Electrical Connections to Microelectrodes

The electrical connection from a glass microelectrode to its accompanying electronics is made by a metal wire inserted in the stem end of the lumen and in contact with the filling electrolyte. Early literature frequently refers to tungsten wire for this purpose, but there seems to be no valid basis for using this metal. Apparently it was available and had been used in place of antimony in certain pH electrodes. Because of its metallurgical properties, tungsten is difficult to form, and it has undesirable electrical characteristics. 

Presently platinum or silver wire is generally used to connect into glass electrodes. In some cases, the silver wire is chlorided to make a reversible-electrode connector. Reversible electrodes are discussed in Chapter 5. 

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