Magnetic small-scale robots: Principles, applications and challenges

Abstract

Last two decades has seen a growth of the research on untethered mobile small-scale robots. These motile devices display the ability to travel through fluids by transforming the energy generated by an external power source into mechanical motion. As a result, these devices are being recognized as promising platforms to break through the drawbacks of nanoparticle drug delivery systems. Among the family of small-scale devices, magnetic micro- and nanorobots, which refer to those devices wirelessly controlled by external magnetic fields, are arguably the most appealing systems for biomedical applications. Magnetic fields display biocompatibility characteristics in a wide range of conditions, and they can penetrate body tissues with minimal interaction. Additionally, magnetic fields can be generated in several forms (rotating, oscillating, gradients), enabling a rich collection of motion mechanisms, including several that mimic those of cells and microorganisms. In the present talk, we will introduce magnetic small-scale robots, their actuation principles, designs and constituent materials. Next, we will discuss about existing and potential applications in the biomedical area. Finally, we will conclude with remaining challenges for their translation into clinical applications, with a special focus in the area of intravascular drug delivery.