[LINK] "Plants, Electrified: Scientists Just Grew Conductive Wires Inside Real Roses"

[rfmcdonald]

William Herkewitz's Popular Mechanics article shares news of a technology of astonishing power and beauty.

Today scientists have taken a surprising leap toward actually integrating living plants into human electronics and power systems: A team of Swedish botanists and electrical engineers unveiled a fascinating method of growing and powering conductive wires inside living plants.

Led by Eleni Stavrinidou—a bioelectronic engingeer at Linköping University in Linköping, Sweden—the scientists employed a transparent, conductive gel that cut roses could naturally soak up into their stems and leaves. After a few hours, the gel material would harden and form flexible wires inside the plants' stems. Thanks to the fantastic properties of the plant-embedded wires, electric current could even be run through the wired stems, without (as far as the scientists could tell) damaging the plants.

"Although many attempts have been made to augment plant function with electroactive materials, [until now] plants' 'circuitry' has never been directly merged with electronics," writes the reseach team. The scientists describe their curious, bionic vegetation today in a remarkably titled science paper —"Electronic plants"—in the journal Science Advances.

Stavrinidou's research team tested countless conductive materials before they came across a winner. Their aim was to get plants to soak up materials that could later harden into wires through the plants xylem, the vein-like system a plant uses to transport water and nutrients. However, most materials (for example, two molecules called pyrrole and aniline) either simply wouldn't uptake, proved toxic when it came down to the hardening phase, or would clog the xylem. In the end, the winning material was a transparent, organic polymer that basically acts like conductive plastic. It's a flavor of a material called PEDOT—short for poly(3,4-ethylenedioxythiophene).

The research team also discovered that rose leaves, when submerged in PEDOT gel, also could uptake the material into a cell layer called the spongy mesophyll. After the PEDOT hardened into a conductive layer, the infused leafs could be introduced to electric current, reversibly darkening and lightening the leaf. While the molecular reason for this color change is still not fully understood, the scientists noted that the PEDOT-infused leafs could be kept alive just as long as unaffected rose leaves.