Synthesis and properties of some gelatin derivatives with substituents at the amino group

Abstract Gelatin has been interacted with benzenesulphonyl chloride and with other sulphonyl chlorides to give sulphonyl‐gelatin derivatives. With dichloro‐s‐triazines, gelatin afforded crosslinked products or monofunctionally substituted soluble products according to the reactivity of the dichloro‐s‐triazine selected and the reaction conditions used; some of the monofunctionally substituted soluble products were reactive towards amines, including gelatin. The properties of the modified gelatins are recorded. Introduction of a sufficient number of hydrophobic groups into gelatin and other soluble proteins conferred diminished solubility in the region of the iso‐ionic point of the derivative, bringing about the separation of a distinct protein‐rich phase (coacervate) from aqueous solution when the pH was adjusted to that region. Some uses of these derivatives are indicated.