Two major hurdles in nanomedicine are the limited strategies for synthesizing stealth nanoparticles and the poor efficacy of the nanoparticles in translocating across the blood brain barrier (BBB). Here we examined the uptake and transcytosis of iron oxide nanoparticles (IONPs) grafted with biomimetic phosphorylcholine (PC) brushes in an in vitro BBB model system, and compared them with bare, PEG or PC–PEG mixture grafted IONPs. Hyperspectral imaging indicated IONP co-localization with cells. Quantitative analysis with total reflection X-ray fluorescence spectrometry showed that after 24 h, 78% of PC grafted, 68–69% of PEG or PC–PEG grafted, and 30% of bare IONPs were taken up by the BBB. Transcytosis of IONPs was time-dependent and after 24 h, 16–17% of PC or PC–PEG mixture grafted IONPs had passed the BBB model, significantly more than PEG grafted or bare IONPs. These findings point out that grafting of IONPs with PC is a viable strategy for improving the uptake and transcytosis of nanoparticles.

中文翻译：

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摄取和在官能化的超顺磁性氧化铁纳米颗粒的转胞吞作用的体外血脑屏障模型†

纳米药物的两个主要障碍是合成隐形纳米粒子的策略有限，以及纳米粒子跨血脑屏障（BBB）转运的不良功效。在这里，我们检查在与磷酰胆碱仿生（PC）接枝电刷氧化铁纳米颗粒（IONPs）的摄取和胞转体外BBB模型系统，并将其与裸接的PEG或PC-PEG混合物接枝的IONP进行比较。高光谱成像表明IONP与细胞共定位。用全反射X射线荧光光谱法进行的定量分析表明，BBB吸收了24小时后接枝的PC的78％，PEG或PC-PEG接枝的68-69％，以及裸IONP的30％。IONP的胞吞作用是时间依赖性的，在24小时后，移植PC或PC-PEG混合物的IONP通过BBB模型的比例为16–17％，明显多于PEG移植或裸IONP。这些发现指出，将IONP与PC接枝是改善纳米颗粒摄取和转胞作用的可行策略。