During Amino Acid Analysis, proteins and peptides are hydrolyzed to their component amino acids which are then separated by HPLC, detected by UV or flourometry and quantitated.
When Amino Acid Analysis is used to measure the free amino acids that are not bound up in a protein or peptide but exist freely in a biological tissue like serum, spinal fluid and cells, hydrolysis is not used. Usually, higher molecular weight proteins and peptides are removed from the matrix by a filter. However, the assay is “blind” to the peptides and proteins and only the free amino acids are derivatized and seen in the working part of the chromatogram.
Amino Acid Analysis can be used to answer many biological questions. New technologies have permitted the assay to be scaled down and allow greater sensitivity and the analysis of less abundant samples which increases the usefulness of this assay greatly.
Amino Acid Analysis is a useful tool in synthetic peptide qualification. The mole percent of each residue can be compared to the expected percents from the known sequence.