title: Biomolecular nano-flow-sensor to measure near-surface flow.
abstract: We have proposed and experimentally demonstrated that the measurement of the near-surface flow at the interface between a liquid and solid using a 10 nm-sized biomolecular motor of F1-ATPase as a nano-flow-sensor. For this purpose, we developed a microfluidic test-bed chip to precisely control the liquid flow acting on the F1-ATPase. In order to visualize the rotation of F1-ATPase, several hundreds nanometer-sized particle was immobilized at the rotational axis of F1-ATPase to enhance the rotation to be detected by optical microscopy. The rotational motion of F1-ATPase, which was immobilized on an inner surface of the test-bed chip, was measured to obtain the correlation between the near-surface flow and the rotation speed of F1-ATPase. As a result, we obtained the relationship that the rotation speed of F1-ATPase was linearly decelerated with increasing flow velocity. The mechanism of the correlation between the rotation speed and the near-surface flow remains unclear, however the concept to use biomolecule as a nano-flow-sensor was proofed successfully.(See supplementary material 1).
authors.affiliation: Department of Mechanical and Control Engineering, Tokyo Institute of Technology, Ishikawadai 1-314, Ookayama 2-12-1 Meguro-ku, Tokyo, 152-8550, Japan. yamamoto@mes.titech.ac.jp.
authors.forename: Sang-Wook
authors.initials: SW
authors.lastname: Lee
authors.forename: Haruyuki
authors.initials: H
authors.lastname: Kinoshita
authors.forename: Hiroyuki
authors.initials: H
authors.lastname: Noji
authors.forename: Teruo
authors.initials: T
authors.lastname: Fujii
authors.forename: Takatoki
authors.initials: T
authors.lastname: Yamamoto