Method of preparing a biological glue capable of coagulating by simple addition of calcium ions

By contacting a blood plasma with an activator of the contact phase of blood coagulation prior to or during the preparation of a biological glue based on fibrinogen, a fibrin glue is obtained preactivated which does not coagulate spontaneously but which is capable of coagulate in less than 5 minutes by merely adding calcium ions, without adding thrombin. Application to the surgical field.