Fig 5.

In vitro neuronal recording and stimulation of cortical networks using RuOx microelectrodes. (a) DIV21 murine-derived cortical networks cultured on MEA substrates with RuOx (top), IrOx (middle), and ITO (bottom) electrode sites on a single array. (b) Representative raw traces of filtered continuous data on DIV21 from RuOx (top), IrOx (middle), and ITO (bottom) electrodes demonstrate detection of well-resolved extracellular action potentials from neuronal cells. (c) Mean extracellular waveforms consistent with time and shape of extracellular action potentials recorded from single representative RuOx (top, blue and green waveforms represent two distinct units as identified in PC space) and IrOx (bottom, blue and red waveforms represent two distinct units as identified in PC space) electrode sites. (D) Representative raw trace of evoked bursting activity in response to a biphasic current stimulus (cathodic leading edge, 200 μs pulse width, 20 stimuli at 1 Hz frequency) applied through a RuOx microelectrode. Red arrow indicates the beginning of the current stimulus and inset displays single evoked action potentials > 30 μV in response to a single 20 μA current pulse. (E) Representative voltage transients recorded on RuOx and ITO microelectrode sites in response to a 20 μA current with pulse width of 200 μs.