Adding a Second Quinol to a Redox-Responsive MRI Contrast Agent Improves Its Relaxivity Response to H2O2.
Adding a Second Quinol to a Redox-Responsive MRI Contrast Agent Improves Its Relaxivity Response to H2O2.
复制标题
在氧化还原响应 MRI 造影剂中添加第二种对苯二酚可改善其对 H2O2 的弛豫响应。
DOI：
--
复制
发表时间：
2017
影响因子：
4.6
通讯作者：
Christian R. Goldsmith
中科院分区：
文献类型：
--
作者：
Meng Yu;Meghan Ward;Alicja Franke;Stephen L Ambrose;Z. Whaley;Thomas Miller Bradford;J. Gorden;R. Beyers;R. Cattley;I. Ivanović‐Burmazović;D. Schwartz;Christian R. Goldsmith
活性氧的过量产生与多种健康疾病有关。无创监测体内氧化应激的能力可以为这些疾病的进展提供深入的了解，进而可以促进更好的诊断和治疗方案的开发。制备并表征了具有氧化还原活性配体 N,N'-双(2,5-二羟基苄基)-N,N'-双(2-吡啶基甲基)-1,2-乙二胺 (H4qtp2) 的单核 Mn(II) 配合物。先前制备的 Mn(II) 配合物与含有单个对苯二酚亚基的配体被发现对 H2O2 显示出适度的 T1 衍生弛豫响应。第二种氧化还原活性对苯二酚的引入既显着改善了复合物对H2O2的弛豫响应，又降低了传感器的细胞毒性，但使复合物更容易发生金属转移。添加 H2O2 会将醌亚基部分氧化为对醌，同时将 r1 从 5.46 mM-1 s-1 增加到 7.17 mM-1 s-1。配体的氧化使得更多的水分子与金属离子配位，这为弛豫率的增强提供了解释。双醌复合物仅被 H2O2 部分氧化，这归因于其作为抗氧化剂的活性；该配合物既可以催化降解超氧化物，又可以作为氢原子供体。
The overproduction of reactive oxygen species has been linked to a wide array of health disorders. The ability to noninvasively monitor oxidative stress in vivo could provide substantial insight into the progression of these conditions and, in turn, could facilitate the development of better diagnosis and treatment options. A mononuclear Mn(II) complex with the redox-active ligand N,N'-bis(2,5-dihydroxybenzyl)-N,N'-bis(2-pyridinylmethyl)-1,2-ethanediamine (H4qtp2) was made and characterized. A previously prepared Mn(II) complex with a ligand containing a single quinol subunit was found to display a modest T1-derived relaxivity response to H2O2. The introduction of a second redox-active quinol both substantially improves the relaxivity response of the complex to H2O2 and reduces the cytotoxicity of the sensor but renders the complex more susceptible to transmetalation. The addition of H2O2 partially oxidizes the quinol subunits to para-quinones, concomitantly increasing the r1 from 5.46 mM-1 s-1 to 7.17 mM-1 s-1. The oxidation of the ligand enables more water molecules to coordinate to the metal ion, providing an explanation for the enhanced relaxivity. That the diquinol complex is only partially oxidized by H2O2 is attributed to its activity as an antioxidant; the complex can both catalytically degrade superoxide and serve as a hydrogen atom donor.
登录
查看更多内容
影响因子：
16.6
作者：
Tsitovich, Pavel B.;Spernyak, Joseph A.;Morrow, Janet R.
通讯作者：
Morrow, Janet R.
影响因子：
4.6
作者：
Wang, Sen;Westmoreland, T. David
通讯作者：
Westmoreland, T. David
影响因子：
15
作者：
Loving GS;Mukherjee S;Caravan P
通讯作者：
Caravan P
影响因子：
2.9
作者：
Eskici, Goezde;Axelsen, Paul H.
通讯作者：
Axelsen, Paul H.
影响因子：
18.3
作者：
De Leon-Rodriguez, Luis M.;Lubag, Angelo Josue M.;Malloy, Craig R.;Martinez, Gary V.;Gillies, Robert J.;Sherry, A. Dean
通讯作者：
Sherry, A. Dean