The surface chemistry of engineered nanoparticles (ENPs) becomes more important as their size decreases and enters the nanometer-range. This review explains the fundamental properties of the surface chemistry of nanoparticles, and argues that their agglomeration and the formation of corona around them are natural processes that reduce surface energy. ENP agglomeration and surface corona formation are further discussed in the context of inhaled ENPs, as the lung is a major port of ENP entry to the body. The pulmonary surfactant layer, which the inhaled ENPs first encounter as they land on the lung surface, represents a unique environment with a variety of well-defined biomolecules. Many factors, such as hydrophobicity, surface charge of ENPs, protein/phospholipid concentrations of the alveolar lining fluid, etc. influence the complex processes of ENP agglomeration and corona formation in the alveolar lining fluid, and these events occur even before the ENPs reach the cells. We suggest that molecular dynamic simulations can represent a promising future direction for research of the behavior of inhaled ENPs, complementing the experimental approaches. Moreover, we want to remind biologists working on ENPs of the importance relationship between ENP surface energy and size.

中文翻译：

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吸入工程纳米颗粒的自然过程和表面能对聚集和电晕形成的作用

随着工程纳米粒子 (ENP) 尺寸减小并进入纳米范围，其表面化学变得更加重要。这篇综述解释了纳米颗粒表面化学的基本特性，并认为它们的团聚和周围电晕的形成是降低表面能的自然过程。ENP 团聚和表面冠形成在吸入 ENP 的背景下进一步讨论，因为肺是 ENP 进入人体的主要端口。吸入的 ENP 在降落到肺表面时首先遇到的肺表面活性剂层代表了一个具有各种明确生物分子的独特环境。许多因素，如 ENP 的疏水性、表面电荷、肺泡内壁液的蛋白质/磷脂浓度等，影响着肺泡内壁液中 ENP 团聚和电晕形成的复杂过程，并且这些事件甚至在 ENP 到达肺泡内膜之前就发生了。细胞。我们认为分子动力学模拟可以代表吸入 ENP 行为研究的一个有前途的未来方向，补充实验方法。此外，我们想提醒研究 ENP 的生物学家注意 ENP 表面能和尺寸之间的重要关系。