Double replica electroblotting by oscillating electrotransfer

Abstract

AbstractProtein blotting has become an indispensable tool in biochemistry and in many blotting experiments it is desirable to obtain more than one replica from the gel, which would permit the use of different probes or staining of one membrane for protein and using the other(s) for probing. This has proved difficult. The different replicas, which can be produced by existing techniques, are far from identical. However, by using oscillating electrotransfer “double replica electroblotting”, two replicas can be obtained from one gel. The two replicas can be made almost identical by reversing the direction of the current in such a way that the efficient transfer time is increased with each period until the gel is almost completely depleted of proteins. The technique is useful for comparison of the reactions of different antisera with one or several antigen samples. Double replica electroblotting has been utilized for ordinary sodium dodecyl sulfate‐polyacrylamide gels, for two‐dimensional polyacrylamide gels and for thin gradient gels analyzed with the PhastSystem (Pharmacia). Double replica electroblotting can, in principle, be used with any blotting system where transfer from the gel to the new medium is achieved by electrophoresis, except in semi‐dry electroblotting with a discontinuous buffer system.