The electrochemical characteristics of the lipid-lowering drug simvastatin were investigated on graphite and mercury electrode. Solid microparticles of simvastatin were mechanically immobilized on the surface of graphite electrode and immersed into aqueous electrolyte. The microparticles were oxidized at 1.1 V in totally irreversible electrode reaction. Simvastatin dissolved in acetonitrile and admixed with 0.1 M Na2B4O7-KH2PO4 aqueous buffer solution pH 7 is strongly adsorbed on the surface of mercury electrode. Adsorbed simvastatin was reduced at - 1.45 V in the fast and reversible electrode reaction followed by a chemical reaction. (c) 2006 Elsevier B.V. All rights reserved.