A Quantitative Study of Antigen-Antibody Combination during Disk Electrophoresis in Acrylamide Gel using Iodine-131 Labelled Human Growth Hormone.

An adaptation of the technique of disk electrophoresis is described. It allows combination of antigen and antibody, as well as the separation of the free antigen from the complex, in a single electrophoretic step. An Iodine-131 labelled human growth hormone : antihuman growth hormone system was used to demonstrate this combination which was expressed as per cent radioactivity bound to immune γ-globulin. Dilution of antiserum gave reproducible titration curves when run at three different temperatures: 10°, 20°, 35°. The curves obtained at 35° showed increased binding. The reduction of bound radioactivity on addition of unlabelled growth hormone to the sample was a linear function of the logarithm of unlabelled growth hormone. The standard curves obtained are suitable for a highly sensitive assay of human growth hormone. [ABSTRACT FROM AUTHOR]