Abstract
In recent years, continuous achievements have been made on the research and development of the microchip for single-cell manipulation. Therefore, many methods for manipulations of bio-particles have been proposed, but most of proposed methods have some limitations and disadvantages. Hence the AC electrokinetic technologies have been developed and provided more effective for manipulations of bio-particles without harm. The term AC electrokinetics refers to the movement of particles using AC electric fields. An AC electric field induces a frequency-dependent dipole on a polarizable particle. The interaction between the dipole and the non-uniform electric field is such that the particle experiences a force. This effect is called dielectrophoresis (DEP) which is the common method for the manipulation of bio-particles. In this thesis we present a novel microfabricated dielectrophoretic trap designed to trap single cells. The design of our microchip consists of two mechanisms in order to reach the goal of single-cell trapping. First, cells accumulate on each microelectrode due to positive DEP force. Second, single cells are trapped individually in the region of minimum electric-field intensity due to negative DEP force. By utilizing the CFDRC simulation software, we validated the feasibility of the design concept. For the experiments, we used the latex bead and the HL-60 cell line as our trapped objects. The experiment results show that the trapping characteristic is dependent on frequency of the applied AC electric field and the properties of the trapped object. However the single-cell trapping has been demonstrated successfully through the experiments by tuning at the appropriate frequency of the applied AC electric field.