欧欧 ((III) 宏环复合物与酒精悬挂组作为化学交换和转移剂
Mark Woods1, Donald E Woessner, Piyu Zhao
1Macrocyclics, 2110 Research Row, Suite 425, Dallas, Texas 75235, USA.
Journal of the American Chemical Society
|August 3, 2006
概括
偏磁性兰坦化物复合物显示出作为MRI对比剂的前景. 然而,具有基乙基组的欧 (III) 复合物由于微小的化学转移和快速的水交换而具有有限的效用.
科学领域:
- 磁共振成像是一种磁共振成像技术.
- 无机化学 无机化学 有机化学
- 生物医学工程 生物医学工程
背景情况:
- 与可交换的质子配合的偏磁性兰化物 (III) 复合物是MRI相比二磁性分子更有利的化学交换和转移 (CEST) 剂.
- 研究提高这些CEST剂的灵敏度的方法对于推进MRI应用至关重要.
研究的目的:
- 为了研究用基乙基组功能化的欧(III) 宏环复合物的CEST特性.
- 评估这些复杂物作为MRI对比剂的潜力.
主要方法:
- 合成和表征欧(III) 宏环复合物与附加的基乙基组.
- 使用NMR布洛赫理论分析CEST光谱,以确定质子交换率.
- 逐步将水添加到酸溶液中,以研究对质子交换的影响.
主要成果:
- 不对称的复合体EuCNPHC3+在其CEST频谱中表现出每个质子池的五个不同的峰值.
- 与Eu3+结合的基团和散装水之间的质子交换在干甲中缓慢,但在添加水时增加.
- 在纯水中,质子交换太快,无法观察到CEST效应.
结论:
- 对于CEST成像,这些欧 (III) 复合物的实用性受限于从基乙基联结物中进行的有限化学转移.
- 可交换基质子的小Deltaomega值进一步限制了它们在CESTMRI中的应用.
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