Iron Assay Kit is a quantitative colorimetric iron determination at 590 nm.This kit is designed to measure total iron directly in serum without any pretreatment. The improved method utilizes a chromogen that forms a blue colored complex specifically with Fe2+. Fe3+ in the sample is reduced to Fe2+, thus allowing the assay for total iron concentration. The intensity of the color, measured at 590 nm, is directly proportional to the iron concentration in the sample.