Two novel methods of measuring bacterial motor characteristics using ac field effects in a microfabricated electrode system are presented in this paper. One is the measurement of the external force-to-velocity (F-v) characteristics of swimming bacteria. Electrostatic orientation of bacteria parallel to the field lines is used to guide the bacterial locomotion along a line. Then dielectrophoresis is used to apply an external force either forward or backward to the swimming bacteria, and by measuring the velocity of locomotion, the F-v curve is obtained. The other is the measurement of torque-to-speed (T-ω) characteristics of the motor. Electrorotation is used to apply external torque to the tethered cells, and by changing the applied torque and measuring the rotation speed, the T-w curves obtained. The results show that the motor generates approximately constant torque in the measured range of ω (0–100 Hz), regardless of the direction of rotation.
ASJC Scopus subject areas
- Control and Systems Engineering
- Industrial and Manufacturing Engineering
- Electrical and Electronic Engineering