Date of Award

December 2020

Document Type


Degree Name

Master of Science (MS)


Mechanical Engineering

Committee Member

Rodrigo Martinez-Duatre

Committee Member

Xianchung Xuan

Committee Member

Phanindra Tallapragada


Dielectrophoresis (DEP) is an established technique used as a label-free method to manipulate microorganisms by exploiting the interaction of targeted microorganisms with a non-uniform electric field. The strength and direction of the DEP force on a targeted cell, specifically Komagataeibacter xylinus (K. xylinus), is dependent on the frequency of the applied electric field as well as the dielectric properties of the bacterial cell and suspending media.

K. xylinus is a microorganism that can synthesize a fibrous, web-shaped organic material called bacterial cellulose (BC), which contains desirable properties such as high mechanical strength and increased water holding capabilities. By combining DEP techniques with this BC synthesizing microorganism, this creates the potential for controlled and enhanced growth allowing BC to be tailored to specific properties at specific locations. However, literature has reported limited information regarding the use of DEP techniques to study how electric fields affect BC synthesis in a microfluidic reactor.

In this study, a titanium-based semicircular microelectrode chip was used to study how electrostimulation can potentially manipulate and influence the synthesis of BC at unique regions of interest where the electric field is greatest. This study features experiments running over fourteen days with an AC induced electric field at polarization voltages of 1 Vpp, 2 Vpp, and 5 Vpp at a frequency of 750 kHz. Results suggest that BC synthesis is possible and can be manipulated over an extended period as the polarization voltage increased where the electric field is greatest.



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