论文标题
在0.6 T
LED-based photo-CIDNP hyperpolarization enables 19F MR imaging and 19F NMR spectroscopy of 3-fluoro-DL-tyrosine at 0.6 T
论文作者
论文摘要
尽管19F在生物成像中充当无背景的分子标记具有很高的潜力，但是摩尔量的标记物质通常太小，无法实现19F MR成像或19F NMR光谱，具有足够高的信噪比（SNR）。超极化方法，例如基于偏高的超极化或动态核极化（DNP）可以显着改善SNR，但需要昂贵且复杂的样品制备以及去除有毒催化剂和溶剂。因此，我们将氟氨基酸3-氟-DL-酪氨酸与核黄素5'-单磷酸（FMN）的生物学兼容模型用作溶于D2O的生物团，溶于D2O，H2ODEST 3.4％。通过光化学诱导的动态核极化（Photo-CIDNP），可以将光能转化为19F核的超极化。我们使用了低成本的高动力蓝色导致照亮了传统使用的激光激发样本，这既有害又昂贵。我们首次介绍了使用低成本0.6 t台式MRI系统进行的超极化19F MRI和19F NMR的结果。该设备允许同时进行双通道1H/19F NMR。使用（0.94 mm）2间隔分辨率进行19F成像。这使样品中不同程度的超极化度实现了空间分辨率。我们估计基于光周期的19F信号增强在0.6 t时约为465。即使在多次激发后，FMN也没有漂白，因此可以通过平均超极化信号来进一步提高信号噪声比率。结果表明，易于使用的实验设置具有作为生物成像超极化研究的有效临床前工具具有很高的潜力。
Although 19F has high potential to serve as a background-free molecular marker in bioimaging, the molar amount of marker substance is often too small to enable 19F MR imaging or 19F NMR spectroscopy with a sufficiently high signal-to-noise ratio (SNR). Hyperpolarization methods such as parahydrogen-based hyperpolarization or dynamic nuclear polarization (DNP) can significantly improve the SNR, but require expensive and complex sample preparation and the removal of toxic catalysts and solvents. Therefore, we used the biologically compatible model of the fluorinated amino acid 3-fluoro-DL-tyrosine with riboflavin 5'-monophosphate (FMN) as a chromophore dissolved in D2O with 3.4% H2Odest. allowing to transform light energy into hyperpolarization of the 19F nucleus via photo-chemically induced dynamic nuclear polarization (photo-CIDNP). We used a low-cost high-power blue LED to illuminate the sample replacing traditionally used laser excitation, which is both potentially harmful and costly. For the first time, we present results of hyperpolarized 19F MRI and 19F NMR performed with a low-cost 0.6 T benchtop MRI system. The device allowed simultaneous dual channel 1H/19F NMR. 19F imaging was performed with a (0.94 mm)2 in-plane resolution. This enabled the spatial resolution of different degrees of hyperpolarization within the sample. We estimated the photo-CIDNP-based 19F signal enhancement at 0.6 T to be approximately 465. FMN did not bleach out even after multiple excitations, so that the signal-to-noise ratio could be further improved by averaging hyperpolarized signals. The results show that the easy-to-use experimental setup has a high potential to serve as an efficient preclinical tool for hyperpolarization studies in bioimaging.
