Polystyrene nanoparticles affecting blood coagulation

The association of nanoparticles (NPs) with blood coagulation proteins may influence the natural balance between pro-and anticoagulant pathways. We investigated whether polystyrene NPs, when added to human plasma, affected the generation of thrombin in plasma. Amine-modified NPs were found to decrease the thrombin formation due to binding of factors VII and IX to the NPs, which resulted in depletion of the respective protein in solution. In contrast, carboxyl-modified NPs were able to act as a surface for activation of the intrinsic pathway of blood coagulation in plasma. These results highlight the influence of NPs on a biologically important pathway. From the Clinical Editor: With the expected introduction of several nanoparticle-based therapeutic and diagnostic methods in the near future, their impact on basic homeostasis and obligatory biological processes needs to be carefully and accurately studied. In this study, the effects of polystyrene NP-s was investigated on blood coagulation pathways, and critically important biomodulatory effects were found. (C) 2012 Elsevier Inc. All rights reserved.