In situ generated thrombin in the protein corona of zeolites: Relevance of the functional proteins to its biological impact

Adsorption of plasma proteins to nanomaterial surfaces has a great influence on their bio-functionality. However, there is limited understanding of the relationship between the functional proteins in the protein corona and the biological identity of the materials. Here we show that the in situ generated thrombin in the protein corona of a Ca-zeolite surface displays a calcium-dependent, unusually high (~3, 000 NIH U/mg) procoagulant activity, which is even stable against antithrombin deactivation. Removing the encapsulated Ca²⁺ in the zeolites leads to deactivation by antithrombin. Our observations suggest that the thrombin activity can be regulated by the inorganic surface and cations. Most importantly, our discovery indicates the link between the biomolecules in the protein corona and the procoagulant activity of the materials, providing a new molecular basis for the procoagulant mechanism for zeolite hemostatics.