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Unsaturated Iron Binding Capacity (UIBC)

Iron Distribution in the Human Body
The total iron content in the human body ranges from 3 to 3.5 grams. Approximately 2.5 grams of this iron is stored in erythrocytes (red blood cells) or their precursors within the bone marrow. In contrast, the plasma contains only around 2.5 milligrams of iron at any given time.

Iron Transport and the Role of Transferrin
Iron is transported in the blood as Fe(III), which binds to the plasma protein apotransferrin. This complex, known as transferrin, carries iron to tissues throughout the body. Typically, only about one-third of transferrin’s binding sites are occupied by iron.

UIBC and TIBC in Iron Status Evaluation
The unoccupied binding sites on transferrin represent the Unsaturated Iron-Binding Capacity (UIBC). The sum of serum iron and UIBC gives the Total Iron-Binding Capacity (TIBC), which reflects the maximum amount of iron that transferrin can carry.

TIBC Variations in Iron Disorders
TIBC levels fluctuate based on iron metabolism status:

In iron-deficiency anaemia, TIBC is increased and transferrin saturation drops below 15%.

In chronic disease anaemia, malignant tumours, and infections, both serum iron and TIBC are typically low.

Private TIBC and Iron Testing in Slough and Surrounding Areas
Comprehensive iron studies—including serum iron, TIBC, UIBC, and transferrin saturation—are available in Slough, Windsor, Maidenhead, and nearby Berkshire areas. These tests support accurate diagnosis of iron deficiency, iron overload, and chronic inflammatory conditions affecting iron metabolism.