Effect of citrate on ultrafiltrable and ionic calcium concentrations in serum

Abstract

The effect of citrate on the concentration of ultrafiltrable and ionic calcium in blood serum and bovine serum albumin (BSA) solutions was studied. Theoretical equations were derived which predict the fractions of total calcium (in simultaneous equilibrium with protein and citrate) which are ultrafiltrable and ionized. The predictions were made directly from concentrations of total protein, calcium and citrate, and pH. Ultrafiltration experiments on purified BSA, rabbit serum containing added citrate, and human blood-bank serum with acid citrate dextrose solution, yielded data which were in good agreement with predicted values. Additional experiments were performed in order to obtain an empirical expression relating pH to the dissociation of calcium proteinate in normal human serum. Submitted on July 3, 1961