Inner surfaces of pipettes were silanized by drawing liquid trimethylchlorosilane up into the pipette for several minutes. Following treatment, the trimethylchlorosilane was expelled, and the pipette was dried under flowing N2. The pipettes were filled with electrolyte solutions using a flexible microsyringe. The aqueous solution was dispensed at the top opening of the pipette and allowed to wick down the filament to fill the tip. If one tries to fill the tip directly, then bubbles may form and are difficult to remove. The nonaqueous electrolyte was simply dispensed into the tip and bubbles rarely form or persist if they do. The AgCl electrode was placed in the aqueous solution and the Ag pseudo reference was placed in the nonaqueous solution.