Department of Biomedical Engineering and Department of Physics and Materials Science, The University of Memphis, Memphis, TN 38152, USA.
Soft Matter. 2021 Jan 28;17(4):1016-1027. doi: 10.1039/d0sm01642j. Epub 2020 Dec 7.
Using molecular dynamics simulations of a coarse-grained implicit solvent model, we investigate the binding of crescent-shaped nanoparticles (NPs) on tubular lipid membranes. The NPs adhere to the membrane through their concave side. We found that the binding/unbinding transition is first-order, with the threshold binding energy being higher than the unbinding threshold, and the energy barrier between the bound and unbound states at the transition that increases with increasing the NP's arclength L or curvature mismatch μ = R/R, where R and R are the radii of curvature of the tubular membrane and the NP, respectively. Furthermore, we found that the threshold binding energy increases with increasing either L or μ. NPs with curvature larger than that of the tubule (μ > 1) lie perpendicularly to the tubule's axis. However, for μ smaller than a specific arclength-dependent mismatch μ*, the NPs are tilted with respect to the tubule's axis, with the tilt angle that increases with decreasing μ. We also investigated the self-assembly of the NPs on the tubule at relatively weak adhesion strength and found that for μ > 1 and high values of L, the NPs self-assemble into linear chains, and lie side-by-side. For μ < μ* and high L, the NPs also self-assemble into chains, while being tilted with respect to the tubule's axis.
利用粗粒化隐式溶剂模型的分子动力学模拟，我们研究了新月形纳米粒子（NPs）在管状脂质膜上的结合。NPs 通过其凹面附着在膜上。我们发现结合/解吸转变是一级的，其阈值结合能高于解吸阈值，并且在转变过程中，结合态和非结合态之间的能量势垒随着 NP 的弧长 L 或曲率失配 μ=R/R 的增加而增加，其中 R 和 R 分别是管状膜和 NP 的曲率半径。此外，我们发现阈值结合能随着 L 或 μ 的增加而增加。曲率大于管状（μ>1）的 NPs 垂直于管状的轴。然而，对于 μ 小于特定的弧长相关失配 μ*，相对于管状的轴， NPs 会倾斜，且倾斜角度随着 μ 的减小而增加。我们还研究了在相对较弱的粘附强度下 NPs 在管状上的自组装，发现对于 μ>1 和高 L 值，NPs 自组装成线性链，并且彼此并排排列。对于 μ<μ*和高 L，NPs 也会自组装成链，同时相对于管状的轴倾斜。
