Platelet Response on Poly(D,L -lactide-co-glycolide) (PLGA) Film with Nano-structured Fillers

Thrombosis is a frequent complication associated with blood-contacting devices such as catheters and artificial stents. Current control of thrombus formation via use of anticoagulant therapies is clearly not ideal, as complications such as thrombocytopenia, neutropenia and hemorrhage can arise due to their usage. To avoid these problems, biomaterials with higher level of blood compatibility are necessary. Platelet adhesion and activation onto an implant surface are crucial events in the formation of thrombus resulting from the interaction between the flowing blood and, the foreign material. Surface chemistry and topography are the parameters that greatly determine the adhesion of platelets to a surface. While a lot of research has been performed on the development of materials, the effect of surface topography on platelet adhesion is relatively unexplored. In this work, we show evidence that a nano structured polymer surface significantly reduces platelet adhesion as compared to pristine films. Nano-structured fillers were prepared on poly(D,L -lactide-co-glycolide) (PLGA) films by infiltrating a PLGA solution into a nano porous anodized alumina (NPAA) template. The aspect ratio of the nano-sized fillers proved to be one of the important parameter influencing the amount of platelet adhesion. The results indicate that nanotopographic modifications of surfaces can elicit desired interfacial platelet response which could be significant in the development for new polymeric blood-contacting materials with low thrombogenicity.