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Lugol's iodine

life science Maturity 7-9 Next article →

Lugol's iodine is a very useful liquid. It is also called aqueous iodine or strong iodine solution. This liquid is a mix of two things. It has one part elemental iodine and two parts potassium iodide in water.

This special mix is helpful in many ways. It is used as a medicine and a disinfectant. The World Health Organization even puts it on a list of essential medicines. This means it is a very important tool for health around the world.

There are many ways this liquid works. When doctors use it to check for cancer, they look for starch-like things called glycogen. Normal tissue turns brown when the liquid touches it. However, cells that might be cancer stay pale. This is called a Schiller's test.

In science labs, the liquid acts as an indicator. It turns dark blue or black when it touches starch. This happens because the iodine interacts with the shape of the starch.

It can also help scientists see cell nuclei more clearly. It even helps people study how cells move things through their membranes.

A French doctor named Jean Lugol first made this solution in 1829.

It has a long history of helping people. For example, it was used in the Polish People's Republic after the Chernobyl disaster. At that time, the government used it to help protect people from radiation.

It is also used in the marine aquarium industry. People use it to help reef inhabitants like corals. It can help corals stay bright and prevent them from bleaching. It can even help certain corals grow more polyps.

There are many different strengths of this liquid. You can find it in 1%, 2%, 5%, or 10% concentrations.

In the United States, there are rules for the stronger versions. Any solution with more than 2.2% elemental iodine is regulated by the DEA. This is because the liquid could be used to make illegal drugs.

In the United Kingdom, the NHS paid about £9.57 for 500 ml in 2015. Using the wrong amount can be dangerous. For instance, undiluted 5% solution can hurt the lining of the stomach.

You might see this liquid used in many places you already know. It can be used as a disinfectant for small wounds, like a needle stick.

It can even be used to clean drinking water during an emergency. If you have a home aquarium, you might see it used for sea life. It helps corals get the iodine they need to stay healthy.

Whether in a hospital, a lab, or a fish tank, this liquid is a very handy tool.

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