A composition for use in external detection and localization of thrombi

The patent deals with a method of locating thrombi in vivo, comprising the steps of administering a radiolabelled peptide selected from the group consisting of Fragment E1 isolated from cross-linked fibrin, Fragment E2 isolated from cross-linked fibrin, and peptides having an amino acid sequence intermediate between Fragments E1, and E2 derived from cross-linked fibrin by plasmin digestion to a human or animal wherein the peptide, is selectively incorporated or bound by forming a preformed thrombi and externally detecting the radiation emitted by the radiolabelled peptide. A composition containing the peptide used for locating thrombi is also disclosed. 6 tabs