Rhodium nanocatalysts and hyperpolarization - synthesis and production of biomedical contrast agents

Rh是一种金属，由于其独特的性质，具有各种催化应用。氢化反应就是反应的一个例子。在这项提议中，我的目标是合成有效的多相催化剂，用于代谢物的超极化。超极化是一种核磁共振技术，可以将信号增强四个数量级。一个主要的应用领域是医疗诊断。为了诊断，超极化的代谢物被注入生物体，其代谢转换被实时成像。一种超极化方法是基于对氢加氢。在仲氢中，核单重态可以填充到100%(100%自旋有序)。这种自旋顺序随后可以通过氢化反应转换为可观察到的磁化。对于代谢物，可以实现超过1万倍的信号增强。对位加氢过程主要使用均相催化剂。在超极化实验的时间尺度上，均相催化剂很难分离，并引发了毒性问题。本提案中所追求的多相催化剂的合成将导致产生用于医学诊断的清洁代谢物的可能性。这是通过设计能够产生高水平超极化的粒子来实现的，并且可以从感兴趣的分子中过滤掉。

Rhodium is a metal with a variety of catalytic applications due to its unique properties. One example of a reaction is the hydrogenation. In this proposal I am aiming to achieve the goal of synthesizing potent heterogeneous catalysts which are going to be utilized for the hyperpolarization of metabolites. Hyperpolarization is a nuclear magnetic resonance (NMR) technique which enhances signals over four orders of magnitude. A main field of application is the medical diagnostics. For diagnostics, hyperpolarized metabolites are injected into an organism and their metabolic conversion is imaged in realtime. One hyperpolarization method is based on the hydrogenation with para-hydrogen. In para-hydrogen, a nuclear singlet state can be populated up to 100% (100% spin order). This spin order can subsequently be converted into observable magnetization by means of a hydrogenation reaction. For metabolites, more than 10 000fold signal enhancements can be achieved. Mainly homogeneous catalysts are being utilized for the para-hydrogenation process. Homogeneous catalysts can hardly be separated on the timescale of a hyperpolarization experiment and raise toxicity concerns. The synthesis of a heterogeneous catalyst as pursued in this proposal will lead to possibilities to create clean metabolites for medical diagnostics. This is achieved by designing particles that generate high levels of hyperpolarization and can be filtered off from a molecule of interest.