通过磁性交换合实现的 Cu(II) 2 准磁性化学交换和转移对比剂
1Department of Chemistry, Northwestern University , Evanston, Illinois 60208-3113, United States.
Journal of the American Chemical Society
|June 9, 2016
概括
磁交换合使铜复合体中的磁交换化学和转移 (PARACEST) 成为可能. 这一突破使新的PARACEST对比剂成为可能,扩大了成像的可能性.
科学领域:
- 无机化学
- 磁共振成像技术
- 超分子化学
背景情况:
- 超磁性化学交换和转移 (PARACEST) 是一个有前途的MRI对比剂技术.
- 具有较长电子放松时间 (τs) 的过渡金属离子对PARACET来说具有挑战性.
- 磁交换合为克服这些局限性提供了一个潜在的解决方案.
研究的目的:
- 证明在过渡金属离子中使用磁交换合器.
- 研究铜 (II) 复合物作为潜在的 PARACEST 剂.
- 探索超交换合对电子放松时间和CEST效应的影响.
主要方法:
- 两核铜 (II) 复合物与四核碳胺) 连接物和酸盐的合成和表征.
- 测量可变温度的磁性敏感性,以确定磁性合.
- 质子核磁共振 (NMR) 光谱测试,以评估 CEST 效应和线路扩展.
主要成果:
- 合成了一种双核铜 (II) 复合物[LCu (II) 2 (P2O7) ],表现出弱铁磁超交换合 (J = +2.69 ((5) 厘米 (-1)) 和S = 1基态.
- 磁性合显著缩短了电子放松时间 (τs),与二磁性模拟器相比,NMR线宽度提高了.
- 在铜 (II) 复合物中通过CEST效应观察到大量水信号强度下降了14%,但在控制铜模拟物中没有.
结论:
- 这项研究介绍了第一个基于铜的PARACEST磁共振对比剂.
- 磁交换合有效地增强了具有长t 的过渡金属离子中的 PARACEST.
- 这项工作扩大了适用于PARACET应用的金属离子范围.
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