Electrokinetic system to determine differences of electrorotation and traveling-wave electrophoresis between autotrophic and heterotrophic algal cells

Electrorotation and traveling-wave dielectrophoresis are non-invasive methods and can be used to determine the dielectric properties of particles. In the present study, we have developed an electrokinetic system using microfabricated electrorotation and traveling-wave dielectrophoresis electrodes to determine the dielectric differences of algal cells. Chlorella protothecoides is a microalgae that can be photoautotrophically or heterotrophically grown under different culture conditions. Different culture conditions resulted in biochemical differences between autotrophic and heterotrophic cells of C. protothecoides, and therefore, distinctions of dielectric properties. We presented differences in their electrorotational responses, which were also confirmed by traveling-wave dielectrophoresis. Based on these electrical and biochemical effects. It was suggested that electrorotation and traveling-wave dielectrophoresis responses could be used to reflect the biochemical differences of biological particles including algal cells.