MRI on fluorine-19 is an effective tool for imaging and monitoring phagocytic cells (macrophages, stem cells, etc.) This method is based on the visualization of perfluorocarbon (PFC) emulsions, which nanoparticles undergo endocytosis by macrophages in an organism. The liver and spleen are main places of emulsion accumulation, but not the only ones. The purpose of our study was to identify organs (besides the liver and spleen) that can accumulate PFC emulsions sufficiently for 19F MRI. We studied the biodistribution of PFC emulsion in rats after two different methods of its introduction into an organism (intravenously and intraperitoneally). It was shown that PFC emulsions are accumulated by the thymus and the nearest lymph nodes in the sufficient amount (around 2% of the total intraperitoneally injected dose) to be visualized. It turned out that PFC emulsion is accumulated more in thymus after intraperitoneal injection in comparison with intravenous injection. This is due to the differences in the capture of emulsion by macrophages when it is initially injected into the bloodstream or the abdomen.

中文翻译：

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大鼠全氟化碳乳剂生物分布的新方面：胸腺成像

Fluorine-19 的 MRI 是对吞噬细胞（巨噬细胞、干细胞等）进行成像和监测的有效工具。该方法基于全氟化碳 (PFC) 乳液的可视化，纳米粒子在生物体中被巨噬细胞吞噬。肝脏和脾脏是乳汁积聚的主要场所，但不是唯一的场所。我们研究的目的是确定可以为 19F MRI 充分积累 PFC 乳液的器官（除了肝脏和脾脏）。我们研究了 PFC 乳液在将其引入生物体的两种不同方法（静脉内和腹膜内）后在大鼠中的生物分布。结果表明，胸腺和最近的淋巴结以足够的量（约 2% 的腹腔内注射总剂量）积聚了 PFC 乳剂以进行可视化。结果表明，与静脉注射相比，腹​​腔注射后PFC乳剂在胸腺中的积累更多。这是由于巨噬细胞最初注入血流或腹部时捕获乳液的差异。