含有酸盐或氧氨酸附加的胺基酸盐的MRI探针和封闭水的协调站点
Roy Cineus1, Samira M Abozeid2, Gregory E Sokolow1
1Department of Chemistry, University at Buffalo, The State University of New York Amherst, New York 14260, United States.
Inorganic chemistry
|September 25, 2023
概括
新的铁 (III) 复合物与五牙酸连接体作为T1MRI对比剂. 这些探针在体内表现出有效的稳定性和增强的对比度,不同的衍生物具有不同的清除途径.
科学领域:
- 无机化学 无机化学 有机化学
- 磁共振成像 (MRI) 是一种磁共振成像技术.
- 对比剂开发对比剂开发
背景情况:
- 铁 (III) 复合物被探索为T1MRI对比剂.
- 现有的线性酸盐往往缺乏足够的稳定性或水协调.
- 五联体为稳定的六坐标复合体提供了一个有前途的替代方案.
研究的目的:
- 对于T1MRI来说,要对新型Fe(III) 复合物与五联体进行特征化.
- 为了评估它们的稳定性,水交换特性和放松性.
- 评估它们的体内性能和药理动力学特征.
主要方法:
- 合成和Fe (III) 复合物的结构特征.
- pH电位计定位和电子吸收光谱学.
- 可变温度17O核磁共振光谱仪用于水交换.
- 质子放松性测量和竞争性结合研究 (EDTA).
- 在BALB/c小鼠中的体内T1加权MRI和药理动力学分析.
主要成果:
- 合成水溶性Fe(III) 复合物与氧二胺 (Fe(L2) 和基酸 (Fe(L3)) 连接物.
- 证明了依赖pH的质子化和电子光谱变化,与连接体去质子化一致.
- 观察到缓慢的内部球体水交换和pH取决于放松度.
- 实现了高的有效稳定常数 (log K > 20) 和动力惰性.
- 在小鼠的T1加权MRI中,Fe (L2) 和Fe (L3) 增强了对比度.
- Fe(L2) 呈现出混合的/肝胆清除,而Fe(L3) 显示出类似Gd(III) 的清除.
结论:
- 五牙Fe (III) 复合物是有效的T1MRI对比剂,具有可调节的特性.
- 这些复合物表现出良好的稳定性和体内性能.
- 独特的药物动力学特征表明有针对性应用的潜力.
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