Applications in targeted gene or drug delivery call for nanobotic systems to navigate controllably towards target tissues and eventually enter specific cells. While chemical targeting enables tissue-specific delivery, magnetically propelled microrobots offer precise micrometer actuation and targeting which positions them as viable toolsfor future biomedical application.
We demonstrate actively propelled helical magnetic nanopropellers based on inorganic materials fabricated rapidly and in very large numbers (billions) using physical glancing angle deposition (GLAD). The propellers can be equipped with enzymatic and polymeric coatings to penetrate complex biological media [1-2] or transport material towards individual cells. Commonly used magnetic materials are either not biocompatible (Ni, Co) or possess weak magnetic moments (Fe, Fe3O4). We therefore examined FePt as a a fully biocompatible hard-magnetic material (in its L10 FePt phase). This is very promising for biomedical applications with magnetic micro- and nanodevices.