Development of dropping carbon fluid electrodes for polarography

Another type of polarography was investigated using a dropping carbon fluid electrode composed of graphite powder and a mixture of dioctyl phthalate and diiodomethane. The reproducibility of the drop size was improved by changing the tip of capillary and the composition of carbon fluid. Polarograms with clear limiting currents were observed when the concentration of reactant, ferrocenecarboxylate (FcCOO−), was lower than 80 μM. The dependence of the limiting currents on the flow rate of the electrode and the concentration of FcCOO− were approximately consistent with the prediction from Ilkovič equation.