Finding ways to connect the human body to technology could have wide-ranging applications in health and entertainment. New “electroplastics” could make self-powered wearables, real-time neural interfaces, and medical implants that integrate with our bodies a reality.
Although significant progress has been made in the development of wearable and implantable technologies in recent years, most electronic materials contain hard, hard, and toxic metals. A variety of approaches to creating “soft electronics” have emerged, but finding an approach that is durable, power efficient, and easy to manufacture is a significant challenge.
Organic ferroelectric materials are promising because they exhibit spontaneous polarization. This means that it has a stable electric field pointing in a specific direction. This polarization can be reversed by applying an external electric field, allowing it to act like a bit in a conventional computer.
The most successful soft ferroelectric is a material called polyvinylidene fluoride (PVDF), which has been used in commercial products such as wearable sensors, medical imaging, underwater navigation devices, and soft robots. However, the electrical properties of PVDF can decompose when exposed to higher temperatures, and high voltages are required to reverse polarization.
Now, in a paper published in natureResearchers at Northwestern University have shown that combining this material with short chains of amino acids, known as peptides, can dramatically reduce power requirements and increase heat resistance. And incorporating biomolecules into materials opens up the possibility of connecting electronic devices directly with the body.
To create the new “electroplastic,” the team used a type of molecule known as a peptide amphiphile. These molecules have water-repellent properties that help them self-assemble into complex structures. The researchers linked these peptides to short strands of PVDF and exposed them to water, causing the peptides to clump together.
This caused the strands to merge into long, flexible ribbons. In tests, the team found that the material could withstand temperatures of 110 degrees Celsius, about 40 degrees higher than previous PVDF materials. Switching the polarity of this material also required significantly lower voltages, despite the fact that 49% of its weight is made up of peptides.
researchers said science Not only can energy or information be stored in the polarization of the material, but it is also biocompatible. This means it can be used in everything from wearable devices that monitor vital signs to flexible implants that can replace pacemakers. Peptides can also link to proteins inside cells to record or even stimulate biological activity.
One challenge is that although PVDF is biocompatible, it can degrade into so-called “forever chemicals.” These chemicals remain in the environment for centuries and studies have linked them to health and environmental problems. Several other chemicals that researchers have used to manufacture substances also fall into this category.
“These advances allow for a number of attractive properties compared to other organic polymers,” said Frank Leibfarth of UNC Chapel Hill. science. But he noted that researchers have only tested very small amounts of the molecule and it’s unclear how easy it would be to scale it up.
But if researchers can scale this approach to larger scales, it could bring about a host of exciting new possibilities at the interface between our bodies and technology.
Image credit: Mark Seniw/Center for Regenerative Nanomedicine/Northwestern University
