Amino Acid Analysis using Hydrolysis, Ion Exchange Chromatography, and Ninhydrin Detection

Approximately 200 mg freeze-dried material was dissolved in hydrochloric acid solution and phenol was added. The solution was heated at 110 °C in a nitrogen-filled environment for 22 hours. The filtrate was evaporated and then treated with sodium citrate. The proteins were broken down into amino acids, separated by ion exchange, and detected using ninhydrin solution for amino acid content analysis using spectrophotometry.