Compositions and methods are provided for preparing a metal substrate
having a uniform textured surface with a plurality of indentations with a
diameter in the nanometer and micrometer range. The textured surface is
produced by exposing the substrate to an etching fluid comprising a
hydrogen halide acid and/or an oxyacid, a chloride containing compound,
and an oxidizing agent. The etching solution can be used at ambient
temperature without damaging the metal elements on the substrate surface.
This textured surface enhances adherence of coatings or cells onto the
textured surface, improves the retention of proteins on the surface, and
encourages bone in-growth.