A study was made of the specificity of artificial compound-antigens containing aliphatic chains.
Striking specificity was exhibited in the reactions of compounds with short chains containing a carboxyl group; for instance succinic acid could be differentiated from malonic or glutaric acid which contain one fewer and one more carbon atom respectively. With the substances containing longer chains, reactions were observed which, although specific to a certain extent, appear to depend mainly on the general physicochemical properties of long aliphatic chains.
With a limited number of substances the influence of substituents —halogen, OH, NH2—on the serological specificity was investigated.
By means of inhibition reactions it was possible to demonstrate the serological specificity of cis-trans isomers such as maleic and fumaric acid.