In Vitro Binding of Iron With the Cation-Exchange Resin Sodium Polystyrene Sulfonate, ,

Study objective: To investigate the ability of the cation-exchange resin sodium polystyrene sulfonate to bind iron from ferrous sulfate solutions, along with the effects of pH on binding. Methods: We performed a series of in vitro experiments in which various concentrations of iron and sodium polystyrene sulfonate were combined and free ferrous iron was measured with the use of a colorimetric assay. Results: Sodium polystyrene sulfonate bound iron from ferrous sulfate solutions at pH 2 and pH 7. Slightly less binding of free ferrous iron was demonstrated in experiments performed at pH 7 than in those performed at pH 2. At pH 2, 98% of iron was bound; at pH 7, 95% of iron was bound. Conclusion: Sodium polystyrene sulfonate may be a useful therapy in acute iron poisoning once safety and efficacy are determined with the use of in vivo models. [OʹConnor TA, Gruner BA, Gehrke JC, Watling SM, Gehrke CW: In vitro binding of iron with the cation-exchange resin sodium polystyrene sulfonate. Ann Emerg Med November 1996;28:504-507.]