Colloidosomes: Selectively Permeable Capsules Composed of Colloidal Particles

TLDR

The study presents a method to fabricate solid capsules with precise control over size, permeability, mechanical strength, and compatibility. The capsules are fabricated by self‑assembling colloidal particles onto emulsion droplet interfaces, locking them into elastic shells, and then transferring the droplets into a fresh continuous phase identical to the interior. The resultant colloidosomes are hollow, elastic shells with tunable permeability and elasticity; their generality and robustness are demonstrated across various solvents, particles, and contents, indicating potential for cellular immunoisolation.

Abstract

We present an approach to fabricate solid capsules with precise control of size, permeability, mechanical strength, and compatibility. The capsules are fabricated by the self-assembly of colloidal particles onto the interface of emulsion droplets. After the particles are locked together to form elastic shells, the emulsion droplets are transferred to a fresh continuous-phase fluid that is the same as that inside the droplets. The resultant structures, which we call "colloidosomes," are hollow, elastic shells whose permeability and elasticity can be precisely controlled. The generality and robustness of these structures and their potential for cellular immunoisolation are demonstrated by the use of a variety of solvents, particles, and contents.