欧洲 (III) DOTA-四胺复合物作为氧化还原活性MRI传感器
S James Ratnakar1, Subha Viswanathan, Zoltan Kovacs
1Advanced Imaging Research Center, University of Texas Southwestern Medical Center, 5323 Harry Hines Boulevard, Dallas, Texas 75390, USA.
Journal of the American Chemical Society
|March 17, 2012
概括
开发了使用N-methylquinolinium的新型PARACEST氧化还原传感器. 一个传感器显示了与β-NADH显著的氧化还原反应"打开"切换,而另一个显示了pH敏感度.
科学领域:
- 化学生物学 化学生物学
- 生物医学工程 生物医学工程
- 分析化学 分析化学
背景情况:
- 化学交换和转移 (CEST) 成像是一种敏感的MRI技术.
- 开发有针对性的氧化还原传感器对于监测生物过程至关重要.
- 欧 (Eu3+) 复合物为传感应用提供独特的发光和磁性.
研究的目的:
- 设计和合成新的PARACEST (Paramagnetic CEST) 氧化还原传感器.
- 为了研究与NAD+/NADH模仿器功能化的Eu3+复合物的氧化还原反应.
- 为了评估这些新型传感器系统的pH敏感度.
主要方法:
- 合成Eu3+复合物,其中包括N-甲基基因组作为氧化还原活性组.
- 在氧化和还原状态下合成复合物的CEST属性的表征.
- 评估β-NADH降低对CEST信号的影响.
- 在生理范围内的pH依赖CEST效应的评估.
主要成果:
- 一个含有两种基因组的Eu3+复合物在其氧化形式中显示出几乎无声的CEST信号,该信号在与β-NADH减少时被显著激活.
- 一个单一基团的Eu3+复合物表现出减少的氧化还原反应能力,但在生理pH范围内表现出显著的pH敏感性.
- 在PARACEST传感器中,N-甲基素部分有效地作为氧化还原活性组起作用.
结论:
- 基于Eu3+复合体和NAD+/NADH模拟物的新型PARACEST氧化还原传感器已经成功开发出来.
- 设计的传感器显示出监测生物系统中氧化还原状态和pH值变化的潜力.
- 这些发现为基于MRI的先进诊断和研究工具开辟了道路.
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