Microelectrodes

Chemical and Morphological Changes on Platinum Microelectrode Surfaces Subjected to a Dielectrophoretic Field

Researcher

Aytug Gencoglu

Description and Motivation

Platinum is a relatively inert material, and it is often taken for granted that the properties of platinum microelectrodes stay constant during microdevice experiments. However, a former member of our laboratory observed that used platinum microelectrodes disrupt red blood cells (in an AC electric field) better than new ones [1]. This research aims to reveal the nature of the chemical and morphological changes causing this change in performance and the extent to which these changes occur. Variability in performance of platinum microelectrodes could have a serious impact on the operation of microdevices, where they are utilized, eletrode lifetime and field consistency, among other things. To understand the chemical changes, we have been using techniques such as X-ray photoelectron spectroscopy (XPS) and cyclic voltammetry (CV). We have been employing scanning electron microscopy (SEM) to investigate morphological changes. Our results so far suggest the oxidation of platinum and reaction of platinum take place readily when platinum microelectrodes are in AC electric fields [2]. This research is fundamental in nature and will generate important background knowledge that will help other researchers across the globe develop robust microdevices.

Resources

• Walton, M., “MicroMadness and Me: Erythrocyte Rupturing Responses in Dielectrophoretic MicroDevices.” A Research Experience for Undergraduates at Mississippi State University.
• Gencoglu, A., Cotten, E. F., Pullen, S. A., Thompson, S., Tosun, B. S., and Minerick, A. R., “Chemical and Morphological Changes on Platinum Microelectrode Surfaces Subjected to a Dielectrophoretic Field.” Graduate Research Seminar for Gordon Research Conference on Analytical Biosensors; June 2008.

Personal Motivation