This lesson discusses something known as plasma as well as hydrogen peroxide gas plasma, ions, electrons, and more. We'll talk about how gas plasma is used for sterilization and what it kills.
The Four States of Matter
Life is made up of different states of matter, meaning we have solids, such as rocks, that help to make up our planet. Our world is also full of liquids that sustain life, such as water. Finally, gases are super important as well, especially the air we breathe. Gases, solids, and liquids are the three states of matter that I'm positive you have heard of. However, there's one more, a fourth state of matter, which is commonly missed by most people.
What Is Plasma?
This state of matter is known as plasma, which in the context of this lesson is a gas-like substance consisting of particles such as positive ions and electrons. Note how this term isn't referencing the plasma membranes cells have or blood plasma. It's something else altogether. It's actually sort of cooler in a way.
The details of the differences between plasma and the other three states of matter are best left for a physics lesson. However, I'll go over the basic concepts necessary to understand how plasma works in the context of sterilization. As I intimated before, plasma is a collection of things like ions and electrons. Don't be confused by those terms, as I'll briefly go over them.
I'm sure you know that the atom is the basic unit of matter. Atoms combine to form larger structures, called molecules, which in turn combine to form even larger structures, like a human being. To put it another way, an atom is a letter in the alphabet, a word made of up of several letters is a molecule, and an entire book written using words is akin to a human being. Each atom - each letter that is - is made up of different parts as well.
For example, the small letter 'i' has a vertical line and a dot at the top. Likewise, atoms are made up of smaller, or subatomic, particles called electrons, protons, and neutrons. If an atom has an equal number of protons, which are positively charged, and electrons, which are negatively charged, it's considered to be a neutral atom. However, if it has more protons than electrons, or vice versa, it becomes positively or negatively charged, respectively. An atom with a positive or negative charge is known as an ion.
Gas, Plasma, and Sterilization
Now that we've got that little physics tidbit out of the way, it will be easier to understand how something called hydrogen peroxide gas plasma, a type of substance used for sterilization, actually works. First, hydrogen peroxide, a type of highly reactive compound, is added to a chamber, where it is vaporized into a gaseous state. Once the gaseous state of hydrogen peroxide is achieved, an electrical field is applied to it. This electrical field causes the gas to ionize, meaning, just as I described before, ions and electrons are generated, and we form something that is called gas plasma. In the course of creating this plasma, something known as a free radical is formed.
If I was a betting man, then I would guess that you have heard of free radicals before. You've probably read about how the sun causes your skin to be damaged by free radicals, or how you should take vitamin C or vitamin E to help prevent free radical damage to your body, and so on. The reason free radicals are so dangerous is because these are particles that basically react with anything that comes in their way and end up destroying it.
To illustrate, you can think of a free radical as a really hot flame from a super-charged blowtorch. It doesn't matter if the hot flame is briefly touched to something easily destroyed, like paper, or to something tough, like a brick. Given enough time and exposure to the flame, the flame will end up cracking and destroying even the hardiest substances. Likewise, given enough free radical damage, cell walls, nucleic acids, and so forth can be destroyed in a cell. This type of damage may even lead to cancer.
However, when used in the context of gas plasma sterilization, these free radicals become our best friends, as they destroy bacteria, viruses, fungi, and dangerous bacterial spores, much like a really hot flame from a blowtorch would as well. The great thing about gas plasma is that it's non-toxic compared to other methods of sterilization. Gas plasma can also sterilize very quickly and can be applied to virtually any, especially heat-sensitive, material that needs to be sterilized.
While this was more of a physics lesson, do recall that hydrogen peroxide gas plasma, a type of substance used for sterilization, kills bacteria, viruses, fungi, and even bacterial spores. Therefore, it has quite a lot of applications when it comes down to keeping inanimate objects, such as medical devices, free from living microbes.
The state of matter generated by electrically charging hydrogen peroxide vapor is known in general as plasma, which in the context of this lesson is a gas-like substance consisting of particles such as positive ions and electrons.
An atom with a positive or negative charge is known as an ion. However, besides ions and electrons, free radicals are generated when hydrogen peroxide gas plasma is made. These free radicals react with virtually any structure that makes up a microbe, destroying the microbe in the process.
After this lesson is finished, you should be able to:
- Explain the physics of plasma
- Define hydrogen peroxide gas plasma
- Describe the sterilization process involving hydrogen peroxide gas plasma