Cruz-Chu Eduardo R, Aksimentiev Aleksei, Schulten Klaus
Beckman Institute for Advanced Science and Technology, University of Illinois at Urbana-Champaign, Urbana, Illinois 61801, USA.
J Phys Chem B. 2006 Nov 2;110(43):21497-508. doi: 10.1021/jp063896o.
Amorphous silica is an inorganic material that is central for many nanotechnology applications, such as nanoelectronics, microfluidics, and nanopore sensors. To use molecular dynamics (MD) simulations to study the behavior of biomolecules interacting with silica, we developed a force field for amorphous silica surfaces based on their macroscopic wetting properties that is compatible with the CHARMM force field and TIP3P water model. The contact angle of a water droplet on a silica surface served as a criterion to tune the intermolecular interactions. The resulting force field was used to study the permeation of water through silica nanopores, illustrating the influence of the surface topography and the intermolecular parameters on permeation kinetics. We find that minute modeling of the amorphous surface is critical for MD studies, since the particular arrangement of surface atoms controls sensitively electrostatic interactions between silica and water.
无定形二氧化硅是一种无机材料，在许多纳米技术应用中至关重要，如纳米电子学、微流体学和纳米孔传感器。为了使用分子动力学（MD）模拟来研究生物分子与二氧化硅相互作用的行为，我们基于无定形二氧化硅表面的宏观润湿性开发了一种力场，该力场与CHARMM力场和TIP3P水模型兼容。水滴在二氧化硅表面的接触角作为调整分子间相互作用的标准。所得力场用于研究水通过二氧化硅纳米孔的渗透，阐明了表面形貌和分子间参数对渗透动力学的影响。我们发现，无定形表面的精细建模对于MD研究至关重要，因为表面原子的特定排列敏感地控制着二氧化硅与水之间的静电相互作用。
