I’ve seen Hydrogen Peroxide as an ingredient in a lot of disinfectants, but I’m not well-versed in chemistry, so I was trying to get a better idea of how it works. I keep reading something about the extra oxygen, but if that could be Eli5-ed, that’d be great.
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The extra oxygen in H202 has fewer electrons that it wants to have. Joining with water to form H202 is *ok* for it, but it would much rather just have enough electrons.
So when the H202 touches another material it’ll rip away electrons, give them to the oxygen, and the oxygen is happy and leaves the H202. Two such Oxygen atoms will form a pair called, O2 or “molecular Oxygen” which is just normal Oxygen gas. So that’s why the peroxide bubbles and produces a gas, leaving behind water.
But the material that had it’s electrons stolen is now “broken”. In the case of this material being the cell wall or membrane of a living thing, this usually results in the death of the cell.
Hydrogen Peroxide is H2O2 and it is unstable, it readily breaks down into just plain water H20 and O. Nascent oxygen, is fiercely reactive *something* is going to get oxidized, living things do do well in such conditions.
Peroxide reacts with human blood, the bubbles are nascent oxygen. Peroxide can be used to clean up a minor blood spill on a white lab coat. The reaction smells like burnt hair or feathers.
A big portion of why H2O2 works as a disinfectants is because we consider it a part of the ROS family. ROS stands for “Reactive Oxygen Species”, with chemicals such as OH-, O2(-), O2(2-) etc being other members of the ROS family. These are basically chemicals which have extra oxygen atoms which give it their disinfectant properties.
ROS are normally present in cells is small concentrations. Think of them as toxic wasteful byproducts of metabolism. That’s why cells have organelles called peroxisomes which act as cell cleaners for this type of waste. Peroxysomes have many enzymes suitable for breaking down ROS, the most notable one is catalase. It speeds up tthe breakdown of H2O2 into H2O and O2, which are less harmulf than H2O2. If a cell is working overtime, and has no adequate antioxidant support, it produces a lot of ROS that overwhelm the peroxysomes. Peroxysomes can’t keep up with excess ROS production and the cell enters a state called “oxidative stress”
Oxidative stress can cause a myriad of disfunctions of a cell. It can damage basically any cell structure and component, from its cell wall, proteins, lipids, DNA, etc. Because ROS have that extra Oxygen, they became *very* reactive. This makes them meddle in other cell molecules, changing them. For example, polyunsaturated lypids which can be found in the cell wall, can be changed by the ROS which makes them lose their function and destabilize the membrane. Proteins also get modified by ROS, which can change their structure and shape and, therefore, their function. DNA can also get damaged by the ROS which causes mutatuion which is almost always a bad thing. This is the Eli5 answer to your question.
As you can see, ROS, and therefore H2O2, are bad for a cell. In a similar way, they are bad for bacteria. They destabilize their membrane, making it suceptible to damage and death. That’s why H2O2 can be used as a disinfectant.
If you have further questions, or want a deeper delve into the chemistry, feel free to ask.
H2O2 wants to be water (H2O) but it’s got an extra oxygen. The extra oxygen wants to attach to something else so badly that it rips into the cell walls of microbes, essentially burning them do death. Hydrogen peroxide is powerful stuff, try not to use it on your skin.
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