Magnetically Actuated Heterogeneous Microcapsule-Robot for the Construction of 3D Bioartificial Architectures

Core-shell microcapsules as one type of the most attractive carriers and reactors have been widely applied in the fields of drug screening and tissue engineering owing to their excellent biocompatibility and semi-permeability. Yet, the spatial organization of microcapsules with specific shapes into three-dimensional (3D) ordered architectures still remains a big challenge. Here, we present a method to assemble shape-controllable core-shell microcapsules using an untethered magnetic microcapsule-robot. The microcapsule-robot with the shape-matching design can grab the building components tightly during the transportation and assembly processes. The core-shell feature of the microcapsule effectively prevents the magnetic nanoparticles from interacting with bioactive materials. The assembly results of cell-loaded heterogeneous microcapsules reveal that this strategy not only allows the magnetic microcapsule-robot to work in different workspaces in vitro for the creation of 3D constructions but also offers a noninvasive and dynamical manipulation platform by remotely controlling the position and orientation of the soft and liquid-like microcapsule components individually.