Surface-enhanced Raman spectra (SERS) from a roughened platinum electrode in formic acid-containing dimethylformamide solutions have been examined combined with cyclic voltammetry techniques. The occurrence of surface poisoning by CO adsorption was confirmed by observation of both Pt-CO and internal CO modes simultaneously. Oxidation of HCOOH can occur to a large extent only after the desorption of CO from the surface. Similar observations were also obtained in absolute methanol solutions. Linearly bound CO on platinum was suggested for both nonaqueous systems. In addition, a high electro-catalytic activity for the present roughened SERS-active platinum surface was also assumed compared with smooth platinum surfaces. (C) 2003 Elsevier B.V. All rights reserved.