Dry analysis element for the analysis of iron ions

Abstract

A dry analysis element for the analysis of iron ions, which is improved in selectivity so that iron ions can be analyzed reliably at a high sensitivity without the interferences by the presence of hindering Cu.sup.2+ and/or Zn.sup.2+ ions. The analysis element comprises a detection reagent layer containing Nitro-PAPS acting as a chelating agent and a cationic compound, and a pre-treating layer containing a Cu.sup.2+ -specific chelating agent. The analysis element further includes a pH buffer for keeping the pH value of the detection reagent layer within the range of from pH 3.0 to 5.0. The pH adjusting buffer may be contained in either one of the detection reagent layer or the pre-treating layer, or may be contained in another layer. The detection reagent layer may be composed of a coloring reagent layer containing Nitro-PAPS acting as the chelating agent, and a diffusion-preventing layer laminated on the coloring reagent layer and containing the cationic compound.

Dependencies are inferred from the claim text.