In vivo electrochemical impedance measurement on single cell membrane

The electrochemical characteristics of the plasma membranes of single cells and organelles were investigated. Silicon fabrication technology was used to produce a metal ultra-microelectrode (UME). Furthermore, the UME was characterized in a cell medium using electrochemical impedance spectroscopy (EIS). A single rat fibroblast cell, or chloroplast purified from Peperomia metallica leaves, was immobilized by a micropipette after which the UME was inserted into its cytosolic space through cell membrane using a piezo actuator. An in vivo EIS measurement between the UME and the counter electrode outside of a single cell was taken. The measurements were analyzed using equivalent circuits in order to estimate the membrane impedance of a single cell. (C) 2011 Elsevier B.V. All rights reserved.