Estimation of hydroxyproline by the AutoAnalyser

Abstract

A method has been developed for the determination of hydroxyproline by the Technicon AutoAnalyserl using a modified version of the Stegemann assay (1958). This involves oxidation of the hydroxyproline with chlor- amine T; excess chloramine T is destroyed with per- chloric acid and the hydroxyproline chromogen is then reacted with p-dimethylaminobenzaldehyde to develop a pink colour. In the present method the absorption is measured at 550 my. The reagents used are adapted from the method described by Woessner (1961), in particular the composition of the p-dimethylaminobenzaldehyde solution (P.D.A. reagent) has been changed to avoid precipitation in the transmission tubing. This method has been applied to the determination of collagen and elastin in arteries and connective tissues and the results obtained agree well with those found using a manual method.