Comparison of Bathophenanthroline Sulfonate and Ferene as Chromogens in Colorimetric Measurement of Low Hepatic Iron Concentration

Sensitive and accurate measurement of hepatic iron concentration (HIC) is required to investigate liver fibrogenesis (1) and its influence on the outcome of interferon therapy for chronic viral hepatitis C (2)(3). Hepatic iron content can be measured by a quantitative chemical method and/or evaluated by semiquantitative histologic scoring. Quantitative chemical methods assess all liver iron forms, whereas histologic scoring evaluates only the hemosiderin form. A colorimetric method using bathophenanthroline sulfonate as chromogen was recommended in 1978 by the International Committee for Standardization in Hematology (ICSH) for determination of serum iron (4)(5). It was adapted by Barry and Sherlock (6) to the determination of HIC, and we recently evaluated it for measurement of low HIC (7). In 1990, the ICSH replaced bathophenanthroline sulfonate with ferene, a more sensitive chromogen, in the determination of serum iron (8). The aim of the present study was to evaluate the replacement of bathophenanthroline sulfonate with ferene to improve the sensitivity of the colorimetric determination of low HIC.