Magnetic Micromotors for Resilient and Reversible Cargo Transport in and between Microfluidic Environments

In this work we present magnetically propelled micromotors that can capture, transport, and release microscopic cargo in a resilient and reversible manner. In a proof-of-concept experiment, we demonstrate the transfer of a cargo-loaded micromotor between separate microfluidic environments by pipetting for potential chip-to-chip or chip-to-body transfer. This step is important for many biomedical applications of motile microdevices where not everything from preparation to application can happen in a single on-chip environment. A simple propulsion and cargo capture mechanism based solely on rotation allows the presented micromotors to deliver microparticles in high-viscosity medium and confined microchannels without any external trigger except for a rotating magnetic field, employing biocompatible materials only, toward biomedical applications.