In class I've been studying different chemical reactions through a number of different labs. This week we read an article about chemoluminescence, especially in glow sticks. This article relates to my learning because chemoluminescence is a particularly useful and efficient tool in everything ranging from emergency workers to crime scene investigators to medical researchers. It is important to learn about Chemoluminescence because of both the efficient and helpful uses for it that we've already found, as well as the possibly life-saving prospects of what it could be used for in the future.
Because of how important Chemoluminescence is, it's also to understand the words used to describe it. To fully understand the topic, you need to know the terms defined below:
Chemoluminescence: Light emitted by the decaying of an unstable product of a chemical reaction.
Product: A substance formed by a chemical reaction.
Stable: When a system is in it's lowest energy state and isn't going to decay.
Unstable: Liable to decay and to deteriorate.
Emitted: Exuded or produced.
Next, I will discuss the following topics: early uses of chemoluminescence, glow sticks, chemoluminescence in forensics and efficiency, and how chemoluminescence is being used to help diabetics.
All Chemoluminescence reactions create an unstable product that decays, producing light. For example, when the element phosphorus is exposed to damp air, an atom of phosphorus is released and absorbed into the air. This causes the molecules to return to a more stable state, emitting a greenish light while it does so. The light is formed by the atoms being released.
Glow sticks, also known as light sticks, are used by a number of different people, such as emergency workers, military personnel, rave dancers, and Halloween trick-or-treaters. They are generally used when it would be impractical or unsafe to use electricity to generate light. There are two chemicals in glow sticks — usually hydrogen peroxide and cyalume — separated by a glass separator. To 'activate' the glow stick, you 'snap' the separator, allying the two chemicals to mix, causing a chemical reaction. This excites the dye inside the stick, which then causes the stick to glow the color of the dye in the stick.
Chemoluminescence can also be used for forensics by crime scene investigators. One chemical, luminal, is used to detect blood at crime scenes. This is because it reacts on contact with hemogoblin (red blood cells), glowing a greenish-blue color. This means that the investigators can simply sweep the area with luminal, and if it glows greenish-blue anywhere, they've detected blood. Chemoluminescence is also surprisingly efficient compared to our electric lights. For example, a light bulb has 10% efficiency in transferring energy to light, while a firefly has 88% efficiency.
Chemoluminescence can even be used in medical science. Researchers have been recently experimenting with alternatives to what is currently the only way to diabetics' health - constant finger pricks to test glucose levels and inject insulin. What they've come up with utilizes Chemoluminescence, and looks like it may be a much less irritating and safer alternative. Tiny implants can be injected into the skin without surgery, where they monitor glucose levels by immediately reacting and glowing if blood pressure increases. They're estimated to last about 140 days, because that's how long they've lasted in mice before requiring replacement. The implants can be replaced as easily as they're implemented, with no surgery - quickly and fairly painlessly removed with tweezers. It looks like they'll be a safe alternative for humans, as long as they use well-sealed, with safe chemicals in the implants.
Overall, Chemoluminescence is an important and useful concept to understand, with a variety of current and possibly uses, all of which are interesting to learn and write about.
