Tag Archives: firefly

glowing-plants

Glowing plants imbued with firefly enzymes might one day replace lamps

glowing-plants

Credit: Melanie Gonick/MIT.

Your bedpost plants might one day double as a reading lamp if MIT’s latest proect ever takes off. The team, which specializes in nanobionics, embedded nanoparticles into the watercress plant (Nasturtium officinale) to make it glow in a dim light. MIT hopes that this proof of concept one day makes its way into our homes and even replaces street lighting with glowing trees.

“The vision is to make a plant that will function as a desk lamp — a lamp that you don’t have to plug in,” said Michael Strano, Professor of Chemical Engineering at MIT and senior author of the study, in a statement. “The light is ultimately powered by the energy metabolism of the plant itself.”

To make plants glow, MIT engineers turned to luciferase — the oxidative enzymes that produce bioluminescence lending glowing abilities to animals like fireflies or certain mushroom species. Luciferase catalyzes a compound called luciferin which is what generates the light. Another molecule called co-enzyme A removes reaction byproducts that inhibit luciferase activity.

Previously, Vanderbilt University scientists employed a modified version of luciferase to make brain cells glow in the dark. 

All of these three components were packaged into carriers that balance light and toxicity, submerged in a solution, then exposed to high pressure to force the particles into the stomata pores of leaves. This way, watercress plants were able to expel a dim light for almost four hours before the compounds wore off, as reported in the journal Nano Letters.

Next, the team plans on refining its technique to make plants glow for a longer time. The firefly-compounds could potentially be incorporated in a spray so that basically any plant can be coaxed to emit light. So far, MIT demonstrated the luciferase compounds in plants like watercress, arugula, kale, and spinach.

Such technology could one day prove as a useful alternative to conventional products for low-intensity indoor lighting. In some places, streets lamps could be replaced by glowing trees, for instance, thus reducing our energy consumption and carbon footprint.

“Plants can self-repair, they have their own energy, and they are already adapted to the outdoor environment,” Strano says. “We think this is an idea whose time has come. It’s a perfect problem for plant nanobionics.”

fireflies glow

New firefly species from California discovered by undergrad student

Despite what you might have seen or not seen, there are actually some fireflies living west of the Rocky Mountains, though they mostly keep to themselves and are rarely spotted by humans. Every once in a while, people spot some. This time, one undergrad who was busy insect hunting in the Los Angeles County hit the jackpot after he discovered a new firefly species.

fireflies glow

Fireflies enchant a dark sunken forest. Image: Elephant Journal

Joshua Oliva, an undergraduate student at the University of California-Riverside was casually collecting insects in the Santa Monica Mountains for an entomology class. He even brought his mother along since she was very curious to learn what her son was actually studying. When Oliva found fireflies, he was ecstatic, but he had no clue yet what he came across.

“He wasn’t 100 percent certain it was a firefly, and brought it to me for confirmation,” says Doug Yanega, senior scientist at the UC-Riverside Entomology Research Museum, in a press release about the discovery. “I know the local fauna well enough that within minutes I was able to tell him he had found something entirely new to science. I don’t think I’ve seen a happier student in my life.”

People living in the East are truly blessed for they often get to see the insects flash during the twilight. In Florida, no fewer than 56 firefly species can be found. In California, there are only 18 known species. Moreover, they’re dim both in numbers and brightness. Not all fireflies in California glow (gotta wonder why they’re still called fireflies in the first place), and those which do only fly for a brief period after dusk. So, it’s no wonder that finding a new firefly species in California is big news!

“One reason we are bringing this discovery to the public’s attention is that it seems likely that this beetle may be highly restricted in distribution,” Yanega says, “and the habitat where it occurs may require consideration for some level of protection, at least until we can learn more about it.”

butterfly

This is the new insect species discovered by young Joshua Oliva. Image: UC Riverside

The new species, which doesn’t yet have a name, is half an inch long and all covered in black. One distinctive feature is its head “armor” which is marked with a orange-like halo.

What makes a firefly glow

One reason that fireflies glow is to attract a mate. Males and females of the same species will flash signals back and forth as a way of communicating. Each firefly species has its own particular pattern. For example, the fireflies of one species will fly around in the night sky and dive steeply just as the flash begins and turn upward to make a distinctive J-shaped pattern of light. Female fireflies hang out on a tree branch or in the grass while the males fly around showing off their best flashes. When a female recognizes the flash from a male of the same species, she will answer with her best flash.

The light itself is a form of bioluminescence. When oxygen combines with calcium, adenosine triphosphate (ATP) and the chemical luciferin in the presence of luciferase, a bioluminescent enzyme, light is produced. This process if highly efficient and results in what’s called “cold” light. A light bulb, on the other hand, emits “hot” light because it releases a lot of heat in the process.

Oliva graduated from UC-Riverside earlier this month. School’s far from over though. He intends on applying for the graduate program to go on to become an entomologist.

Misfit scales found on the lantern of the Photuris firefly. (c) Optical Express

Natural brightness: fireflies inspire LEDs with 55% more efficiency

A firefly specimen from the genus Photuris, which is commonly found in Latin America and the United States and served as the inspiration for the effective new LED coating. Credit: Optics Express.

A firefly specimen from the genus Photuris, which is commonly found in Latin America and the United States and served as the inspiration for the effective new LED coating. Credit: Optics Express.

We’ve featured countless research here on ZME Science where important scientific and technological advancements were made after scientists sought inspiration from nature, be them  high-tech surfaces (butterfly) or robots (leaping lizard). Recently, researchers at Canada’s University of Sherbrooke managed to improve LED efficiency by 55% after they applied a coating etched with a profile similar to that of firefly scales.

Fireflies emit the light for which they’re so recognized and loved through a chemical reaction that takes place in specialized cells called photocytes. The light produced is then emitted through a special part of the insect’s exoskeleton called the cuticle. Since the propagating light travels at different speeds through the cuticle than it does through air, the mismatch causes the light to reflect back dimming the glow.

Misfit scales found on the lantern of the Photuris firefly. (c) Optical Express

Misfit scales found on the lantern of the Photuris firefly. (c) Optics Express

Some fireflies, however, like those belonging to the genus Photuris have specialized scales on their cuticles that look like stacked roof tiles that help tone down internal reflection. The same internal reflection issue is also present in man-made LED bulbs. The researchers were intrigued by this and tried to see if they could improve brightness in LEDs through a similar method employed by the Photuris firefly.

“The most important aspect of this work is that it shows how much we can learn by carefully observing nature,” says Annick Bay, a Ph.D. student at the University of Namur in Belgium who studies natural photonic structures, including beetle scales and butterfly wings.

The researchers used a laser to etch a profile into that coating, similar to that of the edges of the firefly scales, that was applied on a gallium nitride LED. The team remarkably reported an increase in efficiency of 55%, findings which were reported in the journal Optics Express in two papers (1 and 2). Hopefully the technique used might be employed in large manufacturing of LEDs.

“We refer to the edge structures as having a factory roof shape,” says Bay.  “The tips of the scales protrude and have a tilted slope, like a factory roof.” The protrusions repeat approximately every 10 micrometers, with a height of approximately 3 micrometers. “In the beginning we thought smaller nanoscale structures would be most important, but surprisingly in the end we found the structure that was the most effective in improving light extraction was this big-scale structure,” says Bay.

source: Optics Express