Richard Kaner, PhD
For patients with pacemakers and other implantable medical devices, there is no lifetime guarantee on the technology. That's why researchers at UCLA and the University of Connecticut have been working on creating a new technology that can run on the energy of fluids — straight from the human body.
"In theory, it is actually possible to make devices that will last a lifetime," says Dr. Richard Kaner, PhD, a professor of chemistry and biochemistry, and materials science and engineering at UCLA. "The problem is they need to be bio-compatible and they need a power source. That's how we became interested in bio-supercapacitors."
Reinventing the battery
Traditional implantable medical devices, such as pacemakers, are powered by batteries that have a lifespan of approximately 10 years. This means surgery is inevitable, simply because the battery needs replacing. But thanks to a team of researchers led by Dr. Kaner, battery-powered pacemakers may eventually become a thing of the past.
The team invented a new energy-storage device, called a biological supercapacitor. It is long-lasting, non-toxic and ultra thin. The device is made of graphene (a thin layer of pure carbon) and human proteins that act as electrodes, and gets its charge from electrolytes found in blood serum and urine. Dr. Kaner's paper about the device was first published in July 2015 in the journal Advanced Energy Materials.
Unlike batteries, supercapacitors are often limited by low energy densities, so the research focused on designing a device that would capture energy effectively and be compatible with the human body.
"We call it laser-scribed graphene and that enables one to actually make a storage device that stores all its energy on the surface," says Dr. Kaner. "It has no expansion and no contraction and therefore you can literally go millions of cycles with this new type of energy storage cell."
There's a long road ahead
Dr. Kaner's paper argues that the bio-supercapacitor is not only a viable form of power, but that it can in fact store a comparable amount of charge to lithium ion batteries — while lasting much longer. Unfortunately, as Dr. Kaner explains, the biological supercapacitor is still a long way from being used for implantable medical devices.
"There are a lot of approval processes and all sorts of safety testing. This paper is really a proof-of-concept, showing that this is possible," Dr. Kaner says. "But often once you show something is possible, there are a lot of people in the biomedical area and a lot of biomedical device companies that may become interested and decide this is worth pursuing."
