EVALUATION OF A NEW SOLID-STATE REFERENCE ELECTRODE JUNCTION MATERIALFOR ION-SELECTIVE ELECTRODES

The performance and properties of a new low-resistance material, Refex , suitable for use in reference electrode junctions is described. The material is a solid polyvinyl acetate that contains a very large loadi ng of KCl (1:1 w/w KCl/PVA). Despite relatively large active surface a reas in the designs studied (stand-alone reference and combination pH) , leakage rates of KCl are remarkably low. pH measurements in ultrapur e water and comparative measurements in common buffer solutions agains t: standard reference electrodes confirm the st ability of the potenti al developed across the junction to be very stable. Impedance studies verify the importance of the KCl doping for realization of the low res istance and attractive electrochemical properties of the material.