Metachronal motion of artificial cilia using induced charge electro-osmosis

The wave-like metachronal motion of natural and artificial cilia is important to obtain a net flow in a low Reynolds number regime. In this study, we report that artificial cilia consisting of three beams with three different lengths arranged in parallel in order of length show the metachronal motion through induced charge electro-osmosis (ICEO) by the suddenly applied AC electric fields, because of the different response times due to the different beam lengths. Furthermore, we found that the three beams of the ICEO cilia recover at the almost same time when we suddenly turned off AC electric fields. These behaviors are discussed based on a mathematical model. Our findings are useful for designing ICEO cilia, and should contribute to the development of innovative microfluidic applications in the future.