The effect of thiourea and formaldehyde treatment on the chemical analysis of wool. II. Amino acid analyses

Abstract

The anomalous amino acid analyses obtained for some amino acids, from the hydrolysates of thiourea-formaldehyde and formaldehyde-treated wool samples, are due largely to reactions with formaldehyde during acid hydrolysis. A new technique has been developed, involving hydrolysis in refluxing hydrochlorio acid in an atmosphere of nitrogen. This method improves the recovery of amino acids and has also been of assistance in explaining the abnormal analyses observed for oystine, tyrosine, lysine, and threonine in the presence of formaldehyde.