SRM 2389a consists of 17 amino acids in 0.1M HCl at nearly equimolar concentrations. This SRM will serve as a replacement for SRM 2389, which was certified using a combination of data from NIST and collaborating laboratories. The NIST data was based primarily upon LC-UV measurements of derivatized amino acids. Since that time, a set of isotope-dilution liquid chromatography-tandem mass spectrometry (ID LC-MS/MS) methods have been developed for absolute quantification of each amino acid. Value assignment of SRM 2389a represents the first time that NIST has quantified all 17 of these amino acids by isotope-dilution LC-MS/MS methodology. Certified values for SRM 2389a will be assigned as a combination of the isotope dilution results with the gravimetric data associated with the production of the SRM solution. The LC-MS/MS methodology developed for this work can also be applied to measurement of amino acids in other matrices.
- A Standard Reference Material for amino acids in solution has been developed and certification measurements have been completed for all 17 amino acids.
- Isotope-dilution LC-MS/MS methodology has been implemented for quantification of amino acids.