高溶解的三基酸Gd(III) 复合物具有增加的水合数,快速的水交换,缓慢的电子放松和高的放松性
Eric J Werner1, Stefano Avedano, Mauro Botta
1College of Chemistry, University of California, Berkeley, California 94720-1460, USA.
Journal of the American Chemical Society
|January 31, 2007
概括
具有TACN封闭的高度溶解的加多 (Gd) 复合物显示出对MRI对比剂的优越放松性. 这些新的复合物,包括三个水分子,实现了一些已知的最高的放松性低分子量剂.
科学领域:
- * 无机化学 无机化学
- * 医学化学 医学化学
- * 材料科学 材料科学
背景情况:
- * 加多 (Gd(III)) 复合物作为磁共振成像 (MRI) 中的对比剂至关重要.
- * 提高低分子量Gd复合物的放松性和可溶性是提高诊断疗效的关键.
- * 设计具有多个内部球体水分子的复合体可以显著提高放松性.
研究的目的:
- * 设计,合成和表征新型的TACN封顶的三氧酸-Gd (III) 复合物.
- * 调查这些新的Gd(III) 综合体的放松性和水协调性.
- * 探索这些复合物作为高性能MRI对比剂的潜力.
主要方法:
- *用于合理复杂设计的分子力学建模.
- *TACN顶级的三氧酸-Gd (III) 复合物的合成和特征.
- * 在20 MHz,298 K. 的放松度测量.
- *发光光谱测试以确认水中的协调.
主要成果:
- *成功设计和合成高可溶性TACN顶层三氧酸-Gd (III) 复合物.
- * 测量放松度为13.1和12.5mM-1s-1,是低分子量Gd复合体中最高的.
- *结果与三个协调的水分子,快速的水交换和长的电子放松时间一致.
- *发光度测量证实了HOPO系列中协调的水分子的数量.
结论:
- * 设计的TACN顶层复合体表现出特殊的放松性,这是由于有利的协调特性所驱动的.
- *这些复合物代表了低分子量MRI对比剂的开发的重大进步.
- *这项研究验证了使用计算建模和发光光谱学来表征这种药物.
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