Analysis of Total and Transferrin-Bound Iron in Human Serum for Pharmacokinetic Studies of Iron–Sucrose Formulations

Abstract

Patients with iron-deficiency anemia benefit from intravenous iron therapies. Development of these pharmaceutical agents requires pharmacokinetic studies monitoring levels of both the administered agent and transferrin-bound iron (TBI). Successful pharmacokinetic methods must discriminate iron species. Routine colorimetric procedures were used to reliably measure total iron and TBI following iron-sucrose administration. Iron was liberated from iron-sucrose allowing the determination of all circulating iron. Solid-phase sample processing allowed the measurement of TBI. Circulating iron-sucrose could then be calculated as the difference between total iron and TBI. A reproducible and robust spectrophotometric method was developed and validated for measuring total iron and TBI in human serum following iron-sucrose therapy.