|Molecular Weight||75.067 g/mol|
Dimethyl sulfoxide is important polar aprotic solvent, which is frequently used in pharmaceutical drug manufacturing, desolution, etc. DMSO is used as one of the solvents on protein chemistry due to universal ability to dissolve small molecules like amino acids. Amino acids and DMSO are very polar and have no retention on reversed-phase columns. In this HPLC application DMSO and glycine are separated on Primesep 100 mixed-mode column. DMSO is retained by weak reversed-phase mechanism and very low organic concentration is required in order to achieve any retention. Glycine, like any other underivatized amino acid, is retained by weak reversed-phase and moderate cation-exchange mechanism. Method uses acetonitrile/water/TFA gradient and UV detection.
Application Notes: Amino acids are polar ionic compounds which are not retained on reversed-phase column without ion-pairing reagent. In our application, lysine and arginine can be separated from other amino acids. Amino acids with a pH between 3 and 5 and with one basic and one acidic group become very polar. Therefore these amino acids don’t have strong ion-exchange interaction with Primesep C stationary phase. Amino acids with two amino groups still carry positive net charge and can interact with stationary phase by cations-exchange mechanism. pH variation of the mobile phase can be an effective tool to adjust selectivity of separation for zwitter-ionic, basic and acidic compounds. This method can be used for separation of mono-charged compounds from compounds having an extra charge.
Application Columns: Primesep C
Application compounds: Aspartic acid, Glutamic acid, Aspargine, Glycine, Proline, Alanine, Phenylalanine, Tyrosine, Leucine, Lysine, Arginine
Detection technique: UV, LC/MS, ELSD/CAD