Abstract: | In this study, activated platelet‐derived vesicles (Act‐VEs) are developed as a novel hemostatic biomaterial. Spherical Act‐VEs (114.40 ± 11.69 nm in size) with surface charges of ?24.73 ± 1.32 mV are successfully prepared from thrombin‐activated murine platelets with high surface expression of active glycoprotein IIb/IIIa (GP IIb/IIIa, also known as αIIbβ3) and P‐selectin. Although nanosized vesicles from resting platelets (VEs) and Act‐VEs showed similar sizes and surface charges, Act‐VEs formed much larger aggregates in the presence of thrombin and CaCl2, compared to VEs. After incubation with fibrinogen, Act‐VEs formed much denser fibrin networks compared to platelets or VEs, probably due to active αIIbβ3 on the surfaces of the Act‐VEs. After intravenous injection of the Act‐VEs, tail bleeding time and the blood loss are greatly reduced by Act‐VEs in vivo. In addition, Act‐VEs showed approximately sevenfold lower release of pro‐inflammatory interleukin‐1β (IL‐1β) during incubation for 4 days, compared to platelets. Taken together, the formulated Act‐VEs can serve as a promising hemostatic biomaterial for the efficient formation of fibrin clots without releasing pro‐inflammatory cytokine. |