Biosensors with Graphene Transistors
In the future, bioelectronic implants could replace damaged sensory cells, enabling the blind or deaf to see and hear. Researchers at the Technische Universität München (TUM) and Forschungszentrum Jülich have demonstrated that graphene-based microelectronics could be a route to developing such devices.
The silicon-based technology currently used poses serious problems at the interface between the device and living cells, as silicon does not adapt well to the flexibility or wet environment of biological cells. Moreover, previous implants were many times larger than the nerve cells with which they were meant to communicate.
Graphene could prove a more suitable alternative. Essentially, it is made up of a two-dimensional network of carbon atoms, offers superior electronic performance, is chemically stable and biocompatible. It can easily be processed into a flexible foil and should be cheap to manufacture on a large scale. Furthermore, it shows high biocompatibility.
During the study, scientists were able to grow heart muscle cells over graphene transistors of a similar size to a single cell. Subsequently, with these simple biosensors, they determined the ‘action potentials’ generated by the cells, registering significantly less background noise than silicon-based technology would produce. Further research and development of graphene elements is already being planned; the group is studying possible applications for brain implants as part of its research undertaken within the broad-based European project NEUROCARE.
Graphene Transistor Arrays for Recording Action Potentials from Electrogenic Cells Lucas H. Hess, Michael Jansen, Vanessa Maybeck, Moritz V. Hauf, Max Seifert, Martin Stutzmann, Ian D. Sharp, Andreas Offenhaeusser and Jose A. Garrido Advanced Materials 2011, 23, 5045-5049
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