超极化磁共振成像(MRI)造影剂正在彻底改变生物医学成像领域。超极化Xe-129最近被FDA批准为用于功能性肺成像感测的可吸入MRI造影剂。尽管在研究环境中取得了成功,现代Xe-129超极化器价格昂贵(高达100万美元),大,复杂的现场和操作。此外,Xe-129传感需要专门的MRI硬件,这在临床MRI扫描仪上是不常见的。这里,我们证明了质子超极化丙烷气体可以按需使用一次性生产,手持,临床尺度超极化通过副氢诱导极化,它依赖于仲氢作为超极化的来源。该装置由连接到气体混合物储存罐的非均相催化反应器组成,所述气体混合物储存罐包含加压超极化前体:丙烯和对氢(10巴总压力)。一旦启动了存储罐的内置流量阀,前体从罐中喷射到反应堆中,超极化丙烷气流从反应器中喷出。证明了该设备的强大操作,可在宽范围的操作压力和气体流速下产生1.2%的质子感测极化。我们证明了丙烯/对氢气体混合物可以在单指数衰减时间常数为6.0±0.5天的储存罐中保留几天的效力,这受到储存容器中对氢单线态自旋态的寿命的限制。在距试剂/设备制备地点100英里的3T临床MRI扫描仪上的体模成像以及使用0.35T临床MRI扫描仪切除的猪肺的通气成像中,证明了所生产的传感剂的实用性。设备组件的成本低于35美元,我们设想大规模生产可以将其降低到5美元以下。超极化器装置可以重复使用,回收,或处置。
Hyperpolarized magnetic resonance imaging (MRI) contrast agents are revolutionizing the field of biomedical imaging. Hyperpolarized Xe-129 was recently FDA approved as an inhalable MRI contrast agent for functional lung imaging sensing. Despite success in research settings, modern Xe-129 hyperpolarizers are expensive (up to $1M), large, and complex to site and operate. Moreover, Xe-129 sensing requires specialized MRI hardware that is not commonly available on clinical MRI scanners. Here, we demonstrate that proton-hyperpolarized propane gas can be produced on demand using a disposable, hand-held, clinical-scale hyperpolarizer via parahydrogen-induced polarization, which relies on parahydrogen as a source of hyperpolarization. The device consists of a heterogeneous catalytic reactor connected to a gas mixture storage can containing pressurized hyperpolarization precursors: propylene and parahydrogen (10 bar total pressure). Once the built-in flow valve of the storage can is actuated, the precursors are ejected from the can into a reactor, and a stream of hyperpolarized propane gas is ejected from the reactor. Robust operation of the device is demonstrated for producing proton sensing polarization of 1.2% in a wide range of operational pressures and gas flow rates. We demonstrate that the propylene/parahydrogen gas mixture can retain potency for days in the storage can with a monoexponential decay time constant of 6.0 ± 0.5 days, which is limited by the lifetime of the parahydrogen singlet spin state in the storage container. The utility of the produced sensing agent is demonstrated for phantom imaging on a 3 T clinical MRI scanner located 100 miles from the agent/device preparation site and also for ventilation imaging of excised pig lungs using a 0.35 T clinical MRI scanner. The cost of the device components is less than $35, which we envision can be reduced to less than $5 for mass-scale production. The hyperpolarizer device can be reused, recycled, or disposed.