Medical Imaging Key Laboratory of Sichuan Province and School of Medical Imaging, Affiliated Hospital of North Sichuan Medical College, Nanchong, 637000, People's Republic of China.
Department of Radiology, First People's Hospital of Neijiang, Neijiang 641000, People's Republic of China.
Int J Nanomedicine. 2021 Jan 8;16:201-211. doi: 10.2147/IJN.S271461. eCollection 2021.
PEGylated superparamagnetic iron oxide (SPIO) is the most promising alternatives to gadolinium-based contrast agents (GBCAs) in MRI. This paper is to explore the imaging effects of PEGylated SPIO, which is influenced by particle sizes and surface polyethylene glycol (PEG) coating, using as MRI contrast agents at different magnetic field intensities.
Firstly, nine PEGylated monocrystalline SPIO nanoparticles with different nanocrystal sizes and different molecular weights PEG coating were prepared, and then physical and biological properties were analyzed. Finally, MRI imaging in vivo was performed to observe the imaging performance.
Nine PEGylated monocrystalline SPIO nanoparticles have good relaxivities, serum stability, and biosecurity. At the same time, they show different imaging characteristics at different magnetic field intensities. Eight-nanometer SPIO@PEG5k is an effective contrast agent at 3.0 T ( / = 14.0), is an ideal - dual-mode contrast agent at 1.5 T ( / = 6.52), and is also an effective contrast agent at 0.5 T ( / = 2.49), while 4-nm SPIO@PEG5k is a - dual-mode contrast agent at 3.0 T ( / = 5.24), and is a useful contrast agent at 0.5 T ( / = 1.74) and 1.5 T ( / = 2.85). MRI studies in vivo at 3.0 T further confirm that 4-nm SPIO@PEG5k displays excellent - dual-mode contrast enhancement, whereas 8-nm SPIO@PEG5k only displays contrast enhancement.
PEGylated SPIOs with different nanocrystal sizes and PEG coating can be used as , , or - dual-mode contrast agents to meet the clinical demands of MRI at specific magnetic fields.
聚乙二醇（PEG）修饰的超顺磁性氧化铁（SPIO）是目前最有希望替代磁共振成像（MRI）中钆基对比剂（GBCA）的材料。本研究旨在探讨不同粒径和表面聚乙二醇（PEG）修饰的 PEG 修饰 SPIO 作为 MRI 对比剂在不同磁场强度下的成像效果。
首先，制备了 9 种具有不同纳米晶体尺寸和不同分子量 PEG 修饰的 PEG 修饰单晶 SPIO 纳米颗粒，并对其理化性质进行了分析。最后，进行了体内 MRI 成像观察其成像性能。
9 种 PEG 修饰单晶 SPIO 纳米颗粒具有良好的弛豫率、血清稳定性和生物安全性。同时，它们在不同磁场强度下表现出不同的成像特征。8nm SPIO@PEG5k 在 3.0T（ / = 14.0）下是一种有效的 T1 加权对比剂，在 1.5T（ / = 6.52）下是一种理想的 T1/T2 双模式对比剂，在 0.5T（ / = 2.49）下也是一种有效的 T2 加权对比剂，而 4nm SPIO@PEG5k 在 3.0T（ / = 5.24）下是一种 T1/T2 双模式对比剂，在 0.5T（ / = 1.74）和 1.5T（ / = 2.85）下是一种有用的 T2 加权对比剂。3.0T 体内 MRI 研究进一步证实，4nm SPIO@PEG5k 显示出优异的 T1/T2 双模式对比增强，而 8nm SPIO@PEG5k 仅显示 T1 加权对比增强。
不同纳米晶体尺寸和 PEG 修饰的 PEG 修饰 SPIO 可作为 T1、T2 或 T1/T2 双模式对比剂，以满足特定磁场下 MRI 的临床需求。
