A new electronic material has been developed to record neural networks over long periods of time has been developed. Klas Tybrandt is the principal investigator at the Laboratory of Organic Electronics at Linkoping University and the key researcher behind this new technology. The electronics is based on a novel elastic material composite. This composite is biocompatible and can retain high electrical conductivity when stretched to almost twice its natural size.
Biotechnology is one of the biggest growing industries. The medical field is always looking for ways to use technology to help doctors and patients ease things like health tracking or procedures. This new technology couples electronic components and nerve cells. This is important because it can collect information about cell signaling as well as diagnose and treat neurological disorders and diseases.
One of the biggest challenges behind long-term stable connection is developing a technology that won't damage neurons or tissues. This is usually because the rigid electronics and the soft elastic body tissue have two opposing mechanical properties.
"As human tissue is elastic and mobile, damage and inflammation arise at the interface with rigid electronic components. It not only causes damage to tissue; it also attenuates neural signals," says Tybrandt.
Tybrandt has developed a new material that solves this problem. The conductive material is soft like human tissue and can also be stretched to twice its length. It is made out of gold coated titanium dioxide nanowires that are embedded into silicon rubber, all while being biocompatible and maintaining stability.
"The microfabrication of soft electrically conductive composites involves several challenges. We have developed a process to manufacture small electrodes that also preserves the biocompatibility of the materials. The process uses very little material, and this means that we can work with a relatively expensive material such as gold, without the cost becoming prohibitive," says Tybrandt.
The electrodes measure at 50 μm and are placed a distance of 200 μm away from each other with 32 electrodes on the entire small surface. The final probe is 3.2 mm and 80 μm thick.
Through testing, the researchers found that they could collect neural signals from freely moving rats for three months. This shows promise for the technology being used in humans.
"When the neurons in the brain transmit signals, a voltage is formed that the electrodes detect and transmit onwards through a tiny amplifier," says Tybrandt. "We can also see which electrodes the signals came from, which means that we can estimate the location in the brain where the signals originated. This type of spatiotemporal information is important for future applications. We hope to be able to see, for example, where the signal that causes an epileptic seizure starts, a prerequisite for treating it. Another area of application is brain-machine interfaces, by which future technology and prostheses can be controlled with the aid of neural signals. There are also many interesting applications involving the peripheral nervous system in the body and the way it regulates various organs."
A paper on this research was published in Advanced Materials.