Gold is the Metal

[Image: Gold nanoparticles, courtesy of Georgia Tech].

It was reported earlier this month that "gold nanoparticles can induce luminescence in leaves." That's right: glowing trees. The scientists who discovered it call it bio-LED.

According to ElectroIQ, "by implanting the gold nanoparticles into Bacopa caroliniana plants, Dr. Yen-Hsun Su [of the Research Center for Applied Science in Taiwan] was able to induce the chlorophyll in the leaves to produce a red emission. Under high wavelength of ultraviolet, the gold nanoparticles can produce a blue-violet fluorescence to trigger a red emission of the surrounding chlorophyll."

This has the exquisitely surreal effect of being able "to make roadside trees luminescent at night"—with the important caveat "that the technologies and bioluminescence efficiency need to be improved for the trees to replace street lights in the future." In other words, we're not quite there—but a deciduous splendor might illuminate streets near you, soon.

[Image: Gold nanoparticles, courtesy of Georgia Tech].

Last spring, I should point out, I had the pleasure of teaching a research seminar at the Pratt Institute in Brooklyn, looking at blackouts: that is, landscapes—both urban and otherwise—encountered in a state of unexpected darkness.

We looked at a huge variety of technologies for non-electrical illumination—sources of light for situations in which electricity has failed—from tools as basic as pocket lighters to openly whimsical investigations into bioluminescent fish, plants, algae, and bacteria, scaled up to intimations of an entire bioluminescent metropolis.

But the idea that trees impregnated with gold might someday line city streets, turning night into day, is like a vision of Gustav Klimt unexpectedly crossed with Con Edison: a botanical alchemy through which base wood becomes light at the speed of photosynthesis.

(Via Popular Science; earlier: Three Trees).