Nanotubes help neurons get chatty
Small stuff, big potential
Italian researchers have managed to persuade brain cells to grow on a nanotube-coated surface - a breakthrough that could provide immediate help to good, old humans. The team found that the nanotubes actually boosted communication, or neural signal transfer, between the cells, which were taken from the hippocampus.
The research was prompted by the structural similarity of carbon nanotubes and neurons, according to a NanotechWeb report. "Neurite elongations [projections from nerve cells, such as the sciatic nerve or dendrites - Ed] are reminiscent of the cylindrical shape of carbon nanotubes," Laura Ballerini of the University of Trieste told the publication.
Along with her colleague, Maurizio Prato, she explained that this similarity, in combination with the carbon nanotubes's property of being conducting or semi-conducting, means that in principle, the tubes could be used to help reconnect non-communicating neurons, both structurally and functionally.
The nanotubes were processed so that they could be encouraged to dissolve in the organic solvent dimethylformamide. Drops of the resulting solution were placed on glass cover slips. Once the solvent had evaporated, the glass was heated, resulting in a glass substrate coated with nanotubes.
Once the surface was ready, the hippocampal neurons were attached to glass cover slips with and without nanotube coatings. Over the next ten days, the neurons grew similarly on either surface, and showed similar characteristics such as resting membrane potential, input resistance and capacitance. They also had similar intrinsic excitability.
However, frequency of post synaptic currents showed a six-fold increase in the neurons grown on nanotubes, compared to those grown on glass, demonstrating a significant improvement in the effectiveness of the neural signal.
The researchers say the breakthrough could have an immediate impact on the treatment of spinal cord injury, and in the design of chronic neural implants. ®