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Chemo-Sensitive Running Droplet

Yutaka Sumino·Masaharu Nagayama·Hiroyuki Kitahata·Shin-ichiro M. Nomura·Nobuyuki Magome·Yoshihito Mori·Kenichi Yoshikawa
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Abstract

Chemical control of the spontaneous motion of a reactive oil droplet moving on a glass substrate under an aqueous phase is reported. Experimental results show that the self-motion of an oil droplet is confined on an acid-treated glass surface. The transient behavior of oil-droplet motion is also observed with a high-speed video camera. A mathematical model that incorporates the effect of the glass surface charge is built based on the experimental observation of oil-droplet motion. A numerical simulation of this mathematical model reproduced the essential features concerning confinement within a certain chemical territory of oil-droplet motion, and also its transient behavior. Our results may shed light on physical aspects of reactive spreading and a chemotaxis in living things.

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Yutaka Sumino, Masaharu Nagayama, Hiroyuki Kitahata, Shin-ichiro M. Nomura, Nobuyuki Magome, Yoshihito Mori, Kenichi Yoshikawa. 2005-08-23. Chemo-Sensitive Running Droplet. https://doi.org/10.1103/physreve.72.041603

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