水溶液中管状带电纳米颗粒跨膜输运的分子动力学模拟  

MOLECULAR DYNAMICS SIMULATION OF THE TRANSPORT OF CHARGED TUBE-LIKE NANOPARTICLES THROUGH A FLUIDIC CHANNEL

作　　者：郝亮[1] 苏加叶[1] 郭洪霞[1] 

机构地区：[1]中国科学院化学研究所高分子物理与化学国家重点实验室,北京100190

出　　处：《高分子学报》2013年第12期1561-1566,共6页Acta Polymerica Sinica

基　　金：国家自然科学基金(基金号21204093;21174154;20874110)资助项目

摘　　要：采用分子动力学模拟方法研究了水溶液中管状带电纳米颗粒的跨膜输运过程.主要考察了纳米颗粒的尺寸、所带的电性以及外驱动电场的大小对输运动力学行为的影响.研究表明,随着外电场的增大,所有管状纳米颗粒的跨膜流量都迅速增大,其中有些颗粒呈现出非单调的变化,这与之前发现的球形纳米颗粒单调增加的趋势截然不同;而跨膜时间会随电场强度的增大而单调减小,并符合幂指数衰减的规律,这与郎之万动力学的理论预测一致.在同一电场强度下,管状颗粒的跨膜流量要比球形颗粒小几倍到一个数量级,而跨膜时间则大几倍.与球形颗粒相比,管状颗粒需要牺牲一定的旋转自由度才能进入通道,因此它们通常具有低的跨膜流量和长的跨膜时间.研究结果加深了人们对于不同形状纳米颗粒跨膜输运的理解,对高效纳米载体的设计具有一定的参考意义.Molecular dynamics simulation is used to study the transport of charged tube-like nanoparticles（ NPs） through a fluidic channel. Herein,the effect of NP size,charge nature and external electric field（ E） on the transport dynamics is considered. With the increase of E,the NP flux increases remarkably,where some of them exhibit nonmonotonous variations that are different from the flux behaviors of spherical NPs. The translocation time yields to a power law decrease with E,which is in agreement with the prediction of Langevin dynamics. Under a given E,the flux of tube-like NPs is several times and even an order smaller than that of spherical NPs,and inversely the translocation time is several times larger. Compared to spherical NPs,the tubelike NPs should always sacrifice some rotational freedom to enter the channel,thus they have smaller flux and longer translocation time. These results enrich the understanding of the NP shape effect,which has implications in the design of high efficient nanocarriers.

关 键 词：纳米颗粒 水 输运 膜 分子动力学 

分 类 号：TB383.1[一般工业技术—材料科学与工程]