Determination of iron in calf serum using bathophenanthroline and thermal lens spectrometry

Thermal lens spectrometry has been used for the determination of iron in ca lf serum. The method is based on dissociation of Fe3+ from proteins, reduct ion of Fe3+ to Fe2+ and formation of a coloured complex between Fe2+ and ba thophenanthroline. Contrary to the spectrophotometric method, it is shown t hat thermal lens spectrometry is less sensitive to scattering caused by the presence of small particles remaining in the test solution after the depro teinization step. The background signal is very small and the response is o nly slightly dependent on the amount of scattering particles. The method is reliable, sensitive and reproducible. The limit of detection for iron is 4 ppb and the relative standard deviation is around 2%. It is expected that the volume of serum sample necessary for an analysis can be reduced to less than 100 mul.