[Antibody affinity in serological immunosuspension tests].

An original method for the determination of antibody affinity (in SI physical units) with the use of serological immunosuspension tests--the indirect hemagglutination (HA) test and the latex agglutintion (LA) test--was developed. The immunological and physico-chemical properties of suspensions in the indirect HA test and the LA test were linked with the character of the manifestation of test results in the form of "umbrellas" or "buttons" which appeared as the result of the sedimentation of physical carriers. The experimentally determined mass of carriers per unit of volume of the test suspension made it possible to establish bioenergy per unit of volume by the potential energy of carriers forming "umbrellas". Antibody affinity is the force of interaction in one pair of determinants, expressed in newtons and determined by means of the indirect HA test and the LA test. Thus, in antibodies to the causative agent of plague it was, respectively, 1.028x10(-17) and 0.1014x10(-17).