Intracellular action potential recordings from cardiomyocytes by ultrafast pulsed laser irradiation of fuzzy graphene microelectrodes

Graphene with its unique electrical properties is a promising candidate for carbon-based biosensors such as microelectrodes and field effect transistors. Recently, graphene biosensors were successfully used for extracellular recording of action potentials in electrogenic cells; however, intracellular recordings remain beyond their current capabilities because of the lack of an efficient cell poration method. Here, we present a microelectrode platform consisting of out-of- plane grown three-dimensional fuzzy graphene (3DFG) that enables recording of intracellular cardiac action potentials with high signal-to-noise ratio. We exploit the generation of hot carriers by ultrafast pulsed laser for porating the cell membrane and creating an intimate contact between the 3DFG electrodes and the intracellular domain. This approach enables us to detect the effects of drugs on the action potential shape of human-derived cardiomyocytes. The 3DFG electrodes combined with laser poration may be used for all-carbon intracellular microelectrode arrays to allow monitoring of the cellular electrophysiological state.

Automated summary

Researchers have successfully recorded intracellular cardiac action potentials with high signal-to-noise ratio using a microelectrode platform made of three-dimensional fuzzy graphene (3DFG). By utilizing ultrafast pulsed laser for porating the cell membrane, an intimate contact between the 3DFG electrodes and the intracellular domain was created, enabling the detection of drug effects on human-derived cardiomyocytes' action potential shape. This approach may be applied to monitor cellular electrophysiological states, especially for studying the impact of drugs on cardiac cells.