The electrokinetic potentials of anatase (titanium dioxide) and alpha-alumina were studied by means of various instruments in the presence of sodium and potassium trichloroacetates, trifluoroacetates, and trifluoromethanesulfonates at various pH, ionic strengths, and solid-to-liquid ratios. At concentrations up to 0.01 M, these salts do not induce substantial shifts in the isoelectric point of the oxides. Such behavior is typical of inert electrolytes. (c) 2007 Elsevier Inc. All rights reserved.