An anonymous reader quotes a report from Science Magazine:

> Imagine a thin wristband that monitors your steps and heartbeat like an Apple Watch. Or clothing that keeps you cool with built-in air conditioning. Or even a flexible implant that could help your heart better than a bulky pacemaker. That's the promise of a [1]new, electrically active material researchers have created by combining short chains of amino acids called peptides with snippets of a polymer plastic. This "electric plastic," [2]reported this month in Nature , can store energy or record information, opening the door to self-powered wearables, real-time neural interfaces, and medical implants that merge with bodies better than current tech. [...]

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> Samuel Stupp, a materials scientist at Northwestern University, and his colleagues thought they could improve on polyvinylidene fluoride's (PVDF) properties. The team connected peptides with small PVDF segments, which naturally assembled into long, flexible ribbons. The molecules then coalesced into bundles and aligned to form an electro-active material. "Remarkably," Stupp says, "the self-assembly process is triggered by adding water." The new material overcomes PVDF's limitations. It requires 100 times less voltage to switch polarization compared with other ferroelectric materials, making it ideal for low-power applications. And it retains its ferroelectric properties at temperatures of 110C -- about 40C higher than other PVDF materials.

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> Stupp's new material can store energy or information by electrically switching the polarity of each ribbon. And because the peptide on the end of each ribbon can be connected to proteins on neurons or other cells, the molecules can record the signals from the brain, heart, or other organs -- or electrically stimulate them. By using low-power techniques like ultrasound to "charge" the molecules, the material could be used to stimulate neurons as a treatment for chronic paralysis, Stupp says. Study co-author Yang Yang, an electrical power engineer at Northwestern, notes that PVDF is biocompatible, making the material a promising candidate for soft implants that could be wirelessly controlled from outside the body.

Stupp's team has conducted small-scale evaluations of molecules, but scaling up will require placing water-suspended structures onto devices without altering them -- a challenge noted by chemist Frank Leibfarth. Even with this hurdle, "This advance has enabled a number of attractive properties compared to other organic polymers," he says.

Stupp added: "This paper has a much broader concept than just vinylidene fluoride. There probably are other possibilities ... that don't have fluorine."



[1] https://www.science.org/content/article/electric-plastic-could-open-door-new-generation-implants-and-wearable-tech

[2] https://www.nature.com/articles/s41586-024-08041-4