Diffusion of Antigen into Antibody-charged Agar in Wintrobe Hæmatocrit Tubes accelerated by Centrifugation

Abstract

THE methods of immunodiffusion and precipitation in gel media offer, over precipitation in fluid media or in interfaces, the advantage of creating automatically self-diluting gradients of concentrations of one or the two reactants, and thus, in a single tube or plate, the optimal conditions for reaction and aggregation (zone of equivalence). The chances of detecting a reaction in a single tube by the ring precipitation method are dependent on the pre- or post-zonal conditions since excess of one reactant dissolves the precipitate of antigen–antibody complex. Hence the need for serial dilutions even for qualitative evaluation.