Mechanics of Zn modified fibrin network

Fibrin are the main constituent during the hemostasis due to its unique mechanical properties resulting from its hierarchy structure, malfunction of fibrin can lead to diseases such as thrombosis. Here we show Zn can tune the fibrin network and its mechanical properties. In the presence of Zn2+, fibrin protofibrils form huge fiber bundles which are intrinsic loosely coupled. By further comparing with theoretical model, we show that under low stress, the mechanical properties of Zn modified fibrin network are contributed by the thermal fluctuation of the network; at high stress, the mechanical properties are contributed by single protofibril mechanics.