The relation of the rates of flocculation and amounts of precipitate in precipitin reactions to the concentration of hydrogen ion and of neutral salts.

摘要: The effects of concentration hydrogen ion and neutral salts on the amounts precipitate rates flocculation have been studied with several antigen-antibody systems, in particular those bovine serum albumin (BSA) lysozyme (L) their rabbit antibodies. In all systems amount rate were maximum over a pH range extending both sides 7. pH, which was maximum, narrower than maximum; outside this fell more steeply precipitate. The flocculation, but not formed protein antigens, reduced concentrations sodium chloride above 0.15 N; reduction greater solutions magnesium less sulphate equivalent concentration. precipitates by that relatively small molecular weights, corresponding antibodies, changes antibody; these antigens antibody also affected change salts. It is suggested difference due to presence fewer combining sites smaller molecules albumin. The precipitate, as increased, compatible hypothesis negatively charged group, near 5, each receptor site essential for combination antigen. The through amino groups lose positive charge suggests positively are antigen other evidence, however, indicates essential. The effect increased precipitin curves Type III pneumococcal polysaccharide consistent its reactions antibody. Experiments indicate when salt low it mainly later stages aggregation delayed.