Bioluminescent Christmas Trees? : Krulwich Wonders... A researcher has bioengineered a way to make a plant that glows by using gold nanoparticles. One day, we might be seeing gold-injected trees lighting up our streets.
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Bioluminescent Christmas Trees?

I know this is the season for many of you to buy a tree and cover it with little blinking lights. You should therefore know that a Dr. Yen-Hsun Su of the Research Center for Applied Science in Taiwan has just made this a whole lot easier. He has just bioengineered a way to make a tree that glows.

Gold nanoparticles mixed in with noncancerous cells. Georgia Tech hide caption

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Georgia Tech

Gold nanoparticles mixed in with noncancerous cells.

Georgia Tech

In fact, he's just made a luminescent plant. It's the real deal.

What he did is so weird, I can't quite believe it. Yen-Hsun is interested in traffic lights. He was trying to come up with a more efficient light emitting diode, presumably to enhance street lighting in Taiwan, and somewhere along the way he decided to dump the phosphor powder normally used in LEDs and switch to gold nanoparticles. Nanoparticles are really, really small. Then, (and I'm not sure why) he decided to implant the gold not onto a lamp, but into a living plant.

He chose the plant you see here. It's a common aquatic herb called Bacopa caroliniana.

When the gold went in, the leaves began to glow. The chlorophyll produced a "red emission" when exposed to ultraviolet light.

Trees that might one day glow. romana klee via flickr hide caption

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romana klee via flickr

Gold, in other words, got the plant to light up the way those deep sea creatures do at the bottom of the ocean.

The Taiwanese scientists now propose "to improve the efficiency of the bioluminescence and apply the technology to other biomolecules," meaning they plan to move on to bigger plants. In their paper they said they hoped to create trees along roads that one day could replace or enhance street lights.

What a notion! Gold-injected trees lighting up our streets.

One of my favorite bloggers, Geoff Manaugh of BLDGBLOG went into a kind of ecstasy at the thought of it:

That's right: glowing trees. The scientists who discovered it call it bio-LED ... 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.

I know what a lot of you are thinking and I'm thinking it too: What happens to our "streetlights" when the leaves fall off the trees? Can you do this with pine tree? A spruce? Wouldn't gold somehow hurt the tree? Or hurt the critters to eat the leaves? Who's going to want to inject a tree leaf by leaf? What would this cost? Do you have to place a UV light next to each tree to see the glow? Why are you taking this seriously?

Well, I have two answers. First, the Taiwanese have shown we can make plants glow, and that, for better or worse, is real news. And second, while all this will of course happen slowly, if it happens at all, even thinking about a living room on Christmas Eve, presents on the floor, everything quiet with a 6 foot tree glowing from within ... makes me smile.