Patent ID: 7893030

Claim:
A composition comprising: a) a chromogenic peptide substrate, wherein the chromogenic peptide substrate comprises a substrate of thrombin, and wherein the chromogenic group is selected from para-nitroaniline (pNA), 5-amino-2-nitrobenzoic acid (ANBA), 7-amino-4-methoxycoumarin (AMC), quinonylamide (QUA), dimethyl 5-aminoisophthalate (DPA), and their derivatives; and b) an oligopeptide inhibitor of fibrin polymerization, wherein the oligopeptide inhibitor of fibrin polymerization: i. inhibits polymerization of fibrin monomers which are formed under the influence of thrombin; and ii. comprises the peptide sequence GPRP-X—NH 2 (SEQ ID NO: 1), wherein G is the amino acid glycine, P is the amino acid L-proline, R is the amino acid L-arginine, and X is selected from the amino acids alanine and glycine; and wherein the pH of the composition is between 3.0 and 6.0.