The Chemistry of Quats

I would imagine that people – perhaps even you – who use disinfectants hear the word “quats” quite frequently. But do you know what quats are?

“Quats” is short for quaternary ammonium compounds, which are similar to ammonium ions in structure. Just instead of being 4 hydrogens surrounding 1 nitrogen, they have 4 R groups. Now these R groups can be many different things, but still be a quaternary ammonium compound. They can either be an alkyl group, which is a chain of carbons and hydrogens or they can be an aryl group, which is a ring of carbons and hydrogens. These chains and rings can also contain other molecules, such as oxygen.

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Different quats have different functions because of the variety of R groups that they can have. The different combinations of rings, chains, carbons, hydrogens, and other elements give each quat its own functionality. This is why there are so many quats that are used in cleaners and disinfectants. Quats tend to have antimicrobial properties, making them valuable as disinfectants. They work in a variety of ways to disrupt cell membranes, inactivate energy-producing enzymes, or denature essential proteins in the microbes, effectively killing them.

The problem is that quats also have the potential to add to the growing number of resistant bacteria and they make poor cleaners. When a quat-based disinfectant is used to clean, some of the quats get left behind on the surface as a residue. This residue builds up on the surface, causing it to look dull and grimy. Over time this accumulated grime will make the surface look dirty even after being cleaned and it will attract even more dirt to it! So the various microbes may be dead, but the surface will look dirty, and who wants that?

Lastly, if you ever wonder about the really long names that quats have, it is just a way for chemists to remember the structure of the molecule. By breaking down the name, they can easily draw out the molecule’s structure and from that know how it will behave!

If you find this information useful and want to know more, let us know in the comments!