A way had been found to recognize infectious blood donations and to sort them out. Blumberg used the agar gel double diffusion developed by Ouchterlony in the discovery of AuAg. Compared to the biochemical methods of protein determination, the Ouchterlony method was fairly sensitive and specific...
For infection diagnostics, however, the test was in most cases not sensitive enough. Although blood donation facilities were soon examining all of their donors for AuAg, many post-transfusion hepatitis B infections continued to appear. Thus, the agar gel diffusion and similar methods were only a...