Staining of proteins after isoelectric focusing in gels by new procedures.

Four procedures are described for staining of protein bands after isoelectric focusing in polyacrylamide gels. In one procedure, Coomassie Brilliant Blue R 250 is used whereas in the others the G 250 form is used in an aqueous solution of perchloric acid. By using isoelectric focusing and the new staining procedures it is possible to detect less than 0.2 microng of many proteins. One of the procedures is especially rapid, allowing detection of proteins without destaining. Procedures for preservation of the protein patterns and determination of proteins by scanning in a densitometer are also described.