Impedance Tomography Microchip for the Analysis of Biological Cell
Kevin T. C. Chai

The introduction of electrochemical applications into biomedical field has paved way for the integration of electronics with biology. Furthermore, the emergence of nanotechnology and its capabilities in making very precise measurements have further enhance the process of integration. This research will attempt to incorporate the precision achievable through nanotechnology into creating an electrical impedance tomography (EIT) on a biological cell. The understanding on basic cell biology is essential for the creation of the EIT system. The basis of this EIT system is built upon the structural characteristics of the biological cell. These structural characteristics are the essence and its electrical behaviour that enables it to thrive in a suitable artificial environment. EIT is a technique for mapping the distribution of electrical conductivity (real or complex) within a cell. The conductivity of the cell will be deduced from the measurement of voltages or currents on the surface of the cell as a result of non-invasively applied electrical stimulus. The impedance measurement on the cell will be done with a microchip that is fabricated using conventional CMOS process.

The microchip is made up of an array of microelectrode and peripheral circuitry that controls the functionality of the microchip. These microelectrodes will facilitate the transmission of the electrical signal and the impedance measurement. A phase detector system employing the vector network analysis method will be used to decipher the impedance data collected from the microchip.

Finally, the reconstruction algorithm programmed with MATLAB will be used to reconstruct the impedance image by interpolating the data collected through the phase detector system. Apart from interpolating the impedance data, there are also other factors that are essential to the creation of this EIT system. Factors such the microelectrode design and the procedures for preparing the microchip for interaction with the cell are also essential for the construction of the EIT system.

The microchip is made up of an array of microelectrode and peripheral circuitry that controls the functionality of the microchip. These microelectrodes will facilitate the transmission of the electrical signal and the impedance measurement. A phase detector system employing the vector network analysis method will be used to decipher the impedance data collected from the microchip. Finally, the reconstruction algorithm programmed with MATLAB will be used to reconstruct the impedance image by interpolating the data collected through the phase detector system. Apart from interpolating the impedance data, there are also other factors that are essential to the creation of this EIT system. Factors such the microelectrode design and the procedures for preparing the microchip for interaction with the cell are also essential for the construction of the EIT system.