Russell H. Morgan Department of Radiology and Radiological Science, Johns Hopkins University School of Medicine, Baltimore, Maryland, 21287, USA.
F. M. Kirby Research Center for Functional Brain Imaging, Kennedy Krieger Institute, Baltimore, Maryland, USA.
Chemistry. 2018 May 17;24(28):7235-7242. doi: 10.1002/chem.201800882. Epub 2018 Apr 26.
Chemical exchange saturation transfer (CEST) magnetic resonance imaging (MRI) is an innovative molecular imaging technique in which contrast agents are labeled by saturating their exchangeable proton spins by radio-frequency irradiation. Salicylic acid and its analogues are a promising class of highly sensitive, diamagnetic CEST agents. Herein, polymeric agents grafted with salicylic acid moieties and a known high-affinity ligand targeting prostate-specific membrane antigen in approximately 10:1 molar ratio were synthesized to provide sufficient MRI sensitivity and receptor specificity. The proton-exchange properties of the contrast agent in solution and in an experimental murine model are reported to demonstrate the feasibility of receptor-targeted CEST MRI of prostate cancer. Furthermore, the CEST imaging data were validated with an In-labeled analogue of the agent by in vivo single photon emission computed tomographic imaging and tissue biodistribution studies.
化学交换饱和传递（CEST）磁共振成像（MRI）是一种创新的分子成像技术，其中对比剂通过射频辐射饱和其可交换质子自旋进行标记。水杨酸及其类似物是一类很有前途的高灵敏度、抗磁性 CEST 试剂。本文合成了接枝有水杨酸部分和已知靶向前列腺特异性膜抗原的高亲和力配体的聚合物试剂，以提供足够的 MRI 灵敏度和受体特异性。报道了该对比剂在溶液中和实验性小鼠模型中的质子交换性质，以证明前列腺癌受体靶向 CEST MRI 的可行性。此外，还通过体内单光子发射计算机断层扫描成像和组织生物分布研究，用该试剂的 In 标记类似物对 CEST 成像数据进行了验证。
