Archive for the ‘graphene’ Category

Scientists have long been on a quest to find a way to implant electrodes that interface with neurons into the human brain. If successful, the idea could have huge implications for the treatment of Parkinson’s disease and other neurological disorders. Last month, a team of researchers from Italy and the UK made a huge step forward by showing that the world’s favorite wonder-material, graphene, can successfully interface with neurons.

Previous efforts by other groups using treated graphene had created an interface with a very low signal to noise ratio. But an interdisciplinary collaborative effort by the University of Trieste and the Cambridge Graphene Centre has developed a significantly improved electrode by working with untreated graphene.

“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 signaling properties unaltered. This is the first functional study of neuronal synaptic activity using uncoated graphene based materials.”

Prior to experimenting with graphene-based substrates (GBS), scientists implanted microelectrodes based on tungsten and silicon. Proof-of-concept experiments were successful, but these materials seem to suffer from the same fatal flaws. The body’s reaction to the insertion trauma is to form scarring tissue, inhibiting clear electrical signals. The structures were also prone to disconnecting, due to the stiffness of the materials, which were unsuitable for a semi-fluid organic environment.

Pure graphene is promising because it is flexible, non-toxic, and does not impair other cellular activity.

The team’s experiments on rat brain cell cultures showed that the untreated graphene electrodes interfaced well with neurons, transmitting electrical impulses normally with none of the adverse reactions seen previously.

The biocompatibility of graphene could allow it to be used to make graphene microelectrodes that could help measure, harness and control an impaired brain’s functions. It could be used to restore lost sensory functions to treat paralysis, control prosthetic devices such a robotic limbs for amputees and even control or diminish the impact of the out-of-control electrical impulses that cause motor disorders such as Parkinson’s and epilepsy.

“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 bio-devices requires the exploration of the interactions between graphene nano and micro-sheets with the sophisticated signaling machinery of nerve cells. Our work is only a first step in that direction.”

The results of this research were recently published in the journal ACS Nano. The research was funded by the Graphene Flagship, a European initiative that aims to connect theoretical and practical fields and reduce the time that graphene products spend in laboratories before being brought to market.

http://www.cam.ac.uk/research/news/graphene-shown-to-safely-interact-with-neurons-in-the-brain

A Feb. 21, 2013 article in Rewire reports on a breakthrough in power storage that hold the promise to change the world. Researchers at UCLA have found a way to create what is in effect a super capacitor that can be charged quickly and will hold more electricity than standard batteries. What’s more, it is made with Graphene, a simply carbon polymer that, unlike batteries that have toxic metals in them, is environmentally benign and is not only biodegradable but compostable.

The researchers expect that the manufacturing process for the Graphene super capacitor can be refined for mass production.

The real world applications of an energy storage device that can be charged quickly and can hold as much if not more electricity as batteries is mind blowing.

For instance, electronic devices such as cell phones and tablet computers can be charged in seconds and not for hours and would hold a charge for longer than devices with standard batteries. This will diminish those annoying instances when one’s device suddenly goes dead for lack of energy.

Eventually the technology can be scaled up for electric cars or storage devices for wind turbines and solar collectors. Currently it takes hours to charge up an electric car. Such vehicles would become more viable if one can “refuel” them as quickly as one can a gasoline powered car.

This is all predicated on the notion that the technology lives up to its promise and doesn’t have a flaw, as yet uncovered, that will undermine it. In the meantime the UCLA researchers are looking for an industrial partner to build their super capacitor units on an industrial scale.

http://www.examiner.com/article/graphene-super-capacitor-could-make-batteries-obsolete