Gas chromatographic separation of protein amino acids in four minutes

A method is presented for analysis of protein amino acids in five minutes, including derivatization. The chemical treatment involves reaction with ethyl chloroformate: if the composition of the reaction medium is optimum this reagent esterifies carboxylic groups simultaneously with derivatization of other reactive groups and the reaction is complete in seconds. The moderately polar silicone OV‐1701 was found to be a convenient liquid phase for separation of the derivatives: a five meter capillary column of internal diameter suitable for routine use was able to separate the amino acids in four minutes. Derivatization of arginine was incomplete and it failed to elute from the column.