The effect of poly-L-lysine/alginate bead membrane characteristics on the absorption of heparin.

During extracorporeal procedures like hemodialysis, heparin is administered to patients to prevent clotting. Unfractionated heparin has side effects such as excessive bleeding. It would be advantageous if the blood could be deheparinased before it returns to the patient. Previous work has indicated that poly-L-lysine/alginate beads can efficiently remove heparin from saline solutions 1. Heparin is irreversibly absorbed onto the beads. This article explores ways of optimizing the absorption process by performing in vitro rate experiments with varying physical parameters of the beads. Fetal calf serum and blood are also used in experiments to investigate the possibility of designing a safe and efficient reactor to absorb heparin. All the experiments were performed to obtain the required parameters for optimal reactor design. The results indicate that the absorption could be optimized by controlling the membrane thickness of the beads. The beads also showed efficient removal of heparin from whole blood.