage of water molecules in mesoporous silica coating. Besides the major role of mesoporous silica in controlling relaxivity, mesoporous silica shell also reduces the toxicity and enhances the bioavailability of superparamagnetic manganese ferrite nanoparticles. The in vitro toxicity assessment using HepG2 liver carcinoma cells shows that the mesoporous silica coating over ferrite nanoparticles could exert less toxicity compared to the uncoated particle.
在本工作中，尝试通过工程手段构建一种介孔硅包覆的磁性纳米颗粒（MNF@mSiO），以实现磁共振成像（MRI）的双模式对比，并降低其毒性。通过改变介孔硅壳层的厚度来合成超顺磁的锰铁氧体纳米颗粒，以控制与金属氧化物核心相互作用的水分子。178nm 的介孔铁氧核壳纳米颗粒具有最佳的水动力直径，在 MRI 中表现出最大的纵向弛豫时间（T1）和横向弛豫时间（T2），这是由于介孔硅涂层中储存了水分子。除了介孔硅在控制弛豫率方面的主要作用外，介孔硅壳还降低了超顺磁锰铁氧体纳米颗粒的毒性并提高了其生物利用度。通过 HepG2 肝癌细胞进行的体外毒性评估表明，与未包覆的颗粒相比，包覆在铁氧体纳米颗粒表面的介孔硅涂层的毒性更小。
