Acids and bases, many have heard of them since they were young. Dangerous is a word that usually coincides with these as well. Little do people know that they are extremely important in everything us humans do. Buffers have the ability of “neutralizing both acids and bases and thereby maintaining the original acidity or basicity of the solution” as Websters dictionary states. In other words, buffers have the ability of staying their original pH even if an acid or base is added; Some common examples of buffers are Acetic Acid and Sodium Acetate. Why does this matter many might ask; well, it matters immensely for how our body functions. Everyone knows blood circulates in our body and allows us to get oxygen, but without buffers that would not be possible. To explain buffers, we will discuss their criteria, their equilibrium shifts, and how the buffers work in blood.
First, we must start at the basics. What makes a buffer a buffer? A buffer consists of a weak base or acid with its conjugate. Promega, in the Buffers for Biochemical Reactions article gives a list of what is considered a good buffer. On this list it includes, “A pKa between 6 and 8”, “Solubility in water”, “Minimal salt effects”, and “Chemical stability”. The main important factor would be that it maintains its Hydrogen ion concentration well. The hydrogen ion is what determines the pH; the higher the Hydrogen ion concentration the more acidic the solution. It is important to remember that a buffer is only possible if a weak acid or base is added to the buffer solution. When this happens there will still be a minuet change in the pH but it will be a lot more minimal than if there was no buffer.
Next, we will discuss the equilibrium shifts and how they work. The principle to equilibrium shifts is called Le Chatelier’s principle. This principle clearly states how equilibrium is affected from reactions. The biggest thing to remember, as claimed from Canada’s first edition of Introductory Chem. with this principle is that when stress is added to the reaction, the equilibrium shifts to reduce the stress. In other words, if something is added to one side of the reaction is will usually shift in the other direction to alleviate the stress. This is the same case as if something was removed from either side. An example of this would be if you oversaw a lemonade stand. You had ten lemons that could make 5 cups of lemonade. If two people buy lemonade (products removed), then you have to shift towards the products to make more. The same would be if you were given a bunch more lemons, you would make more lemonade because you have an excess on the “reactants” side. This is how it works with a reaction. Another easy way to remember is by using the “U-Tube” which is where you basically just draw a “U” that has equal amount of water or whatever you want it to be. If you remove some from the left, it will naturally fill up that side because water flows where there is least resistance.
Now that you understand better how buffers work, I will talk about body buffers, specifically in blood. Human blood sits around 7.35-7.45 pH. It is important that it stays between that narrow margin or it could be fatal for the individual. Luckily, we have multiple buffers to help us out. This includes the Protein Buffer system, Phosphate Buffer System, and Bicarbonate buffer system. The Protein Buffer system focuses on hemoglobin, as Healthfully article states, “Hb is the protein that functions to transport oxygen within the body.” Phosphate Buffer System helps keep the H+ ions in check by accepting them if there gets too many. This allows the H+ and OH- ions to stay in equilibrium with each other. The Bicarbonate Buffer System aids in the pH in our stomach and intestines; it “manages the release of excess carbon dioxide as a bi-product of cellular respiration” as Healthfully’s article discusses. Clearly, all these buffers are extremely important in our bodies to help them function correctly.
In conclusion, buffers help our world immensely. Not just scientists doing experiments, but they play a role in our everyday lives inside us, friends, family, pets, etc. None of it would be possible without buffers to help us function how we are supposed to. Next time you hear the words acid or base you can remember just how well our body does to protect us from these and how they are not always dangerous.
