A Universal HPLC-MS Method to Determine the Stereochemistry of Common and Unusual Amino Acids

The determination of the stereochemistry of common and unusual amino acids is important in food chemistry, archeology, medicine, and life sciences, including such diverse areas as marine biology and extraterrestrial chemistry and has greatly contributed to our current knowledge in these fields. To determine the stereochemistry of amino acids, many chromatographic methods have been developed and refined over the last decades. Here, we describe a state-of-the-art indirect chromatography-based LC-MS method. Diastereomers were formed from amino acids that were reacted with chiral derivatizing agents, such as Marfey's reagent (FDAA), GITC, S-NIFE, and OPA-IBLC and separated on a reversed phase column using mass spectrometry compatible buffers.