Graphene oxide electrodes enable electrical stimulation of distinct calcium signalling in brain astrocytes.

Astrocytes are responsible for maintaining homoeostasis and cognitive functions through calcium signalling, a process that is altered in brain diseases. Current bioelectronic tools are designed to study neurons and are not suitable for controlling calcium signals in astrocytes. Here, we show that electrical stimulation of astrocytes using electrodes coated with graphene oxide and reduced graphene oxide induces respectively a slow response to calcium, mediated by external calcium influx, and a sharp one, exclusively due to calcium release from intracellular stores.

Strain Engineering in Highly Wrinkled CVD Graphene/Epoxy Systems.

Chemical vapor deposition (CVD) is regarded as a promising fabrication method for the automated, large-scale, production of graphene and other two-dimensional materials. However, its full commercial exploitation is limited by the presence of structural imperfections such as folds, wrinkles, and even cracks that downgrade its physical and mechanical properties. For example, as shown here by means of Raman spectroscopy, the stress transfer from an epoxy matrix to CVD graphene is on average 30% of that of exfoliated monolayer graphene of over 10 μm in dimensions.

Turning an organic semiconductor into a low-resistance material by ion implantation.

We report on the effects of low energy ion implantation on thin films of pentacene, carried out to investigate the efficacy of this process in the fabrication of organic electronic devices. Two different ions, Ne and N, have been implanted and compared, to assess the effects of different reactivity within the hydrocarbon matrix. Strong modification of the electrical conductivity, stable in time, is observed following ion implantation.