Of all the fields in science, medicine, as it is practiced in labs, might be the most jargon-laden. Doctors have a thousand names for a thousand things, of course, and it is highly warranted given the incredibly complex nature of the human body. No system though, even among the labs, is more complex than that of the immune system. How our body adapts to the threats it faces can be confusing and intricate in equal measure, so it’s no surprise immunochemistry is an intimidating subject.
Immunochemistry is an immensely important subject though since our body is in many ways a system of chemical reactions that works within itself. If you have a disease and your system is working poorly it can be extremely difficult to tell what is going on, but tests developed by immunochemists can help with that by searching for antibodies and other similarly complex molecules. So, let’s break apart a bit of this specialization, with the ultimate goal of learning what a diluent is and why everyone needs to care about it.
What’s the Problem Diluents Address?
Before we get to the issue of what these substances are, we need to address first the problems that preceded their development. An immunoassay is a test, plain and simple, for a specific substance in a sample. Depending on the disease, the molecule a test is looking for can vary, but for instance, if the disease has a prevalent marker in a red blood cell, an immunoassay normally (simplifying a lot here) injects an antibody into the sample. The cell competes with the antibody for proteins that are markers of the disease. We can then measure the effect and using our knowledge of the body determine if that sample has that disease.
So this is the basic premise of this type of test, and for the most part the way chemical bonds work this competition is very effective. But, we need to add an extra layer of complication here, so before moving on click here for a summary of the immunoassay and its specifics.
Chemical bonds are mostly random fundamentally. The bonding of atoms because of missing electrons is one of the parts of chemistry that makes our universe run. But, if these building blocks can be stopped before forming, it would make the immunoassay an ineffective test. False positives may form if the antibodies injected are bonded with another substance, or a false negative if molecules bond with the thing you’re trying to test for.
This is a common occurrence in nature but for a lab test, we need to be able to determine or avoid these kinds of issues. So, in steps a diluent, which is effectively something that (surprise) dilutes a substance. For those uninitiated in chemistry, imagine watering down a beverage.
This is the basic process of dilution in action, making the substance less concentrated by adding more inert junk. Water is usually the go-to for this, distilled of course to avoid the chemicals that are present in tap water, although alcohols and oils can serve similar purposes.
Why is Dilution Important?
Dilution is important for the tests labs perform on a daily basis because it spaces apart molecules to lessen the likelihood that they bond with an antibody the test wants to avoid. These antibodies are annoying for scientists and often unless near physiological pH is maintained these chemical bonds can form due to the chemical disturbance of becoming more acidic or basic.
Don’t let the fancy terms make your head swirl though, a diluent’s primary purpose is for dilution for storage and transfer. If you want more specifics, try this paper: Diluent Buffer Ions and pH: Their Influence on the Performance of Monoclonal Antibodies in Immunohistochemistry though journal articles concerning immunochemistry don’t mess around.
The Cool Parts of Dilution
Substances that need dilution are absurdly specific in their nature. If you want to test blood, diluting with just anything won’t work. Specialty diluents can mock the specific makeup of a substance, including viscosity, pH, and even chemical composition. Chemical composition is possible the most impressive part since the decomposition of things into their component parts is a natural law of the universe
If you want the chemistry nerd taken out of dilution, it becomes a lot less interesting. But, part of the joy of language is that with every jargon-laden essay or article there is potential for conversation. If you end up dismissing each term you end up losing the passion that a lot of people have for a lot of these processes. Learn to pick apart terms into the component parts, so that even if the language of a conversation is diluted with buzzwords, you can work past it to bond closer with the people who do important, meaningful work every day.
