Apparatus for conducting electrophoresis therein includes a chamber with a gel matrix. The chamber has a first sealed region and a second sealed region, and an anode within the first sealed region of the chamber and in contact with the gel matrix, and a cathode within the second sealed region and in contact with the gel matrix. At least one of the electrodes also provides ions for driving the electrophoresis. The apparatus further includes a matrix with at least one sparingly water-soluble salt.