Question

What are amino acids? How can amino acids act as a buffer?

Answer 1

The word buffer as we know means a solution that can resist the change in pH upon the addition of an acidic or basic component. They are able to neutralize small amounts of added acid or base, thus helping in maintaining the pH of the solution relatively stable. An example of a buffer is a solution of acetic acid and sodium acetate that consists of a weak acid and its salt.

Complete step-by-step answer: Amino acids are defined as an organic compound that contains amine and carboxyl functional groups, along with a side chain which is specific to each amino acid. The key components of an amino acid are carbon, oxygen, hydrogen, and nitrogen. The general formula of an amino acid is ${H_2}CHR COOH$, where R is a side chain characteristic of each amino acid. Amino acids are said to be building blocks of proteins.

An amino acid can act as a buffer because it can react with added acids as well as to keep the pH nearly constant.
Because an amino acid has both an acidic group which is a carboxyl group and a basic group which is an amine group, hence it can act as both acid and as a base therefore amino acids can act as a buffer.
In very acidic media, the amine group is in the protonated form, and in basic media, the carboxyl group is in the deprotonated form.
At an intermediate pH which is the isoelectric point both ends will be in their ionic form.
An example of this is the protein hemoglobin which can bind to small amounts of acid in the blood thus helping to remove that acid before it can change the blood's pH thus making it an excellent buffer.

Note: Amino acids are the monomers which make up the proteins, each of these amino acids are called a polypeptide. Amino acids are important in a number of ways. They are essential for the synthesis of proteins and also for your enzymes, hormones, neurotransmitters, metabolic pathways, mental stabilization, and just about every function that takes place within the human body.