Chemiluminescent determination of tryptophan in a flow injection system

A method is described for the determination of tryptophan in which it reacts with cerium(IV) in 0.15 M sulphuric acid. The method is rapid and precise and solutions can be analysed at a rate of 211 h −1 with a relative standard deviation of ca. 0.45% at 12.5 μg ml−1 and a limit of detection of 0.1 μg ml−1. The effect of some common amino acids and monosaccharides which may be present along with tryptophan in tissue or protein hydrolysates has been investigated.