Improved direct determination of serum iron

Ferene(TM) (Diagnostic Chemicals LTD, Canada) is used as the chromogenic agent in an improved direct method for determining serum iron. The colour reagent contains hydroxylamine, a reducing agent stable in solution, and a protein solubilizer to avoid deproteinization. The interference of serum copper is eliminated by complexation with thiourea. Reliability of the method has been established by a separate study of the reaction parameters, replicate analysis and recovery experiments. The results obtained by the proposed method correlate well with results of atomic absorption spectroscopy. A fully automated application is also proposed using a centrifugal analyzer with starter dispenser.