Galvanotactic and phototactic control of Tetrahymena pyriformis as a microfluidic workhorse

A eukaryotic ciliate, Tetrahymena pyriformis, has been controlled using galvanotaxis and phototaxis in a low Reynolds number fluidic environment. A cell-tracking algorithm demonstrates the controllability of Tetrahymena pyriformis under two types of external stimuli. Electrical stimulation, in the form of a direct current electric field through the containing fluid, causes a change in swimming direction toward the cathode. Photostimulation, by high intensity broadband light, results in a rotational motion of the cells. The motivation of this work is to progress further with biological microfluidic actuators and sensors for use in engineered systems.