Optically transparent microelectrode arrays for electrochemical and electrophysiological measurements or stimulation

A microelectrode array device for biological imaging comprising:

• a well for containing a liquid medium;
• an optically transparent substrate;
• a microelectrode array comprising:
• multiple electrode pads, each comprising a conductive film having a thickness between 5 nm and 1000 nm, the conductive film comprising one or both of a carbon nanotube network and graphene;
• at least one counter electrode;
• electrically conductive traces connecting the electrode pads with a voltage source and connecting the at least one counter electrode with the voltage source such that a potential difference can be provided between the electrode pads and the counter electrode.

A cellular imaging method comprising:

• providing a microelectrode array device with:
• a well for containing a liquid medium;
• an optically transparent substrate;
• and
• a microelectrode array comprising:
• multiple electrode pads, each comprising a conductive film having a thickness between 5 nm and 1000 nm, the conductive film comprising one or both of a carbon nanotube network and graphene;
• at least one counter electrode;
• electrically conductive traces connecting the electrode pads with a voltage source and connecting the at least one counter electrode with the voltage source such that a potential difference can be provided between the electrode pads and the counter electrode;
• depositing cells or tissue on the microelectrode array within the well;
• measuring one or both of the voltage and current from each of the electrode pads;
• and
• imaging the cells or tissue using one or both of an optical and fluorescence microscope.