Soft-hard magnetically driven microrobotic devices

Abstract

Magnetic micro- and nanorobots are promising candidates for the delivery of therapeutic agents in difficult-to-reach locations of the human body. These devices can swim through fluids by means of external magnetic fields. Depending on the specific design, these devices can exhibit a plethora of motion patterns as a function of the applied magnetic field. Many of these devices can also mimic the motion strategies of small organisms and cells. The vast majority of magnetic micro – and nanorobots are constructed either with magnetic hard blocks, or soft magnetic polymer nanocomposites. The first type usually comprises materials with poor biocompatibility characteristics (except for fully iron devices and few iron alloys), limited motion versatility and mechanical features far from those of biological tissues. The second, while being more versatile and adaptable in terms of motion and shape, and more similar to tissues in terms of their mechanical properties, are limited in terms of magnetic force. To overcome these limitations, devices that marry the excellent magnetic performance of magnetic hard components with the advantageous properties of soft polymeric materials for biomedicine should be developed. In this talk, we will showcase a strategy to produce microrobotic devices that comprise interlocked metallic and polymeric parts. The devices are constructed by means of template-assisted 3D printing by combining electrodeposition and mold-casting. We will demonstrate the richness of these devices in terms of motion. Finally, we will mention the potential applications of these machines for intravascular applications.