A screen-printed planar type solid-state Ag/AgCl reference electrode in which a poly(dimethylsiloxane) (PDMS) emulsion as the material to form the inner electrolyte layer and the liquid junction, was fabricated for improvement of potential stability. The potential stability of the present reference electrode was for longer than 1680h (over 2 months). The present reference electrode was insensitive to important ionic species, including Na(+), K(+), Cl(-) and PO(4)(2-), under continuous measurements. No significant difference of cyclic voltammograms was observed in 10 mM Na(2)SO(4) solution containing 5 mM K(3)[Fe(CN)(6)] and K(4)[Fe(CN)(6)] with the present or a commercial Ag/AgCl reference electrodes. (C) 2011 Elsevier Ltd. All rights reserved.