The long-term effect of chronically
implanted electrodes is the formation of a
glial scar. Therefore, it is imperative to assess the biocompatibility of materials before employing them in neural
electrode fabrication.
Platinum alloy and
iridium oxide have been identified as good candidates as neural
electrode biomaterials due to their mechanical and electrical properties, however, effect of
glial scar formation for these two materials is lacking. In this study, we applied a glial
scarring assay to observe the cellular reactivity to
platinum alloy and
iridium oxide wires in order to assess the biocompatibility based on previously defined characteristics. Through real-time PCR, immunostaining and imaging techniques, we will advance the understanding of the biocompatibility of these materials. Results of this study demonstrate
iridium oxide wires exhibited a more significant reactive response as compared to
platinum alloy wires. Cells cultured with
platinum alloy wires had less GFAP gene expression, lower average GFAP intensity, and smaller
glial scar thickness. Collectively, these results indicated that
platinum alloy wires were more biocompatible than the
iridium oxide wires.