Spin hyperpolarization techniques have enabled important advancements in preclinical and clinical MRI applications to overcome the intrinsic low sensitivity of nuclear magnetic resonance. Functionalized xenon biosensors represent one of these approaches. They combine two amplification strategies, namely, spin exchange optical pumping (SEOP) and chemical exchange saturation transfer (CEST). The latter one requires host structures that reversibly bind the hyperpolarized noble gas. Different nanoparticle approaches have been implemented and have enabled molecular MRI with 129Xe at unprecedented sensitivity. This review gives an overview of the Xe biosensor concept, particularly how different nanoparticles address various critical aspects of gas binding and exchange, spectral dispersion for multiplexing, and targeted reporter delivery. As this concept is emerging into preclinical applications, comprehensive sensor design will be indispensable in translating the outstanding sensitivity potential into biomedical molecular imaging applications.

中文翻译：

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用于 129Xe HyperCEST NMR 和 MRI 应用的纳米粒子造影剂。


自旋超极化技术使临床前和临床 MRI 应用取得了重要进展，克服了核磁共振固有的低灵敏度。功能化氙生物传感器代表了这些方法之一。它们结合了两种放大策略，即自旋交换光泵浦（SEOP）和化学交换饱和转移（CEST）。后一种需要可逆地结合超极化惰性气体的主体结构。不同的纳米颗粒方法已被实施，并使得 129Xe 分子 MRI 具有前所未有的灵敏度。这篇综述概述了 Xe 生物传感器的概念，特别是不同的纳米颗粒如何解决气体结合和交换、多重光谱色散和靶向报告基因传递的各个关键方面。随着这一概念逐渐进入临床前应用，全面的传感器设计对于将出色的灵敏度潜力转化为生物医学分子成像应用至关重要。