The technology enables completely new types of implants that can be used to stimulate nerve cells and has been developed in a Joint effort by researchers from TU Graz, Med Uni Graz, University of Zagreb and CEITEC (Central European Institute of Technology) developed. The basis for this are color pigments from the food industry, such as those used in organic solar cells. The pigments are vapour-deposited to form a layer just a few nanometers thick, where they convert light into an electrical charge, just like in organic solar cells. Nerve cells that adhere to the foil (they are first pipetted onto the foil, “wander” on it and grow firmly, note), react to this charge and in turn fire electrical impulses with which they stimulate other nerve cells. In cell biological experiments, the researchers have now been able to demonstrate this process for the first time.
Paradigm shift from metal electrodes to flexible foils
Corresponding Author Theresa Rienmüller from the Institute for Health Care Engineering at Graz University of Technology speaks of a paradigm shift: “In contrast to the current electrical stimulation using metal electrodes, our pigment foils represent a completely new way of stimulating nerve cells.” The foils are so thin that they can be easily implanted. During the treatment, the nerve cells would then be irradiated with red light, which can penetrate deep into the body without harm. “We think that short-term treatments can lead to long-term therapeutic effects. These experiments are being researched right now.” Rainer Schindleelectrophysiologist at the Chair of Biophysics at Med Uni Graz and supervisor in the project.
In the future, there will no longer be any need for complex cabling, which in turn reduces the risk of infection following invasive procedures because there are no longer any hoses or cables that have to run out of the body to the outside. Thanks to their organic nature, the pigment foils are extremely well tolerated by both human and animal cells.
Diverse areas of application
The researchers see possible applications in severe brain injuries. Here, the stimulation of nerve cells can accelerate the healing process and prevent complications by “preventing the nerve cells from dying off,” according to lead author Tony Schmidt from the Chair of Biophysics at Med Uni Graz. The researchers also see potential in other neurological injuries or in pain therapy. The technology can also be used to create novel retinal implants.
