Gin and Tonic and Malaria and Fluoresence


At the age of 17, George Washington was diagnosed with malaria. The disease, then referred to as the “ague”, came and went over the years. Although it was known at the time that quinine was a successful treatment, Washington wasn’t prescribe the powder until after the revolutionary War had ended and he was in his 50’s. Once he started on the medication, he took such heavy doses that he suffered a drastic and permanent hearing loss. He was nearly deaf by the end of his second term as president.

Quinine is made from the bark of the Cinchona tree, the national tree of Peru, and was named after the Second Countess of Chinchon by Charles Linnaeus. The Quechua originally discovered the medicinal qualities of the bark, using it to reduce fevers and relax tired muscles. The Spanish, who colonized Peru, recognized the importance of the tree as both a medicine and a way to make money. In the early 1800’s they made export of seeds and saplings illegal, thereby monopolizing the market. About a 100 years later, someone smuggled out some seeds and started a Cinchona plantation in India. Perhaps you’ve heard of Bombay Gin?

Today quinine is still used to prevent and treat malaria, but many people opt out of the pills for a tastier prevention: a gin and tonic. Tonic water contains that very same quinine from the Cinchona tree and so you might see it being sipped where malaria is a common concern.




Besides malaria prevention, quinine has another trick. It fluoresces under ultraviolet light. Things glow because photons are emitted when “excited” (at a higher energy state) electrons drop back to a lower, more stable state. When the UV light shines on the tonic water, the photons given off are of lower energy than the ultraviolet light and correspond to blue light in the visible spectrum.


What to know more about George Washington? Come visit Amending America: The Bill of Rights at HMNS. You can also read about one of his more interesting and peculiar contemporaries here.

Want to know more about things that glow? Read Carolyn’s blog or have a gin and tonic. Meet us at the Okra Charity Saloon on Monday September 26th from 5 to 7pm where we will have some science to share!

Glow on, get happy! Join HMNS this Friday for a fun-filled night of light at LaB 5555: GLOW

Whether they’re toys that shine in the night, black lights, glow sticks or fireflies, things that produce an eerie glow are fascinating. Give a kid a glow-in-the-dark toy or paper her ceiling in dimly shining plastic stars, and she will be occupied forever. She’ll find ever brighter lights to charge them up, ever darker places to view them for maximum glow effect, and generally love exploring how it all works.

You know this; you were that kid. So what’s the deal with the glow?

Enjoy a sip of the galaxy -- learn how to make this glow-in-the-dark cocktail at Neatorama

Learn how to make this amazing looking glow-in-the-dark cocktail over at Neatorama

It’s 10 p.m. Do you know where your electrons are?

While there are several “flavors” of things that glow, they all have something in common: Things glow because photons are emitted when “excited” (at a higher energy state) electrons drop back to a lower, more stable state. Aside from promising them a pony or a tour of CERN, there are several ways to get your electrons excited.

In chemical glow sticks, a chemical reaction excites the electrons. This process is called chemiluminescence. Glow sticks are an excellent way to experiment with reaction rates and temperature. If you want the reaction to last longer, follow a kid’s advice and put the glow stick in the freezer or in ice water so the reaction slows down; it’ll take longer to use up the chemicals in the glow stick. The trade-off is that because the production of photons is also slower, a cold glow stick is dimmer than a warm one.

Fluorescence is like light recycling. Fluorescent rocks, laundry detergent additives, paint, and even some animals can re-emit light after something shines on them. Usually we’re talking about things getting hit with ultraviolet or ‘black’ light and re-emitting within the visible spectrum. This makes sense because as you progress along the spectrum of electromagnetic radiation, visible light is a bit lower in energy than ultraviolet light — you can’t expose something to lower energy red light and get it to fluoresce in UV, for example. Fluorescent things certainly fluoresce in daylight, but not enough to outshine the ambient light, so they’re most noticeable under a black light in an otherwise dark space.

Phosphorescence is a lot like fluorescence but stretched out over time — a slow glow. So you can shine light (visible or UV) on a glow-in-the-dark star and it re-emits light, too, but over a lot more time, so the glow continues for minutes or hours before it completely dies out. If you have a glow-in-the-dark toy or T-shirt, try “charging it up” with lights of different colors or intensities and checking out the glow that results.

Nature glows

Fireflies produce and use their own chemicals, luciferin and luciferase, to dazzle and attract potential mates — and sometimes to lure prey. A surprising number of marine critters are bioluminescent, too, like dinoflagellates (plankton) that glow when disturbed, the angler fish, and some squid (perhaps they are blending in with starlight from above). Headlines occasionally announce a new genetically engineered “glowing” kitten, rabbit, plant, sheep, etc., but they are almost always talking about fluorescence instead of bioluminescence, so the light is only seen when the animal is placed under ultraviolet light. (One useful application of this is the ability to track a protein related to a certain disease by getting the introduced gene for Green Fluorescent Protein (GFP) to link to the gene for the protein of interest). Some animals like scorpions and jellyfish (the original source of GFP) fluoresce naturally.

Cheap thrills

Sugar and adhesives can exhibit triboluminescence, in which friction or fracturing produces the light. This one is great to try out at home; you just need Wint-O-Green Lifesavers®, transparent tape and a very dark room (a buddy or a room with a mirror is helpful for the Lifesavers portion). Dr. Sweeting (that’s her real name) has more detailed instructions and explanation, but the big idea is that a tiny, but visible, amount of light is emitted when you peel tape off the roll and when you bite into the candy, crushing sugar crystals against each other. The wintergreen oil even improves the effect by fluorescing!

Are there any other kinds of luminescence? Yes! Incandescence, piezoluminescence, radioluminescence, etc. But that’s enough fun for one post. Go try out triboluminescence!

Just can’t get enough? Make sure to come early for the educational portion of HMNS’ LaB 5555 this Friday for more GLOW fun, and learn all about the science of what gives things light. I’ll be there doing demos to light up your night. For tickets and more info, click here!