A simple colorimetric method for the determination of iron in serum

Abstract

Iron in serum is freed from its attachment to protein with hydrochloric acid and the proteins are precipitated with trichloroacetic acid. A coloured complex is formed with metamizol in the presence of a high concentration of hydrogen peroxide, the absorption maximum at 440 nm being used for its colorimetric determination. The complex is relatively stable and its absorption obeys Beer-Lambert's law up to 400 µg of iron per 100 ml. Recovery experiments and comparison of a series of determinations with a widely used colorimetric method showed no statistical difference from expected values.