A stable 4 mol% yttria-stabilized zirconia (YSZ) sol has been synthesized for coating stainless steel AISI 316L for biomedical applications. The sol was prepared by controlled hydrolysis of zirconium n-butoxide using acetylacetone and nitric acid as chelating agent and catalyst, respectively. X-ray diffractograms of calcined YSZ xerogel indicated a tetragonal structure at temperature as low as 400 degrees C. Stainless steel was dip-coated in transparent yellow YSZ sol followed by heat treatment between 400 and 600 degrees C for 2 h in air. A homogeneous and crack-free YSZ film was, thus, obtained on the stainless steel surface. Adhesion strength, measured by scratch test in progressive loading sequence on coated AISI 3161, showed 27 +/- 3 N critical load. Corrosion performance of the surface coating was evaluated through open-circuit potential (OCP) measurement, impedance, polarization and chronoamperometry in Ringer's solution at 37 degrees C. The coating enhanced the pitting potential of the substrate. The metal ions released from AISI 316L was effectively controlled by the coating. (C) 2008 Elsevier B.V. All rights reserved.