Can amphiphile architecture directly control vesicle size?

TL;DR

This paper demonstrates that by designing specific amphiphile architectures, it is possible to directly control vesicle size, overcoming the natural tendency of membranes to form planar structures, through coarse-grained modeling of tetrablock copolymers.

Contribution

The study introduces a molecular design approach to achieve vesicle size control by creating amphiphiles with preferred curvature, bypassing natural membrane relaxation mechanisms.

Findings

Designed tetrablock copolymers form membranes with specific curvature

Achieved low-polydispersity vesicles

Suppressed micellization through molecular design

Abstract

Bilayer membranes self-assembled from simple amphiphiles in solution always have a planar ground-state shape. This is a consequence of several internal relaxation mechanisms of the membrane and prevents the straightforward control of vesicle size. Here, we show that this principle can be circumvented and that direct size control by molecular design is a realistic possibility. Using coarse-grained calculations, we design tetrablock copolymers that form membranes with a preferred curvature, and demonstrate how to form low-polydispersity vesicles while suppressing micellization.