Simultaneous Fluorescent and Amperometric Detection Of Catecholamine Release From Neuroendocrine Cells With Transparent Diamond MEAs

Among all materials suitable for the fabrication of inert electrodes (Type-0) for amperometry, diamond is the one that shows the best pros/cons ratio. It is in fact very sensitive, chemically inert, biocompatible and transparent. This latter property was used so far only for cell inspection and not for optical measurements. In this work, we demonstrate for the first time the suitability of diamond MEAs for simultaneously detecting amperometric and fluorescence signals associated with calcium transients and catecholamine release in in vitro chromaffin cells. This is now possible thanks to the recently improved technology of the diamond MEAs, which allows to reach transmittance of ~ 50% in the whole optical range of interest, while keeping excellent amperometric sensitivity.