Effect of Excess Charge in Cellulosic Polyelectrolyte Complexes on the Blood Compatibility

Abstract

The effect of excess charge in cellulosic polyelectrolyte complexes (PECs) on the blood compatibility was examined in detail. For this purpose, various ex cess charge PECs were prepared from a quaternary ammonium derivative of hydroxyethyl cellulose (Q-HEC) and carboxymethyl cellulose (CMC). The blood compatibility of the PECs was evaluated by three different test methods; Lee- White, platelet adhesion and contact phase activation tests, as well as by the "Quenched Lee-White test" which determines time-variant changes in the differentiated hematological responses during whole blood coagulation. The three test results showed that relative coagulation time of whole blood is very long and almost independent of the mole ratio of polycation to polyanion components within the mole ratios examined, but platelet adhesion increases with increasing mole ratios of polycation/polyanion in the PEC, while contact phase activation of plasma coagulation increases with decreasing mole ratio. However, the "Quenched Lee-White test" revealed that platelet counts and quantity of the hematological factors measured after 15 min are independent of the excess charge on PECs and maintained at the considerably high level even at 60 min of exposure time, indicating weak interaction of blood with PECs irrespective of surface charge excess. This may result in good antithrom bogenicity in both in vivo and in vitro under longer-term experiments.