METHYLTHIOHYDANTOIN AMINO-ACIDS - CHROMATOGRAPHIC-SEPARATION AND COMPARISON TO PHENYLTHIOHYDANTOIN AMINO-ACIDS

Most phenylthiohydantoin (PTH) amino acids and most methylthiohydantoin (MTH) amino acids may be separated from one another by thin-layer chromatography (TLC) using the same sequential development technique with the same two solvents. Similarly, a single solvent system may be used in high-performance liquid chromatography (HPLC) to separate most PTH-amino acids and most MTH-amino acids. When both TLC and HPLC separations are performed on a sample, all MTH- and PTH-amino acids can be uniquely identified. Since many solid-phase protein sequencing techniques generate both MTH- and PTH-amino acids, these analytical systems simplify identification of the amino acid derivatives. Although the chromatographic properties of MTH- and PTH-amino acids are similar, they are not identical (contrary to a previous report). © 1979.