Automated determination of serum (plasma) and urine iron: a comparative investigation of chromogens improved tripyridyltriazine micromethod.

Four different, well known colour reagents for iron determination were tested in a citrate buffer at pH 2.0 under the same automated standard conditions and compared with a manual reference method on human serum and plasma samples. Specific results were obtained only with the chromogen tripyridyl-s-triazine. A micromethod was developed, which is generally well suited for automated, direct serum iron determinations, with respect to good flow properties, simple reagent composition, high reagent stability, rapid colour development, stable colour complex and high specificity. This method was run on either a Gilford System 203 S, Gilford Impact 400 or a Greiner G-400 analyser and adapted to the Technicon SMAC II, Technicon RA 1000, Eppendorf Epos and Abbott Spectrum automated systems. The tripyridyl-s-triazine method permits the determination of ferrioxamine iron in urine after a simple sample pretreatment.