What if we could solve the world’s energy needs from the tears of children? No, literally. OK, well, maybe not just children, but… Oh, read the whole thing. Excerpt:
The ability to generate electricity by applying pressure, known as direct piezoelectricity, is a property of materials such as quartz that can convert mechanical energy into electrical energy and vice versa. Such materials are used in a variety of applications ranging from resonators and vibrators in mobile phones to deep ocean sonars and ultrasound imaging. Bone, tendon and wood are long known to possess piezoelectricity.
“While piezoelectricity is used all around us, the capacity to generate electricity from this particular protein had not been explored. The extent of the piezoelectricity in lysozyme crystals is significant. It is of the same order of magnitude found in quartz. However, because it is a biological material, it is non toxic so it could have many innovative applications such as electroactive anti-microbial coatings for medical implants,” explained Aimee Stapleton, the lead author and an Irish Research Council EMBARK Postgraduate Fellow in the Department of Physics and Bernal Institute of UL.
Crystals of lysozyme are easy to make from natural sources. “The high precision structure of lysozyme crystals has been known since 1965,” said structural biologist at UL and co-author Professor Tewfik Soulimane.
“In fact, it is the second protein structure and the first enzyme structure that was ever solved,” he added, “but we are the first to use these crystals to show the evidence of piezoelectricity”.
According to team leader Professor Tofail Syed of UL’s Department of Physics, “Crystals are the gold-standard for measuring piezoelectricity in non-biological materials. Our team has shown that the same approach can be taken in understanding this effect in biology. This is a new approach as scientists so far have tried to understand piezoelectricity in biology using complex hierarchical structures such as tissues, cells or polypeptides rather than investigating simpler fundamental building blocks”.
The discovery may have wide reaching applications and could lead to further research in the area of energy harvesting and flexible electronics for biomedical devices. Future applications of the discovery may include controlling the release of drugs in the body by using lysozyme as a physiologically mediated pump that scavenges energy from its surroundings. Being naturally biocompatible and piezoelectric, lysozyme may present an alternative to conventional piezoelectric energy harvesters, many of which contain toxic elements such as lead.
You can read the entire paper here.
I could spend some time making jokes about generating power from tears, but that would be in poor taste (not that that has ever stopped me before.)
It’s hard for me to find a practical application for this, but a few do come to mind, mostly having to do with charging personal electronics. And bear in mind, that’s not an insignificant thing, given the small constellation of personal electronics that are apparently indispensable for our modern lives. But as the article notes, it is in the world of implantable medical devices that this could really make a difference. Implantable devices like intrathecal drug pumps and electronic spinal cord stimulators can make a huge difference in the lives of people with chronic pain issues, but these days they are run by batteries. And those batteries have to be replaced periodically.
Having them run by some sort of biological process would be somewhere past awesome.