[Potential coulometry, a new methodology for the determination of iron concentration in serum. Comparison with the bathophenanthroline method in protein-free solution (author's transl)].

Iron concentration was determined by the aid of the ESA Ferrochem 3050 analyzer and the bathophenanthroline method with deproteinization. Both methods showed a good precision and accuracy. The investigation was carried out in 505 sera with an iron concentration between 9 and 333 micrograms/dl. The comparison of the two methods in 360 sera with normal iron concentration (40-150 micrograms/dl) showed a close correlation (correlation coefficient r = 0.965). Close correlation (correlation coefficient r = 0.939) was also found in the 35 sera with increased iron concentration (150-333 micrograms/dl) and acceptable correlation (correlation coefficient r = 0.808) resulted in the 110 sera with decreased iron concentration (9-40 micrograms/dl). The special merits of the potential coulometric method were precision, quickness in the time of analysis and very small sample size (50 microliters), important for pediatric analyses.