Simple procedure for the removal of nonspecific inhibitors of rubella virus hemagglutination.

The adsorption of serum lipoproteins onto an insoluble matrix of colloidal silicic acid results in the removal of nonspecific inhibitors of rubella virus hemagglutinin. The procedure can be performed in 15 min at room temperature. Comparative studies using both the dextran sulfate-CaCl2 and heparin-MnCl2 methods for removal of inhibitors demonstrated that the colloidal silicic acid procedure yielded identical hemagglutination inhibition titers. In addition, it is technically feasible to read titers below 1:8.