Simplified determination of serum iron and total iron-binding capacity.

2,4,6-Tripyridyl-s-triazine (TPTZ) is a color reagent for ferrous ion in the pH range 2 to 10,when ascorbic acid is used as the reducing agent. In this range TPTZ and ferrous ion combine in the ratio of two to one. Tris buffer is commonly used to maintain an alkaline pH, but it reacts with other reducing agents, rendering them ineffective. These observations suggested a method for the joint determination of serum iron and total iron-binding capacity (TIBC), all done in a single tube and with one color reagent. The method is compared with those of Peters eta!. The standard deviation of the difference between the serum iron methods is less than 6 g/100 ml, between the TI BC methods, less than 19 g/100 ml.