Wang Luning, Potter William M, Zhao Qun
Center for Magnetic Resonance Research, University of Minnesota, Twin Cities, Minneapolis, MN, USA.
Contrast Media Mol Imaging. 2015 Jan-Feb;10(1):43-50. doi: 10.1002/cmmi.1601. Epub 2014 Apr 25.
Along with the development of modern imaging technologies, contrast agents play increasingly important roles in both clinical applications and scientific research. Super-paramagnetic iron oxide (SPIO) nanoparticles, a negative contrast agent, have been extensively used in magnetic resonance imaging (MRI), such as in vivo labeling and tracking of cells. However, there still remain many challenges, such as in vivo quantification of SPIO nanoparticles. In this work, an MR phase gradient-based method was proposed to quantify the SPIO nanoparticles. As a calibration, a phantom experiment using known concentrations (10, 25, 50, 100, 150 and 250 µg/ml) of SPIO was first conducted to verify the proposed quantification method. In a following in vivo experiment, C6 glioma cells labeled with SPIO nanoparticles were implanted into flanks of four mice, which were scanned 1-3 days post-injection for in vivo quantification of SPIO concentration. The results showed that the concentration of SPIO nanoparticles could be determined in both phantom and in vivo experiments using the developed MR phase gradients approach.
随着现代成像技术的发展，造影剂在临床应用和科学研究中都发挥着越来越重要的作用。超顺磁性氧化铁（SPIO）纳米颗粒作为一种阴性造影剂，已广泛应用于磁共振成像（MRI），如细胞的体内标记和追踪。然而，仍然存在许多挑战，如SPIO纳米颗粒的体内定量。在这项工作中，提出了一种基于磁共振相位梯度的方法来定量SPIO纳米颗粒。作为校准，首先进行了使用已知浓度（10、25、50、100、150和250μg/ml）的SPIO的体模实验，以验证所提出的定量方法。在接下来的体内实验中，将用SPIO纳米颗粒标记的C6胶质瘤细胞植入四只小鼠的侧腹，在注射后1-3天对其进行扫描，以对SPIO浓度进行体内定量。结果表明，使用所开发的磁共振相位梯度方法，可以在体模和体内实验中确定SPIO纳米颗粒的浓度。
