64815-81-2

H-D-Phe-Pip-Arg-pNA (S-2238), a chromogenic substrate, is patterned after the N-terminal portion of the A alpha chain of fibrinogen, which is the natural substrate of thrombin. H-D-Phe-Pip-Arg-pNA is specific for thrombin and is used to measure antithrombin-heparin cofactor (AT-III). The AT-III assay using H-D-Phe-Pip-Arg-pNA is sensitive, accurate, and easy to perform[1][2].

[1] Goodnight SH Jr, et al. Measurement of antithrombin III in normal and pathologic states using chromogenic substrate S-2238. Comparison with immunoelectrophoretic and factor Xa inhibition assays. Am J Clin Pathol. 1980;73(5):639-647. DOI:10.1093/ajcp/73.5.639
[2] Voorthuizen H, Kluft C. Improved assay conditions for automated antithrombin III determinations with the chromogenic substrate S-2238. Thromb Haemost. 1984;52(3):350-353. PMID:6531759