Engineering news
An international group created soft cells using hydrogel and salt to form an ‘artificial electric organ’ that can generate more than 100V.
It could produce enough power to run a small medical device such as a pacemaker, or be used for implanted health monitors, medication dispensers, or augmented-reality contact lenses. In future, it could also be used to generate electricity from naturally occurring processes within the body.
"The eel polarises and depolarises thousands of cells instantaneously to put out these high voltages," said Max Shtein, a professor of materials science and engineering at the University of Michigan and a co-author of the study, which was published in the journal Nature. “It's a fascinating system to look at from an engineering perspective – its performance metrics, its fundamental building blocks and how to use them.”
An electric eel’s specialised organs contain thousands of compartments that keep potassium and sodium ions separate, and then allow them to flow together when required to create a jolt of electricity.
The researchers, from Michigan, Fribourg in Switzerland and the University of California, San Diego, built a similar system using sheets of hydrogels and sodium and chloride ions, and created a way of folding them in precise patterns to create coordinated bursts of power.
“The electric organs in eels are incredibly sophisticated; they're far better at generating power than we are," said Michael Mayer, a professor of biophysics at the University of Fribourg. "But the important thing for us was to replicate the basics of what's happening.”
The system only creates a small current, but that shouldn’t be a problem, according to Niko Munzenrieder, an expert in flexible electronics from the University of Sussex who was not involved in the research. “Some applications, such as the pacemaker, brain implants for Parkinson’s disease patients, or piezoelectric actuators, require only low currents but high voltages, and in the end what counts is the power which means you can always convert voltage into current using appropriate circuitry,” he told PE.
Content published by Professional Engineering does not necessarily represent the views of the Institution of Mechanical Engineers.