Uma B, Radhakrishnan R, Eckmann D M, Ayyaswamy P S
Department of Anesthesiology and Critical Care , University of Pennsylvania , Philadelphia, PA 19104 e-mail:
J Nanotechnol Eng Med. 2012 Aug;3(3):310101-310108. doi: 10.1115/1.4007522. Epub 2013 Jan 18.
A hybrid approach combining fluctuating hydrodynamics with generalized Langevin dynamics is employed to study the motion of a neutrally buoyant nanocarrier in an incompressible Newtonian stationary fluid medium. Both hydrodynamic interactions and adhesive interactions are included, as are different receptor-ligand bond constants relevant to medical applications. A direct numerical simulation adopting an arbitrary Lagrangian-Eulerian based finite element method is employed for the simulation. The flow around the particle and its motion are fully resolved. The temperatures of the particle associated with the various degrees of freedom satisfy the equipartition theorem. The potential of mean force (or free energy density) along a specified reaction coordinate for the harmonic (spring) interactions between the antibody and antigen is evaluated for two different bond constants. The numerical evaluations show excellent comparison with analytical results. This temporal multiscale modeling of hydrodynamic and microscopic interactions mediating nanocarrier motion and adhesion has important implications for designing nanocarriers for vascular targeted drug delivery.
采用一种将波动流体动力学与广义朗之万动力学相结合的混合方法，来研究中性浮力纳米载体在不可压缩牛顿静止流体介质中的运动。其中既考虑了流体动力学相互作用，也考虑了粘附相互作用，以及与医学应用相关的不同受体 - 配体键常数。模拟采用基于任意拉格朗日 - 欧拉的有限元方法进行直接数值模拟。颗粒周围的流动及其运动都得到了充分解析。与各种自由度相关的颗粒温度满足能量均分定理。针对两种不同的键常数，评估了抗体与抗原之间谐波（弹簧）相互作用沿指定反应坐标的平均力势（或自由能密度）。数值评估结果与解析结果具有出色的一致性。这种介导纳米载体运动和粘附的流体动力学与微观相互作用的时间多尺度建模，对于设计用于血管靶向药物递送的纳米载体具有重要意义。
