Institute of Medical Engineering, Graz University of Technology, Graz, Austria.
Centre de Biophysique Moléculaire, CNRS, Rue Charles Sadron, 45071, Orléans Cedex 2, France.
Chemistry. 2019 Jun 21;25(35):8236-8239. doi: 10.1002/chem.201901157. Epub 2019 May 21.
Many smart magnetic resonance imaging (MRI) probes provide response to a biomarker based on modulation of their rotational correlation time. The magnitude of such MRI signal changes is highly dependent on the magnetic field and the response decreases dramatically at high fields (>2 T). To overcome the loss of efficiency of responsive probes at high field, with fast-field cycling magnetic resonance imaging (FFC-MRI) we exploit field-dependent information rather than the absolute difference in the relaxation rate measured in the absence and in the presence of the biomarker at a given imaging field. We report here the application of fast field-cycling techniques combined with the use of a molecular probe for the detection of Zn to achieve 166 % MRI signal enhancement at 3 T, whereas the same agent provides no detectable response using conventional MRI. This approach can be generalized to any biomarker provided the detection is based on variation of the rotational motion of the probe.
许多智能磁共振成像 (MRI) 探针通过调节其旋转相关时间对生物标志物做出响应。这种 MRI 信号变化的幅度高度依赖于磁场，并且在高磁场 (>2 T) 下响应会急剧下降。为了克服在高场下响应探针效率的损失，我们利用快速场循环磁共振成像 (FFC-MRI) 技术来利用场依赖性信息，而不是在给定的成像场中测量生物标志物存在和不存在时的弛豫率的绝对差异。我们在这里报告了快速场循环技术的应用，结合使用用于检测 Zn 的分子探针，在 3 T 时实现了 166%的 MRI 信号增强，而使用传统 MRI 则无法检测到相同的试剂。只要检测基于探针旋转运动的变化，这种方法就可以推广到任何生物标志物。
