Elastic light scattering on reagent mixture in the immune reaction process in vitro

The paper is devoted to computer simulation of elastic light scattering on reagent mixture during the immune reaction process in vitro. The immune reaction was analysed in the limits of the 3-stages process of antigen-antibody complexes aggregation. Antibodies were treated as bivalent biomolecules, antigens were performed by 2, 3-valent biomolecul or polyvalent cells. Two variants of the problem solution of light scattering on the biological objects chosen were analysed Rayleigh-Gans theory, the approach [1], and Mie theory [2], the preference was given to the first one. The optimum of the immune reaction output was revealed at quite a definite ratio of initial reagents concentrations. This optimum is an analog of experimentally a well known phenomenon - the "zone of equivalence". It's shown that the form of the "zone of equivalence" both depends upon the kind of experimental procedure and the ratio of the antigen, antibody sizes. This result is preferably to take into consideration while one tries to optimize the medical diagnostic procedure based on the immune approach. It was revealed that the scattered light power correlates with the immunochemical kinetics not adequately sometimes. That fact may be useful to interpret the experimental investigations and at the same time it may give a principal possibility to use nephelometry for the aims of immune metrology.