Multichannel Systems MEA Manual - Manual (Page 16)

MEA Manual
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4.4 Hexa MEA: 60HexaMEA
60HexaMEA-Ti, 60HexaMEA-ITO, 60HexaMEA40/10iR-ITO
Electrode layout for 60HexaMEA-Ti and 60HexaMEA-ITO.
Electrode layout for 60HexaMEA40/10iR-ITO.
HexaMEAs feature a hexagonal layout, perfect for recording from retina.
The 60 electrodes of 60HexaMEA-Ti or 60HexaMEA-ITO are aligned in a special configuration with varying
electrode diameters (10, 20, 30 μm) and interelectrode distances (see upper pictures).The specific layout
resembles ideally the regularity of the retina's architecture. The density of neurons is more important in the
center than in the peripheral. This is matched by the density of electrodes on the MEA, which is also higher
in the center than in the peripheral.
The flat, round electrodes are made of titanium nitride (TiN).
Tracks are made of opaque Ti or transparent ITO, and contact pads are made of TiN or ITO.
The insulation material is silicon nitride.
Electrodes in the center have a diameter of 10 μm with an interelectrode distance of 20 μm, where
the peripheral electrodes have a diameter of 20 μm and 30 μm. This type of HexaMEA (60HexaMEA-Ti,
60HexaMEA-ITO ) provides no internal reference electrode.
The electrodes of 60HexaMEA40/10iR-ITO are configured with invariable interelectrode distance of 40 μm,
and with TiN electrodes of 10 μm diameter. They include a big internal reference electrode. The tracks and
contact pads are made of ITO.
Using 60HexaMEAs
The same material is used for standard MEAs and HexaMEAs. Therefore, they are equally robust and heat-
stabilized. They can be autoclaved and coated with different procedures for cell and tissue cultures.