Matrix effects in the determination of zinc(II) ion in whole rat liver by flame atomic absorption spectrometry
Analytical systems that might be of practical importance for the direct determination of ZnII ion in whole rat liver homogenates by flame atomic absorption spectrometry were reliably evaluated based on the change in calibration sensitivity. For that purpose synthetic samples were prepared in three extremely different media for tissue homogenization. Hydrochloric acid medium proved to be more resistant to matrix components (non-ionic detergent, albumin, inorganic salts) than water or Tris–acetate buffer (pH 8.7). Further, a highly acidic medium allows the substitution of complex albumin and salt-containing standard solutions with simple acidic and even aqueous solutions. The convenience of 1.0 mol l–1 HCl as the medium for rat liver homogenization is emphasized, owing not only to quantitative extraction of metal ions but also to markedly reduced matrix effects.