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Carbon-based materials

Carbon materials are more bioinert than traditional metals and semiconductors. We use graphene, diamond, and organic conductive polymers to fabricate microelectrode arrays (MEAs) and field effect transistors (FETs). Such devices can be fabricated on other flexible and organic substrates, like PDMS, polyimide or parylene-C. The devices possess both: (i) flexibility and biocompatibility for in vivo studies; (ii) great electrical performance allowing recording of single neuronal action potentials.


Carbon nanotubes covered with diamond were investigated for their biocompability and usage as an electrode material. The advantages of this 3D material are the stability and inertness, but also its large surface area and wide electrochemical window. The cell adhesion to the substrates is investigated using focused ion beam cuts through the cell.

Graphene for bioelectronics

Graphene itself is a fascinatingly interesting material to work with. Regardless the already discovered physical and electrical properties, it still possess qualities which are well suitable for biology. Bio-affinity, stability, flexibility and transparency bring graphene to a very special place as material for bioelectronics. Here, we use CVD-grown graphene, transferred on top of SiO2/Si substrates and patterned to form stripes as a template for neuronal growth. Interestingly, the neurons “feel” the graphene surface and follow their growth along the graphene edges. Moreover, optimizing graphene’s surface charge concentrations, one can change cellular adhesion/repulsion.

Graphene Devices


Graphene-based MEAs and transistors are of great interest, due to their extreme sensitivity, biocompatibility, and possible flexibility. They can achieve this because as a 2D material the surface effects far outweigh properties of the bulk. That means transistors with graphene gates exhibit extreme sensitivity to the surface potential changes (which are action potentials produced by the electrogenic cells). We fabricate the devices using monolayer CVD-grown graphene on different substrates. The cardiac and neuronal cellular activity can be recorded via these devices.

Conductive Polymers

The conducting polymer poly(3,4-ethylenedioxythiophene): poly(styrene sulfonate) (PEDOT:PSS) has been considered a promising candidate as a printable electrode material due to its mechanical flexibility, solution process-ability, and biocompatibility. We use PEDOT:PSS mainly as a channel material in an organic electrochemical transistor for neuronal recordings.

Additional Information


Prof. Dr. Andreas Offenhäusser
Tel.:  +49-2461-61-2330

Dr. Vanessa Maybeck
Tel.:  +49-2461-61-3285

Dr. Dirk Mayer
Tel.:  +49-2461-61-4023

More Information


High throughput transfer technique: Save your graphene
Kireev et al., Carbon N. Y., vol. 107, pp. 319–324, 2016.

Verfahren zum Transfer von Graphen-Stuecken auf ein Substrat
Deutsche Patentanmeldung 10201516143.1

Electrolyte-Gated Graphene Ambipolar Frequency Multipliers for Biochemical Sensing
Fu et al., Nano Lett., vol. 16, no. 4, pp. 2295–2300, 2016.

Graphene transistor arrays for recording action potentials from electrogenic cells
Hess et al., Adv. Mater., vol. 23, no. 43, pp. 5045–9, 4968, 2011

Graphene transistors for in-vitro and ex-vivo recordings  Kireev et al.,  IEEE transactions on Nanotechnology 16, pp.140-147, 2016;

Versatile flexible graphene microelectrode arrays Kireev et al., Biosensors 7, p. 1-9, 2017;

Graphene multi electrode arrays as a versatile tool for extracellular recordings Kireev et al.,  Adv. Healthcare Mater. 2017, 1601433.