在二价和复合体中的胺基和基组的比较paraCEST效应,三基连接体的三基复合体
Suvam Kumar Panda1, Julia Torres2, Carlos Kremer2
1Indian Institute of Technology Bhubaneswar, Khordha, Odisha 752050, India. aksingh@iitbbs.ac.in.
Dalton transactions (Cambridge, England : 2003)
|September 12, 2023
概括
和复合体与TMTP连接体显示了MRI对比剂的优秀paraCEST信号. 这些富含胺的复合物显示出先进的磁共振成像应用的巨大潜力.
科学领域:
- 协调化学 协调化学
- 材料科学 材料科学 材料科学
- 生物医学成像技术 生物医学成像技术
背景情况:
- ParaCEST剂对于增强MRI对比度至关重要.
- 开发新的配体是提高paraCEST剂性能的关键.
- 金属复合物为成像应用提供可调节的特性.
研究的目的:
- 作为潜在的ParaCESTMRI对比剂,研究具有TDTA和TMTP连接体的Co (II) 和Ni (II) 复合体.
- 评估这些复合体中氧和胺质子的CEST活性.
- 评估合成复合物的稳定性和结构性质.
主要方法:
- 用TDTA和TMTP连接体合成和表征Co (II) 和Ni (II) 复合体.
- 用X射线晶体学来确定复杂的结构.
- 核磁共振 (NMR) 光谱检测质子的存在.
- 用于稳定常数的测定而进行的电位计定位.
- 可变pH和脉冲功率的研究. paraCEST研究.
主要成果:
- 由于胺质子参与,TMTP连接体复合体 (Co(II) 和Ni(II)) 显示出出色的paraCEST信号.
- 在TDTA连接体中,基组是被动的,而胺基组在CEST中是活性的.
- X射线结构揭示了Co (七坐标) 和Ni (六坐标) 复合体的不同协调几何结构.
- 综合体在各种条件下 (pH,温度,竞争离子) 显示出良好的稳定性.
结论:
- 与TMTP连接体的Co (II) 和Ni (II) 复合体是基于paraCEST的MRI对比剂的有希望的候选者.
- 可交换质子的数量和类型显著影响CEST信号效率.
- 结构和稳定性数据支持它们在体内应用的潜力.
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