Nanomaterials have been widely used in the design of drug delivery platforms. This work computationally explores the vascular dynamics of nanoworms as drug carriers within blood flow by considering the effects of nanoworm length, stiffness, and local physiological conditions such as hematocrit. We found that nanoworms with length of 8 μm and moderate stiffness are the optimal choice as drug carriers for circulating within normal vascular network due to their lower near wall margination. Compared to those of spherical rigid particles, these nanoworms demonstrate significant demargination behaviors at hematocrit 20%, induced by the local hydrodynamic interactions. Specifically, the interactions between nanoworms and red blood cells create asymmetrical local flow fields, resulting in the demargination of nanoworms. In addition, the flexibility of nanoworms enables them to conform to the deformed shape of red blood cells under shear flow, leading to their high concentration within the core region of vessels. Therefore, the long blood circulation time of nanoworms can be partially attributed to their demargination behaviors and intertwinement with red blood cells. According to these simulation results, tuning the length and stiffness of nanoworms is the key to design drug carries with reduced near wall margination within normal vascular networks and extend their blood circulation time.

中文翻译：

---

纳米虫在血流中的异常血管动力学

纳米材料已被广泛用于药物输送平台的设计中。这项工作通过考虑纳米蠕虫长度，刚度和局部生理条件（如血细胞比容）的影响，以计算机方式探索了纳米蠕虫作为药物在血流中的血管动力学。我们发现长度为8μm且具有中等刚度的纳米蠕虫由于其近壁边缘较低而成为在正常血管网络中循环的药物载体的最佳选择。与球形刚性颗粒相比，这些纳米蠕虫在血细胞比容为20％时表现出明显的分界行为，这是由局部流体动力相互作用引起的。具体而言，纳米蠕虫与红细胞之间的相互作用会产生不对称的局部流场，从而导致纳米蠕虫的分界。此外，纳米蠕虫的柔韧性使它们能够在剪切流作用下适应红细胞的变形形状，从而使其在血管核心区域内高度集中。因此，纳米蠕虫的血液循环时间长可以部分归因于它们的分界行为和与红细胞的缠绕。根据这些模拟结果，调整纳米蠕虫的长度和刚度是设计载药减少正常血管网络内的近壁边缘并延长其血液循环时间的关键。纳米蠕虫的血液循环时间长，可以部分归因于它们的分界行为和与红细胞的缠绕。根据这些模拟结果，调整纳米蠕虫的长度和刚度是设计载药减少正常血管网络内的近壁边缘并延长其血液循环时间的关键。纳米蠕虫的血液循环时间长，可以部分归因于它们的分界行为和与红细胞的缠绕。根据这些模拟结果，调整纳米蠕虫的长度和刚度是设计载药减少正常血管网络内的近壁边缘并延长其血液循环时间的关键。