Abstract: A pulsed-field gradient gel electrophoretic apparatus is described wherein a free standing gel is employed. Electrode arrays are oriented to provide three dimensional fields across the face of the gel rather than in the plane of the gel. The electrodes produce three dimensional fields which are orthogonally oriented with respect to each other and cause the molecules to proceed down the lanes in the gel in a generally saw-tooth manner oscillating between the surfaces thereof. Alternately, three dimensional, electric fields are arranged at angles greater than 90.degree. to one another across the face of the gel in separating the molecules, following which transfer electrodes are substituted for the separation electrodes in order to transfer the molecules from their separation lanes onto a separate substrate.