Manual NephelometricMethodsfor Immunochemical

Manual procedures are presented for determining immunoglobulins IgG, IgA, and 1gM in human serum. The three immunoglobulins are quantitated, after reaction with specific ant sera, by measuring light scattering by the antigen-antibody complexes. The procedure is standardized by use of pooled human serum with known concentrations of IgG, IgA, and 1gM. Results with the present system correlated excellently with results of either radial immunodiffusion or an automated immunochemical procedure. Precision of duplicate determinations for the lgG, IgA, and 1gM methods is 5.37, 1.30, and 5.36% (CV), respectively.