No More Tricky Welding We all know t h a t making a good micro-electrode for voltammetry requires skillful hands. Welding metal wires to glass tubing can be tricky. One has to make the proper match between the metal and the type of glass used, otherwise unavoidable cracks may develop just when measurements are being taken. Making platinum wire electrodes may be easy because of the metal's high melting point which allows handling it in the flame without too much worry. But, what about making a gold or a silver electrode? T h e low melting points of gold and silver together with the solubility of silver in fused glass is enough t o discourage anyone twine to make a m o d micro-electrode.
use. Our new way of making wire electrodes is shown in the figure. Here a double wire electrode for use in differentialelectrolytic patentiometry is shown.
Diagram of micro-electrode a) ordinary glass tubing b) rubber cement stoppers c ) piatinurn, gold, silver, w other metal wires, punched through rubber stopper d) isolated electric cable
Pablo Cofre G. lnstituto de Ciencias (luimicas Pontificia Universidad CatOlica de Chile. VicuOa Mackenna 4860. Santiago. Chile
Volume 60
Number 5
May 1983
421
