By Nicole Gadda
Anaerobic? What does that mean?
The word anaerobic means “living, acting, or existing in the absence of oxygen.” The anaerobic chamber, by definition, is an enclosed environment that has no oxygen inside. Typically, it’s made up of 95% nitrogen and 5% hydrogen – an atmosphere humans can’t survive in, but one that plenty of microbes and oxygen-sensitive compounds thrive in!
Fun rating: 5/5
With high difficulty comes high reward. Working in the anaerobic chamber takes a bit of practice to get used to, but once you feel comfortable working inside, it’s super cool to be able to work with samples that can’t be exposed to the oxygen. Technology is amazing, and that’s why I rate working in the anaerobic chamber a full 5/5 on the Fun Scale.
Difficulty rating: 3/5
Doing science experiments in an anaerobic chamber gets a 3/5 rating on the Difficulty Scale. Because we can’t breath without oxygen, scientists can’t physically survive in anaerobic environments. Therefore, we use gloves to access samples inside the chamber from the outside (see picture below). These gloves feel awkward at first, but working with them quickly becomes second nature.
Why do we use it?
There are many reasons why scientists need anaerobic chambers. These units allow us to easily culture and examine samples that can’t be exposed to atmospheric oxygen. Labs that work with oxygen-sensitive compounds or anaerobic microbes need these chambers to work with samples and conduct their research.
You might be wondering how common microbes that survive in oxygen-free environments are, considering we live on a planet that provides oxygen to support life. Well, anaerobic bacteria and archaea are widespread on Earth – existing everywhere that has low or no oxygen. For example, microbes that live in the human gut or in the bottom of the ocean don’t have access to oxygen, and therefore have adapted to survive in anaerobic environments. In order to study these organisms, scientists must keep them inside oxygen-free environments and the anaerobic chamber provides a place to do that.
How does it work? (All bolded terms here are identified in the picture below)
Anaerobic chambers operate by maintaining an environment made up of a gas mix of 95% nitrogen and 5% hydrogen. Gas tanks outside the chamber maintain a continuous supply of these gases. Anaerobic chambers contain a fan box and catalyst trays, which circulate air and remove trace amounts of oxygen by combining any oxygen found within the chamber with hydrogen gas to create water. The dehumidifer removes any extra water created by this process, which maintains an oxygen-free environment. Scientists can bring samples inside the chamber through the airlock. The airlock has two seals that provide access to the inside of the chamber and the outside. When a sample needs to go inside, it is placed inside the airlock and sealed shut before running. When the airlock runs, it removes oxygen from inside the airlock as it releases a gaseous mix of nitrogen and hydrogen to match the anaerobic environment of the inside of the chamber. Once the run completes, the user can open the lock that connects to the inside of the chamber and bring their samples inside to work with. To actually access their samples, scientists use gloves that are built into the plastic exterior of the chamber. These gloves allow them to easily work inside the chamber with only a simple piece of plastic between the scientist and the sample they’re working with.
All images including scale bars created by author.
