Nano Express

Nanoscale Research Letters

, Volume 5, Issue 2, pp 296-301

Open Access This content is freely available online to anyone, anywhere at any time.

Biomolecular Nano-Flow-Sensor to Measure Near-Surface Flow

  • Sang-Wook LeeAffiliated withInstitute of Industrial Science, University of Tokyo
  • , Haruyuki KinoshitaAffiliated withInstitute of Industrial Science, University of Tokyo
  • , Hiroyuki NojiAffiliated withThe Institute of Science and Industrial Research, Osaka University
  • , Teruo FujiiAffiliated withInstitute of Industrial Science, University of Tokyo
  • , Takatoki YamamotoAffiliated withDepartment of Mechanical and Control Engineering, Tokyo Institute of Technology Email author 


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.


Microfluidics Near-surface F1-ATPase Micro-PIV Flow-sensor