Fusion and fission pathways of vesicles from amphiphilic triblock copolymers: a dissipative particle dynamics simulation study

Abstract

Dissipative particle dynamics (DPD) simulations are employed to study the fusion and fission dynamics of polymeric vesicles formed from amphiphilic triblock copolymers. The amphiphilic molecule is built from two hydrophilic blocks and a hydrophobic middle block. Two different pathways for both fusion and fission processes of two-component vesicles with polymer-based symmetric membranes have been found in the simulations. For each of the pathways, the conditions required to obtain complete fusion and fission have been investigated. Moreover, the fission process of single-component vesicles with polymer-based asymmetric membranes has also been studied in the simulations. Interestingly, the daughter vesicles have the same composition as the parent vesicle and only one fission pathway has been observed. Furthermore, the fusion and fission pathways have been compared and distinct vesicle recycling pathways have been suggested according to the results from the simulations. These findings may be helpful in explaining the fusion and fission dynamics of vesicles and understanding the general principle of membranes.

Dissipative particle dynamic simulation study of lipid membrane

“…Even the subsequent "hemifusion-pore" transition which is initiated by trigger events have a small chance of happening for large vesicles. Recently, Liang's group explored the fusion and fission pathways of vesicles composed by complex architecture amphiphile A-B-A and A-B-C and found two pathways for both fusion and fission processes [40,41].…”

“…This reduction in the number of degrees of freedom yields a tremendous computational speedup. More recently, a mesoscopic simulation technique-disspative particle dynamic (DPD) simulation that can treat much larger system sizes and much longer time scales than full atomistic MD simulations have been applied to the study of vesicle formation, 2D-phase transition and vesicle fusion and fission [13,[39][40][41][42][43][44][45][46][47][48]. In such computer simulations, the molecules are allowed to move based only on the essential molecular properties and on the intermolecular interactions.…”

Self-assembly behavior of ABA coil-rod-coil triblock copolymers: A Brownian dynamics simulation approach

“…So far, most simulation work concerns ABA triblock copolymers containing coil blocks. [22][23][24][25][26][27] Studies of the phase behavior of ABA triblock copolymers having rigid blocks are limited. [28][29][30][31] AlSunaidi et al investigated liquid-crystalline ordering in coil-rod-coil triblock copolymers using the dissipative particle dynamics (DPD) method.…”

Coarse-grained modeling of vesicle responses to active rotational nanoparticles

“…The simulated value of bilayer thickness is ‫ݎ5‬ and the effective time scale of the simulation can be determined from the simulated lateral diffusion constants of the lipid bilayer. 24 The DPC bilayer thickness is about 4 nm with a diffusion coefficient around 5 ߤ݉ ଶ ‫ݏ‬ ିଵ . 25 …”