Biological Cell Identification by Integrating Micro-Fluidics, Electrical Impedance Spectroscopy and Stochastic Estimation

摘要

The integration of micro-fluidics, electrical impedance spectroscopy and stochastic estimation will lead to a device with enhanced detection capabilities. The goal of this thesis was to build a micro-fluidic electrical impedance measurement device that can be used in combination with a stochastic estimator to accurately identify living cells. A microdevice capable of making impedance measurements on individual living cells was designed and built using a series of standard microelectronic fabrication techniques. A microchannel was patterned in SU-8 photoresist between two gold microelectrodes on a two inch Pyrex 7740 wafer. The design process, the fabrication techniques for the microchannel, the fluid port fabrication and the cover slip bonding processes are described in detail. Small glass cover slips were bonded to the wafer using Loctite 3301 adhesive. Impedance measurements of single cells, in the microchannel device, were made using a HP4194A impedance analyzer. Preliminary analysis of the impedance data suggests that Jurkat cells have characteristic impedance signatures, corresponding to their cell type. The microdevice that was designed and built for this project should facilitate future work to implement a stochastic estimation algorithm capable of single cell identification.