A modified ELISA technique for anti-hapten antibodies.

Polystyrene tubes pretreated with glutaraldehyde in phosphate buffer were used in a solid-phase enzyme-linked immunoassary (ELISA). The hapten o-dinitrocarboxyphenol (o-DNCP) was used as coat. The binding of homologous rabbit antibodies was measured with phosphatase-labelled staphylococcal protein A (SPA-PH). This method is both very sensitive (serum dilutions greater than 2 x 10(-6) were still positive) and highly reproducible. Anti-DNP rat IgE was detected with o-DNCP hapten as a coat using avidin/biotin as a marker.