Department of Physics and Materials Science, The University of Memphis, Memphis, Tennessee 38152, USA.
J Chem Phys. 2022 Jun 21;156(23):234901. doi: 10.1063/5.0094234.
The adhesion modes and endocytosis pathway of spherocylindrical nanoparticles (NPs) are investigated numerically using molecular dynamics simulations of a coarse-grained implicit-solvent model. The investigation is performed systematically with respect to the adhesion energy density ξ, NP's diameter D, and NP's aspect ratio α. At weak ξ, the NP adheres to the membrane through a parallel mode, i.e., its principal axis is parallel to the membrane. However, for relatively large ξ, the NP adheres through a perpendicular mode, i.e., the NP is invaginated, such as its principal axis is nearly perpendicular to the membrane. The value of ξ at the transition from the parallel to the perpendicular mode decreases with increasing the D or α, in agreement with theoretical arguments based on the Helfrich Hamiltonian. As ξ is further increased, the NP undergoes endocytosis, with the value of ξ at the endocytosis threshold that is independent of the aspect ratio but decreases with increasing D. The kinetics of endocytosis depends strongly on ξ and D. While for low values of D, the NP first rotates to a parallel orientation then to a perpendicular orientation. At high values of ξ or D, the NP is endocytosed while in the parallel orientation.
使用粗粒化隐式溶剂模型的分子动力学模拟，数值研究了球形-圆柱形纳米粒子（NPs）的粘附模式和内吞作用途径。系统地研究了粘附能量密度ξ、NP 的直径 D 和 NP 的纵横比α。在较弱的ξ时，NP 通过平行模式附着在膜上，即其主轴与膜平行。然而，对于相对较大的 ξ，NP 通过垂直模式附着，即 NP 被内陷，例如其主轴几乎垂直于膜。平行模式到垂直模式的转变时的 ξ 值随着 D 或 α 的增加而减小，这与基于 Helfrich 哈密顿量的理论论点一致。随着 ξ 的进一步增加，NP 经历内吞作用，内吞作用的阈值与纵横比无关，但随着 D 的增加而减小。内吞作用的动力学强烈依赖于 ξ 和 D。对于 D 值较低的情况，NP 首先旋转到平行取向，然后旋转到垂直取向。在 ξ 或 D 值较高的情况下，NP 在平行取向时被内吞。
