S-2238, Chromogenic Substrate for Thrombin

S-2238, which is specific to thrombin, is a short peptide covalently bound to pNA (4-nitroaniline). When attacked by thrombin, it gives up a free pNA which could be detected by a spectrophotometer at 405 nm.

S-2238 is mainly used in anti-FIIa activity assay of heparin.


S-2238 can be used in many applications, such as:

  1. Anti-factor Xa activity to anti-factor IIa activity ratios of heparin and LMWHs
  2. Anti-factor IIa activities of heparin and LMWHs
  3. Activities of antithrombin and thrombin
  4. Anti-factor IIa activities of heparin and LMWHs in human plasma
  5. Production of kits for automated blood analyzers
  6. Evaluation of potential anticoagulants from chemical synthesis, bacterial fermentation and animal tissues


S-2238 is white lyophizied powder, stored in vials.

Each vial contains: S-2238 10 mg (15 μmol); mannitol 120 mg.

Physical and Chemical Properties

Synonyms: S-2238, thrombin substrate

CAS number: 113711-77-6

Molecular formula: H-D-Phe-Pip-Arg-pNA·2HCl

Molecular weight: 625.6 Da

Purity: ≥ 99% (HPLC)

Absorption coefficient: A405nm ≤ 0.120 [L/(g·cm)]

Solubility: > 10 mg/mL (in pure water)


Reconstitute the entire contents of a vial, dissolve it with 5 mL distilled water to get a solution with concentration of 3 mmol/mL S-2238.

Stability and Storage

The lyophilized powder of S-2238 could be preserved at 2 to 8 ℃ for at least 24 months.

The 3 mmol/mL S-2238 solution could be preserved at 2 to 8 ℃ for about 1 month.

Order Information

Catalog number: AG00-0101

Package size & price:

Packing size Price (USD)
10×10 mg 910.00


S-2238 is only used for lab researches. Do NOT use it as drugs or in vivo experiments.

See more about chromogenic assays.

Click the links to see the anti-FIIa assay for low-molecular-weight heparins.

Anti-FIIa Assay: Solutions

Anti-FIIa Assay: Procedure