Diamond is the only transparent semiconductor electrode material used in heavy duty electrochemistry and therefore also an attractive material for microelectrode arrays in biochemistry. Three configurations are described: (1) single crystalline diamond (SCD), with a substrate size of less than 4mm x 4mm, serving as ideal reference material, (2) nanodiamond (NCD) thin films on silicon substrates, representing an application of the commonly used diamond MEMS technology and (3) NCD thin films on sapphire, sapphire being the standard substrate for GaN optoelectronics and electronics. A basic electrode array (quadropole MEA) has been developed for this investigation. For optimized deposition conditions, the influence of grain boundaries could be widely suppressed and comparable electrode characteristics could be obtained for all cases. In the diamond-on-Si case, fragile membranes need to be etched for optical transparency. Full advantage of the diamond electrode properties combined with the biological requirements is therefore only obtained by the diamond-on-sapphire system. Preliminary results of the amperometric detection of secretory cells activity are presented including a first comparison with discrete carbon fiber electrodes.
Diamond microelectrodes for amperometric detection of secretory cells activity
CARABELLI, Valentina;MARCANTONI, Andrea;CARBONE, Emilio
2009-01-01
Abstract
Diamond is the only transparent semiconductor electrode material used in heavy duty electrochemistry and therefore also an attractive material for microelectrode arrays in biochemistry. Three configurations are described: (1) single crystalline diamond (SCD), with a substrate size of less than 4mm x 4mm, serving as ideal reference material, (2) nanodiamond (NCD) thin films on silicon substrates, representing an application of the commonly used diamond MEMS technology and (3) NCD thin films on sapphire, sapphire being the standard substrate for GaN optoelectronics and electronics. A basic electrode array (quadropole MEA) has been developed for this investigation. For optimized deposition conditions, the influence of grain boundaries could be widely suppressed and comparable electrode characteristics could be obtained for all cases. In the diamond-on-Si case, fragile membranes need to be etched for optical transparency. Full advantage of the diamond electrode properties combined with the biological requirements is therefore only obtained by the diamond-on-sapphire system. Preliminary results of the amperometric detection of secretory cells activity are presented including a first comparison with discrete carbon fiber electrodes.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.