Notes: Cayman’s Total Iron-Binding Capacity (TIBC) and Serum Iron Assay Kit provides a convenient colorimetric method of determining iron levels and UIBC in serum. Measurement of both serum iron and UIBC allows for the calculation of TIBC, which is an estimation of transferrin levels in the serum. This assay has a range of 0-100 µM (0-560 µg/dl) and a lower limit of detection (LLOD) of 0.68 µM (3.8 µg/dl).