A split-disk, dual-electrode amperometric cell was constructed and tested using biogenic amines as the model analytes. Advantages of the cell include a small working volume (less than 1.8 pL), favorable hydrodynamic conditions, and the fact that the system can be used in parallel-adjacent and series arrangements with the same geometry. The collection efficiency on the downstream electrode in the series arrangement is high (around 38% for reversible electrode reactions) and is very close to the theoretical value. The differences in the collection efficiencies for electrode reactions with different degrees of reversibility can improve the selectivity of measurement and assist identification of the SubStdnCeS. Selectivity is greatly improved in the pdrdlkl-adjaCent arrangement where one electrode is activated by galvanostatic pretreatment while the other is only mechanically polished.