Cereal Chem 45:432 - 436.  |  VIEW ARTICLE
Determination of Lysine on the Automated Amino Acid Analyzer by a Triplicate-Sample Method.

E. Villegas, C. E. McDonald, and K. A. Gilles. Copyright 1968 by the American Association of Cereal Chemists, Inc. 

A triplicate-sample method was developed for determination of lysine by ion-exchange chromatography on an automated amino acid analyzer. In this method, three samples of cereal hydrolysate are applied to the short column of the analyzer, and then the lysine from each sample is resolved with pH 5.10 sodium citrate buffer (0.20M in Na) and recorded as a group of three lysine peaks. The resin is next regenerated with 0.2N sodium hydroxide and then equilibrated with citrate buffer for the next triplicate analysis. Accuracy of the lysine analysis by the triplicate-sample method is good. The number of lysine analyses that could be run per day is estimated to be 15 with one column fitted to the analyzer, 24 with two columns, and 36 with three columns. The triplicate-sample method has been used for lysine determination of numerous samples of several cereals.