Miao Yashuang, Chen Peirong, Yan Miao, Xiao Jianmin, Hong Biao, Zhou Ke, Zhang Guilong, Qian Junchao, Wu Zhengyan
Department of Applied Chemistry, School of Science, Anhui Agricultural University, Hefei 230036, People's Republic of China.
Key Laboratory of High Magnetic Field and Ion Beam Physical Biology, Hefei Institutes of Physical Science, Chinese Academy of Sciences, Hefei 230031, People's Republic of China.
Biomed Mater. 2021 Apr 2;16(4). doi: 10.1088/1748-605X/abef54.
Single-mode magnetic resonance imaging (MRI) contrast agents (CAs) in clinical settings are easily disturbed by calcification, bleeding, and adipose signals, which result in inaccurate diagnoses. In this study, we developed a highly efficient-dual-mode MRI CA using an ultra-small gadolinium oxide-decorated magnetic iron oxide nanocrystal (GMIO). The gadolinium element could effectively alter the magnetic properties of the GMIO from soft-ferromagnetism to superparamagnetism. In addition, when the Gd/Fe ratio was 15% (designated as GMIO-2), the GMIO-2 possessed the best superparamagnetism and highest magnetism. Subsequently,andvalues of GMIO-2 were measured through a series of turbo spin-echo images and then multi-spin echo sequence, respectively. Based on this,andrelaxivities of GMIO-2 were calculated and were the highest (: 1.306 m Msand: 234.5 m Ms) when compared to other groups. The cytotoxicity of GMIO-2 was negligible under a wide range of dosages, thus exhibiting excellent cell biocompatibility. Moreover, GMIO-2 could quickly diffuse into cells, leading to its effective accumulation. The systemic delivery of GMIO-2 resulted in an excellent-dual-mode MRI contrast effect in kidneys, which is expected to improve the diagnosis of kidney lesions. Therefore, this work provides a promising candidate for the development of a-dual-mode MRI CA.
临床环境中的单模态磁共振成像（MRI）造影剂（CAs）容易受到钙化、出血和脂肪信号的干扰，从而导致诊断不准确。在本研究中，我们使用超小氧化钆修饰的磁性氧化铁纳米晶体（GMIO）开发了一种高效双模态MRI造影剂。钆元素可以有效地将GMIO的磁性从软铁磁性改变为超顺磁性。此外，当钆/铁比为15%（命名为GMIO-2）时，GMIO-2具有最佳的超顺磁性和最高的磁性。随后，分别通过一系列快速自旋回波图像和多自旋回波序列测量GMIO-2的纵向弛豫时间（T1）和横向弛豫时间（T2）值。基于此，计算出GMIO-2的弛豫率，与其他组相比，其弛豫率最高（T1：1.306 mM-1s-1；T2：234.5 mM-1s-1）。在广泛的剂量范围内，GMIO-2的细胞毒性可忽略不计，因此表现出优异的细胞生物相容性。此外，GMIO-2可以快速扩散到细胞中，导致其有效积累。GMIO-2的全身给药在肾脏中产生了优异的双模态MRI造影效果，有望改善肾脏病变的诊断。因此，这项工作为开发双模态MRI造影剂提供了一个有前景的候选物。
