Conjugates of benzidine with a ternary phenol-containing copolymer of N-vinylpyrrolidone as test antigens for the detection of benzidine in human serum.

Water-soluble polymeric amide and azo derivatives of benzidine, based on the terpolymer N-vinylpyrrolidone-crotonic acid-p-crotonoylaminophenol, which possesses adjuvant activity, were synthesized. By means of a double diffusion reaction in agar and a complement-binding reaction it was found that immunization of rabbits with the benzidine-polymer antigens (with or without complete Freund's adjuvant) led to the formation of highly specific antibodies against the hapten benzidine. Sera from rabbits immunized with these conjugates of benzidine may thus be used for the detection of benzidine in the sera of workers exposed to this chemical.