Department of Physics and Materials Science, The University of Memphis, Memphis, TN 38152, USA.
Center for Nanophase Materials Sciences, Oak Ridge National Laboratory, Oak Ridge, TN 37831, USA.
Soft Matter. 2023 Feb 22;19(8):1499-1512. doi: 10.1039/d2sm01574a.
We present a numerical investigation of the modes of adhesion and endocytosis of two spherocylindrical nanoparticles (SCNPs) on planar and tensionless lipid membranes, using systematic molecular dynamics simulations of an implicit-solvent model, with varying values of the SCNPs' adhesion strength and dimensions. We found that at weak values of the adhesion energy per unit of area, , the SCNPs are monomeric and adhere to the membrane in the parallel mode. As is slightly increased, the SCNPs dimerize into wedged dimers, with an obtuse angle between their major axes that decreases with increasing . However, as is further increased, we found that the final adhesion state of the two SCNPs is strongly affected by the initial distance, , between their centers of mass, upon their adhesion. Namely, the SCNPs dimerize into wedged dimers, with an acute angle between their major axes, if is relatively small. However, for relatively high , they adhere individually to the membrane in the monomeric normal mode. For even higher values of and small values of , the SCNPs cluster into tubular dimers. However, they remain monomeric if is high. Finally, the SCNPs endocytose either as a tubular dimer, if is low or as monomers for large , with the onset value of of dimeric endocytosis being lower than that of monomeric endocytosis. Dimeric endocytosis requires that the SCNPs adhere simultaneously at nearby locations.
我们使用隐式溶剂模型的系统分子动力学模拟，针对两个球柱形纳米粒子（SCNP）在平面无张力脂质膜上的黏附与胞吞作用模式进行了数值研究，模拟中改变了 SCNP 的黏附强度和尺寸。我们发现，在单位面积黏附能较弱时，SCNP 呈单体状态并以平行模式黏附于膜上。当 稍有增加时，SCNP 二聚化为楔形二聚体，其长轴之间的钝角随 的增加而减小。然而，当 进一步增加时，我们发现两个 SCNP 的最终黏附状态强烈依赖于它们的质心之间的初始距离 。具体而言，如果 较小，则 SCNP 以锐角二聚化为楔形二聚体。然而，对于相对较高的 ，它们以单体正常模式单独黏附于膜上。对于甚至更高的 和较小的 ，SCNP 聚集成管状二聚体。但是，如果 较高，它们仍保持单体状态。最后，SCNP 以管状二聚体或单体的形式胞吞，如果 较低或 较大，则二聚体胞吞的起始值 低于单体胞吞。二聚体胞吞需要 SCNP 同时在附近位置黏附。
