A versatile macro- to micro-size stationary mercury drop electrode

A novel electromagnetic controlled needle valve stationary mercury drop electrode, allowing formation of mercury drops of macro- to micro-size ranges (200 μm > r ⩾- 25 μm), has been developed. Cyclic voltammograms and anodic stripping voltammetry measurements for the smaller drops (r < 50 μm) were consistent with microelectrode behaviour. Another attractive feature is that the electrode may be used in any position thus enabling its use in flow through systems.