Micro-Electric Impedance Tomography (m -EIT) is an electrophysiological technique under development to non-invasively measure the passive and active electrical properties of a single cell’s membrane with subcellular resolution. In this regard, m-EIT can reveal valuable information about cellular biophysics including fluctuations in integral membrane protein configuration. m EIT is different from conventional pipette-based electrophysiological tools in that it 1) provides dielectric information about the cell membrane using high frequencies of cellular interrogation 2) uses a noninvasive extracellular electrode array and 3) has the potential to simultaneously resolve the properties of several subcellular regions. In this study, Xenopus Oocytes were positioned within a planar, circumferentially distributed, electrode array. Radio waves (10kHz-10MHz) passed between electrode pairs were used to detect local changes in excitable cell membrane properties evoked by a membrane command potential. Results show that this approach can non-invasively measure local changes in membrane electrical properties in response to electrical excitation. Furthermore, preliminary results suggest that m -EIT has the potential to be used to visualize specific ion channel dynamics in living cell membranes.

Support: NIDCD R01 DC04928 and by National Science Foundation, IGERT

NSF DGE-9987616.