Determination of oxidizable solutes in water is accomplished using amperometric detection in a solution exchange apparatus. The applied potential (E a ) used is +0.5 V vs. SCE at n nickel working electrode. Electrode pretreatment is performed at -1.0 V vs. SCE. The background electrolyte is 0.1 M NaOH. Analyte solution drawn into the cell replaces background solution. No further convection occurs. Peak anodic current relative to the baseline is used as the analytical signal. The linear range extends down to 1 μM for sucrose, diethylenetriamine, phenol, and ethanolamine. The determination time is 2 min per sample.