ABSTRACT
Microcapsules are used in the biomedical field for sustained or slow release dosage forms, artificial cells, and artificial organs. In the biomedical applications, microcapsules inevitably come into contact with blood to experience different types of interaction with blood components, depending on the chemical structure and physicochemical properties of the constituent polymer. The presence of high concentrations of plasma proteins in the bulk phase would also contribute to raise the rate of microcapsule degradation through the high capacity of protein molecules to solubilize the poly(l-lactide) molecules of low degrees of polymerization released from the microcapsules. Platelet adhesion to the surface of microcapsules is an important problem to be tackled because it is possible that microcapsules join together through the adhered platelets to form large aggregates which may give rise to thrombosis when they are introduced into the blood stream. When microcapsules come into contact with blood, competitive adsorption of plasma proteins to the microcapsule surface takes place.
