Microcapsules from the Self-Assembly of Nanoparticles at Interfaces

Microcapsules are multifunctional materials with applications in various,fields related to biomedical research. In the previous studies, lipids and polymers are used as microcapsule shell construction materials. Recently, the self-assembly of nanoparticles at emulsion interfaces have showed great potential as an alternative for microcapsule fabrication. The construction of microcapsule shells using nanoparticles as building blocks incorporated the unique physicochemical properties of nanoparticles into the functional capabilities of the microcapsules. The new properties derived from nanoparticles, such as enhanced mechanical strength, controllable permeability, readily surface modification and controlled release, making the microcapsules of great interest in bio-delivery applications. In this paper, the recent scientific advances in the self-assembly of nanoparticle protected microcapsules including the theories for nanoparticle interfacial assembly, the strategies for the fabrication of stable microcapsule shells, and the reduction of polydispersity of microcapsules are reviewed. The challenges for the self-assembly of nano-sized capsules are discussed and a proposal for the development of nano-sized capsules is concluded.