Abstract: A method and device for the preparative scale recovery of a protein or other charged macromolecule by electrophoretic separation of a mixture of such macromolecules. The device is adapted to be installed between the electrodes of an electrophoretic cell and includes a gel receiving receptacle adapted to hold the end of a gel slab or gel fragments containing an electrophoretically separated macromolecule. An aperture in the base of the receptacle is covered by a first membrane which is substantially permeable to the macromolecules desired to be recovered and a second membrane substantially impermeable to the macromolecules to be recovered but permeable to electrolyte molecules in a buffer solution used in electrophoresis. The two membranes lie in spaced apart array with one another to define therebetween a recovery space. Means are provided to allow the periodic or continuous withdrawal of buffer solution and macromolecules from the recovery space.