A comparison of the Farr technique with equilibrium dialysis for measurement of antibody concentration and affinity.

The Farr technique has been compared with equilibrium dialysis in regard to its ability to measure antibody concentration and affinity. An excellent qualitative agreement between the two techniques was obtained. Quantitatively, the Farr technique tended to underestimate antibody concentration and overestimate antibody affinity. It is likely that these observations are due to the failure of some low affinity antibodies to bind hapten under the conditions of the Farr assay.