Wet chemical methods were used in combination with in situ infrared spectroscopy to identify and quantify soluble products formed during ethylene glycol electrochemical oxidation on platinum. A small volume electrolysis technique allowed reactions to be performed in samples of 150 mu l in contact with a small, bead-type single crystal electrode. Following reaction, 50-100 mu l aliquots were assayed for aldehydes and carboxylic acids. Glycolaldehyde (HOCH2CHO), and glycolic (HOCH2COOH) and oxalic ((HOOC)(2)) acids were detected following the 360 s electrolysis of 0.2 M ethylene glycol in 0.1 M HClO4 at potentials in the range 0.0-0.6 V (vs. SCE). Determination of the carboxylic acids by ion chromatography aided the assignment of carboxylate vibrational bands in in situ infrared spectra.