Centrifugal analysis for serum iron and iron-binding capacity using the IL Multistat III Analyzer

A colorimetric method for the determination of serum iron and total iron-binding capacity (TIBC) has been adapted to an IL Multistat III Centrifugal Analyzer. The correlation to an ESA Ferrochem, Model 3050, which measures iron by coulometry, is acceptable (IL Multistat = 1.08 ESA--5.05). The intra-run precision gave an average C.V. of less than 5%. The day-to-day precision was between 2% and 7% and the average analytical recovery was 102%. This method requires only 150 microliters of sample for both iron and TIBC which is a significant advantage over many existing methods in terms of sample volume, especially when a pediatric population is considered. Both iron and TIBC may be analyzed at the same time on the same rotor. The approximate analysis time is 30 minutes for seven iron and TIBC samples, four controls and one standard. The cost is low, being approximately $0.08 per iron assay and $0.83 per TIBC assay.