Biomedical behavior of synthetic polyion complexes toward blood platelets

A group of polyion complexes (PICs) was checked as candidate for non‐thrombogenic biomaterials. To evaluate blood‐compatibility of different types of PIC, the interaction of the PICs with blood platelets was examined by passing fresh blood through a column packed with glass beads which were precoated with PIC. The course of morphological change of the platelets adhered on the surface was observed by scanning electron microscopy. The behavior (adhesion, aggregation, and deformation) of the platelets on the beads' surface was found to be significantly influenced by the mole ratio of polyanion to polycation in the PIC. The blood‐compatibility could be shown to depend also on the chemical structure of the polycation component of the PIC. Among the PICs examined, the newly synthesized PIC 5 showed the best results in terms of the number of adherent platelets and the degree of their deformation. The good blood‐compatibility of 5 is presumabley attributable to the easiness in getting to stoichiometric neutralization.