Experimental System Construction And Dielectrophoretic Force Field Calculation Model Of Cell Electrorotation Chip

Since the mid-90s, biochip technology is one of the most far-reaching strides in science and technology. Biochip is an interdisciplinary which integrated the financial microelectronics, biology, physics, chemistry, and computer science. Biochip has great value in basic research and significant industrial prospects. The dielectrophoresis chip (Dielectrophoresis Chip, DEP Chip) technology is one of the important bio-chip technologies. This technology has many advantages, such as without injury, fastly, and easily be integrated in micro-system. It becomes the mainly method to operate the bio-fluid in the micro-system within the life sciences, analysis chemistry and many other areas. With a deep understanding of this technology, many type micro-system components were studied. Among them, the electroration chip has been already widely applied on many areas including the measurement of the cell activity, the cell conductance and cell membrane capacitance. This chip measured these parameters using the spectrum of the biological particles in the chip.The work in this paper mainly including solving analytical solution of the electric field distribution in the electroration chip using SCM method; analsising the measurement error of each area by the distribution of the dielectrophoretic force field in electroration chip; studying the reason and the effects of the biological particles'moving during the measurement; design the dielectrophoresis chip with the new universal equation which derived in this paper. In theory, the paper first solved analytical solution of the electric field distribution with different phase of the potential using the SCM method and the electric field superposition theorem. And the reason of the biological particles'moving were analyzed by the distribution of the dielectrophoretic force field solved. Based on the above, the main reason we found was that two dielectrophoretic force traps change their position with the potential phase changing.The measurement errors within different areas were analysed by the distribution of the dielectrophoretic force field and the electic field in this paper. An area was defined base on the analysis of the measurement errors in wich the measurement on the biological particles has negligible error. This area can be defined as a circle area which the center is the origin point and the radius is 36% of the radius of the electrode. The maxium error in this area is less than 5%. Considering the biological particles' moving, this area is redefined as a circle area which radius is just 30% of the radius of the electrode. The fluctuations of the dielectrophoretic force at any position in this area are less than 25%. Related experiments described in this paper validated the theory above.The SCM method given in this paper has many advantages, such as calculation rapidly, accurate result and using less computation resource. Combined with image processing technology, the SCM method is a best method to real-time compute and correct the measurement result. The detail of relevant method and algorithm is described below in this paper.A new method to design the dielectrophoretic electrode was described in this paper. This method is based on the universal equation which is derived from Laplace equation. This universal equation raised the awareness of dielectrophoresis, changed the common design methods which mainly based on experience. For the universal equation, In this paper, two methods were metioned to solve the universal equation. The one is analytical method, and the other is the difference method.