Abstract: Devices and methods are provided for more efficiently performing electrophoresis and electroblotting. A sandwich structure includes an electrophoresis gel affixed to a blotting membrane. A gel casting and/or running frame is used to hold the sandwich. A method and composition that allows separation of the gel and membrane after performing a combined electrophoresis and electroblotting operation so as to allow further operations to be performed individually upon the membrane, gel or both. A uniform electrophoretic field may be created by surrounding the sandwich structure using an insulating fluid; the insulating fluid is then swapped for a conducting fluid to allow application of an electroblotting field. An apparatus automatically manages fluid exchange and actuation of electrophoresis and electroblotting electrodes. A plurality of parallel cavities may be used to hold multiple gels or gel membrane sandwiches.