Institute of Physical and Theoretical Chemistry and Center of Biomolecular Magnetic Resonance, Goethe University Frankfurt, Max-von-Laue-Str. 7, 60438 Frankfurt, Germany.
J Magn Reson. 2012 Feb;215:94-9. doi: 10.1016/j.jmr.2011.12.015. Epub 2011 Dec 30.
We have used liquid state ("Overhauser") Dynamic Nuclear Polarization (DNP) to significantly enhance the signal to noise ratio (SNR) of Magnetic Resonance Imaging (MRI). For the first time this was achieved by hyperpolarizing directly in the MRI-scanner field of 1.5 T in continuous flow mode and immediately delivering the hyperpolarized substance to the imaging site to ensure maximum contrast between hyperpolarized sample and sample at thermal polarization. We achieve a maximum absolute signal enhancement factor of 98; while the hyperpolarized sample is transported at a flow rate of up to 30 ml/h yielding an average flow speed up to 470 mm/s over a distance of approximately 80 mm. A spatial imaging resolution of 100 μm with a signal to noise ratio of 25 was achieved on the flowing sample. Application to MRI contrast enhancement or microfluidic imaging can be envisaged immediately.
我们使用液态（“Overhauser”）动态核极化（DNP）显著提高磁共振成像（MRI）的信号噪声比（SNR）。这是首次在 1.5T 的连续流动模式下在 MRI 扫描仪场中直接极化，并立即将极化物质输送到成像部位，以确保在热极化样品和样品之间具有最大对比度。我们实现了最大绝对信号增强因子为 98；同时，在 80mm 左右的距离内，将极化样品以高达 30ml/h 的流速输送，平均流速高达 470mm/s。在流动样品上实现了 100μm 的空间成像分辨率和 25 的信号噪声比。可以立即设想将其应用于 MRI 对比增强或微流控成像。
