Tag Archives: Basque Foundation for Science

Carbon nanotubes to repair nerve fibres (cyborg brains?)

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Can cyborg brains be far behind now that researchers are looking at ways to repair nerve fibers with carbon nanotubes (CNTs)? A June 26, 2017 news item on ScienceDaily describes the scheme using carbon nanotubes as a material for repairing nerve fibers,

Carbon nanotubes exhibit interesting characteristics rendering them particularly suited to the construction of special hybrid devices — consisting of biological issue and synthetic material — planned to re-establish connections between nerve cells, for instance at spinal level, lost on account of lesions or trauma. This is the result of a piece of research published on the scientific journal Nanomedicine: Nanotechnology, Biology, and Medicine conducted by a multi-disciplinary team comprising SISSA (International School for Advanced Studies), the University of Trieste, ELETTRA Sincrotrone and two Spanish institutions, Basque Foundation for Science and CIC BiomaGUNE. More specifically, researchers have investigated the possible effects on neurons of the interaction with carbon nanotubes. Scientists have proven that these nanomaterials may regulate the formation of synapses, specialized structures through which the nerve cells communicate, and modulate biological mechanisms, such as the growth of neurons, as part of a self-regulating process. This result, which shows the extent to which the integration between nerve cells and these synthetic structures is stable and efficient, highlights the great potentialities of carbon nanotubes as innovative materials capable of facilitating neuronal regeneration or in order to create a kind of artificial bridge between groups of neurons whose connection has been interrupted. In vivo testing has actually already begun.

The researchers have included a gorgeous image to illustrate their work,

Caption: Scientists have proven that these nanomaterials may regulate the formation of synapses, specialized structures through which the nerve cells communicate, and modulate biological mechanisms, such as the growth of neurons, as part of a self-regulating process. Credit: Pixabay

A June 26, 2017 SISSA press release (also on EurekAlert), which originated the news item, describes the work in more detail while explaining future research needs,

“Interface systems, or, more in general, neuronal prostheses, that enable an effective re-establishment of these connections are under active investigation” explain Laura Ballerini (SISSA) and Maurizio Prato (UniTS-CIC BiomaGUNE), coordinating the research project. “The perfect material to build these neural interfaces does not exist, yet the carbon nanotubes we are working on have already proved to have great potentialities. After all, nanomaterials currently represent our best hope for developing innovative strategies in the treatment of spinal cord injuries”. These nanomaterials are used both as scaffolds, a supportive framework for nerve cells, and as means of interfaces releasing those signals that empower nerve cells to communicate with each other.

Many aspects, however, still need to be addressed. Among them, the impact on neuronal physiology of the integration of these nanometric structures with the cell membrane. “Studying the interaction between these two elements is crucial, as it might also lead to some undesired effects, which we ought to exclude”. Laura Ballerini explains: “If, for example, the mere contact provoked a vertiginous rise in the number of synapses, these materials would be essentially unusable”. “This”, Maurizio Prato adds, “is precisely what we have investigated in this study where we used pure carbon nanotubes”.

The results of the research are extremely encouraging: “First of all we have proved that nanotubes do not interfere with the composition of lipids, of cholesterol in particular, which make up the cellular membrane in neurons. Membrane lipids play a very important role in the transmission of signals through the synapses. Nanotubes do not seem to influence this process, which is very important”.

There is more, however. The research has also highlighted the fact that the nerve cells growing on the substratum of nanotubes, thanks to this interaction, develop and reach maturity very quickly, eventually reaching a condition of biological homeostasis. “Nanotubes facilitate the full growth of neurons and the formation of new synapses. This growth, however, is not indiscriminate and unlimited since, as we proved, after a few weeks a physiological balance is attained. Having established the fact that this interaction is stable and efficient is an aspect of fundamental importance”. Maurizio Prato and Laura Ballerini conclude as follows: “We are proving that carbon nanotubes perform excellently in terms of duration, adaptability and mechanical compatibility with the tissue. Now we know that their interaction with the biological material, too, is efficient. Based on this evidence, we are already studying the in vivo application, and preliminary results appear to be quite promising also in terms of recovery of the lost neurological functions”.

Here’s a link to and a citation for the paper,

Sculpting neurotransmission during synaptic development by 2D nanostructured interfaces by Niccolò Paolo Pampaloni, Denis Scaini, Fabio Perissinotto, Susanna Bosi, Maurizio Prato, Laura Ballerini. Nanomedicine: Nanotechnology, Biology and Medicine, DOI: http://dx.doi.org/10.1016/j.nano.2017.01.020 Published online: May 25, 2017

This paper is open access.

Graphene and neurons in a UK-Italy-Spain collaboration

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There’s been a lot of talk about using graphene-based implants in the brain due to the material’s flexibility along with its other properties. A step forward has been taking according to a Jan. 29, 2016 news item on phys.org,

Researchers have successfully demonstrated how it is possible to interface graphene – a two-dimensional form of carbon – with neurons, or nerve cells, while maintaining the integrity of these vital cells. The work may be used to build graphene-based electrodes that can safely be implanted in the brain, offering promise for the restoration of sensory functions for amputee or paralysed patients, or for individuals with motor disorders such as epilepsy or Parkinson’s disease.

A Jan. 29, 2016 Cambridge University press release (also on EurekAlert), which originated the news item, provides more detail,

Previously, other groups had shown that it is possible to use treated graphene to interact with neurons. However the signal to noise ratio from this interface was very low. By developing methods of working with untreated graphene, the researchers retained the material’s electrical conductivity, making it a significantly better electrode.

“For the first time we interfaced graphene to neurons directly,” said Professor Laura Ballerini of the University of Trieste in Italy. “We then tested the ability of neurons to generate electrical signals known to represent brain activities, and found that the neurons retained their neuronal signalling properties unaltered. This is the first functional study of neuronal synaptic activity using uncoated graphene based materials.”

Our understanding of the brain has increased to such a degree that by interfacing directly between the brain and the outside world we can now harness and control some of its functions. For instance, by measuring the brain’s electrical impulses, sensory functions can be recovered. This can be used to control robotic arms for amputee patients or any number of basic processes for paralysed patients – from speech to movement of objects in the world around them. Alternatively, by interfering with these electrical impulses, motor disorders (such as epilepsy or Parkinson’s) can start to be controlled.

Scientists have made this possible by developing electrodes that can be placed deep within the brain. These electrodes connect directly to neurons and transmit their electrical signals away from the body, allowing their meaning to be decoded.

However, the interface between neurons and electrodes has often been problematic: not only do the electrodes need to be highly sensitive to electrical impulses, but they need to be stable in the body without altering the tissue they measure.

Too often the modern electrodes used for this interface (based on tungsten or silicon) suffer from partial or complete loss of signal over time. This is often caused by the formation of scar tissue from the electrode insertion, which prevents the electrode from moving with the natural movements of the brain due to its rigid nature.

Graphene has been shown to be a promising material to solve these problems, because of its excellent conductivity, flexibility, biocompatibility and stability within the body.

Based on experiments conducted in rat brain cell cultures, the researchers found that untreated graphene electrodes interfaced well with neurons. By studying the neurons with electron microscopy and immunofluorescence the researchers found that they remained healthy, transmitting normal electric impulses and, importantly, none of the adverse reactions which lead to the damaging scar tissue were seen.

According to the researchers, this is the first step towards using pristine graphene-based materials as an electrode for a neuro-interface. In future, the researchers will investigate how different forms of graphene, from multiple layers to monolayers, are able to affect neurons, and whether tuning the material properties of graphene might alter the synapses and neuronal excitability in new and unique ways. “Hopefully this will pave the way for better deep brain implants to both harness and control the brain, with higher sensitivity and fewer unwanted side effects,” said Ballerini.

“We are currently involved in frontline research in graphene technology towards biomedical applications,” said Professor Maurizio Prato from the University of Trieste. “In this scenario, the development and translation in neurology of graphene-based high-performance biodevices requires the exploration of the interactions between graphene nano- and micro-sheets with the sophisticated signalling machinery of nerve cells. Our work is only a first step in that direction.”

“These initial results show how we are just at the tip of the iceberg when it comes to the potential of graphene and related materials in bio-applications and medicine,” said Professor Andrea Ferrari, Director of the Cambridge Graphene Centre. “The expertise developed at the Cambridge Graphene Centre allows us to produce large quantities of pristine material in solution, and this study proves the compatibility of our process with neuro-interfaces.”

The research was funded by the Graphene Flagship [emphasis mine],  a European initiative which promotes a collaborative approach to research with an aim of helping to translate graphene out of the academic laboratory, through local industry and into society.

Here’s a link to and a citation for the paper,

Graphene-Based Interfaces Do Not Alter Target Nerve Cells by Alessandra Fabbro, Denis Scaini, Verónica León, Ester Vázquez, Giada Cellot, Giulia Privitera, Lucia Lombardi, Felice Torrisi, Flavia Tomarchio, Francesco Bonaccorso, Susanna Bosi, Andrea C. Ferrari, Laura Ballerini, and Maurizio Prato. ACS Nano, 2016, 10 (1), pp 615–623 DOI: 10.1021/acsnano.5b05647 Publication Date (Web): December 23, 2015

Copyright © 2015 American Chemical Society

This paper is behind a paywall.

There are a couple things I found a bit odd about this project. First, all of the funding is from the Graphene Flagship initiative. I was expecting to see at least some funding from the European Union’s other mega-sized science initiative, the Human Brain Project. Second, there was no mention of Spain nor were there any quotes from the Spanish researchers. For the record, the Spanish institutions represented were: University of Castilla-La Mancha, Carbon Nanobiotechnology Laboratory, and the Basque Foundation for Science.