Hypochlorous acid

This special liquid forms when chlorine meets water. It is a powerful tool for cleaning. It can kill germs on many surfaces. It even works on tiny germs like COVID-19.

Your body uses it too! Tiny cells in your blood make it. These cells use it to fight bad things. It helps keep you safe from germs.

Doctors use it to help heal wounds. It can also be used to clean food. It is even used in swimming pools. It is a very helpful helper in our world.

Hypochlorous acid is a special liquid. It forms when chlorine dissolves in water. It is a strong oxidizer. This means it can change other things it touches. This power helps it kill many tiny germs. It can even destroy germs like COVID-19 on surfaces.

Our bodies use this acid too. White blood cells make it to fight bad things. They use a tiny tool called myeloperoxidase. This tool helps the cells make the acid. It helps them stop germs from hurting us.

People use it for many jobs. It is an ingredient in many bleaches. It can also be used to clean wounds. The FDA says it can help treat infections in humans and pets. It is even used to clean food and water. Some ships use electricity to make it. This cleans waste before it goes into the sea. It can even remove bad smells from trash or toilets. A scientist named Antoine Jérôme Balard found it in 1834.

Hypochlorous acid is a very special substance. It is an inorganic compound with the formula HClO. This acid forms when chlorine dissolves in water. It is a strong oxidizer, which means it can change other things it touches. Because of this, it is a great tool for cleaning. It can destroy many germs, including the virus that causes COVID-19.

This acid works in a very specific way. When it touches tiny germs, it attacks their vital systems. It can react with many different parts of a living thing. It reacts with proteins, which are building blocks for life. It also reacts with DNA, which carries instructions for cells. It can even change fats, called lipids, in a cell's outer layer. This makes it very hard for germs to survive.

We can thank a French chemist for finding this acid. His name was Antoine Jérôme Balard. He lived from 1802 to 1876. In 1834, he discovered it in a lab. He did this by adding mercury(II) oxide to chlorine gas in water. He was also the person who gave the acid its name.

Today, we use hypochlorous acid in many places. It is an ingredient in many types of bleach. The U.S. Food and Drug Administration, or FDA, has approved it for many jobs. It can be used to treat wounds and infections in humans and pets. It is also used as a preservative for saline solutions. Some restaurants use it because it is not flammable and is not toxic.

Nature actually uses this acid all on its own. Your body has white blood cells that fight off bad things. These cells use a tool called the enzyme myeloperoxidase. This enzyme helps the cells make the acid to fight germs. Even ships use a similar idea to stay clean. They use electricity to turn seawater into this acid. This cleans waste before it is released into the ocean.

Hypochlorous acid is a powerful inorganic compound with the chemical formula HClO. It is also known by several other names, such as HOCl, ClHO, or HClO. This substance is a strong oxidizer, meaning it can chemically change other molecules through oxidation. This property makes it a primary disinfection agent in many chlorine solutions. It is highly effective at destroying pathogens, including the virus that causes COVID-19.

The formation of hypochlorous acid follows a specific chemical process. When chlorine gas is dissolved in water, it reacts to produce both hydrochloric acid (HCl) and hypochlorous acid (HClO). In an aqueous solution, the acid also partially dissociates. This means it breaks apart into a hypochlorite anion, which is written as ClO-. Because of this constant shifting, HClO cannot be easily isolated from these solutions. It stays in a state of rapid equilibrium with its precursor, chlorine.

This acid works by attacking many different parts of a living cell. One major target is proteins, specifically those containing sulfhydryl groups. When HClO reacts with these groups, it causes them to form disulfide bonds. This process can lead to the cross-linking and aggregation of proteins. It can also react with the amino groups in amino acids. This reaction forms organic chloramines, which can eventually cause the protein to fragment or break apart.

Hypochlorous acid also interacts with the genetic material of microbes. It reacts with DNA and RNA, as well as all nucleotides. The most reactive nucleotide is GMP, followed by TMP. These reactions can interfere with how DNA bases pair together. This interference is similar to the effects seen during heat denaturation. While the acid reacts with the nitrogenous bases, the sugar moieties and the DNA backbone remain unreactive.

Another target for the acid is the lipid layer that surrounds cells. Hypochlorous acid reacts with unsaturated bonds in lipids through a process called hydrolysis. This adds chlorine to one carbon and a hydroxyl group to another. The resulting compound is known as a chlorohydrin. These polar molecules can disrupt lipid bilayers, which are the protective layers of cells. In red blood cells, this can increase the permeability of the cell membrane.

The history of this compound began in 1834. A French chemist named Antoine Jérôme Balard discovered it. He conducted his experiment by adding a dilute suspension of mercury(II) oxide to a flask of chlorine gas. Balard was also the person who named the acid. He chose the name "hypochlorous" because it reflected its similarity to other substances like hyposulfurous acid.

Today, the applications for hypochlorous acid are quite broad. In medicine, the U.S. Food and Drug Administration has approved it for treating wounds and infections in humans and pets. It is also used as a preservative for saline solutions. In the food industry, it is used to treat food preparation surfaces and water supplies. It is popular in restaurants because it is non-flammable and nontoxic.

Nature and technology both utilize this chemistry in interesting ways. Mammals use hypochlorous acid as a tool in their white blood cells. Specifically, an enzyme called myeloperoxidase (MPO) helps generate the acid to fight foreign bodies. Even marine sanitation devices on ships use electricity to convert seawater into hypochlorous acid. This process disinfects waste before it is discharged into the sea. In water treatment, it remains the active sanitizer in many hypochlorite-based products used in swimming pools.