Inactivation of Prolactin by Treatment with Phenyl Isocyanate

Abstract

PHENYL ureido derivatives of serum albumin peptone¹, plastein², and native proteins³, have been prepared by treatment with phenyl isocyanate. This reaction is eminently suitable for masking the free amino groups of protein molecules without doing further damage, since the reaction conditions are very mild (0° C. and pH 8). Hopkins and Wormall³ concluded that phenyl isocyanate reacts only with the free amino groups of the lysine components of the protein molecules.