Anti-fouling surfaces: removal of micro-particles by magnetic artificial cilia

Biological cilia are hair-like structures lining many biological surfaces. There are many examples in nature in which oscillating cilia efficiently manipulate particles in their vicinity, e.g. for feeding, anti-fouling or cell transport. In this paper, we experimentally demonstrate that surfaces covered with artificial cilia have the capacity to remove micro-particles from the ciliated area, creating a particle-free area. The artificial cilia used are micro-moulded magnetic artificial cilia (MAC), actuated externally by a homebuilt magnetic setup. The ciliated surface is capable of removing a large size range of particles except for particles which have a diameter that is similar to the cilia pitch. It is also able to remove irregular-shaped sand particles in both water and air. These findings can contribute to the development of novel particle manipulation and self-cleaning/ antifouling surfaces, which can find application in, for example, lab-on-a-chip devices and marine antifouling.