Contrast agents are used in approximately 40% of all magnetic resonance imaging (MRI) procedures to improve the quality of the images based on the distribution and dynamic clearance of the agent. To date, all clinically approved contrast agents are Gd(III) coordination complexes that serve to shorten the longitudinal (T₁) and transverse (T₂) proton relaxation times of water. Recent interest in replacing Gd with biologically relevant metal ions such as Mn or Fe has led to increased interest in the aqueous coordination chemistry of their complexes. In this Account, we focus on high-spin Fe(III) complexes that have been recently reported as MRI contrast agents or probes in our laboratory.

中文翻译：

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基于 Fe(III) 的 MRI 探针的独特配位化学

大约 40% 的磁共振成像 (MRI) 程序中使用了造影剂，以根据造影剂的分布和动态清除来提高图像质量。迄今为止，所有临床批准的造影剂都是 Gd(III) 配位复合物，用于缩短水的纵向 (T ₁ ) 和横向 (T ₂ ) 质子弛豫时间。最近对用生物相关金属离子（例如 Mn 或 Fe）代替 Gd 的兴趣导致了对其配合物的水性配位化学的兴趣增加。在这个帐户中，我们专注于最近在我们的实验室中被报道为 MRI 造影剂或探针的高自旋 Fe(III) 配合物。