Aprotinin is a competitive serine protease inhibitor that forms stable complexes with and blocks the active sites of enzyme. This binding is reversible, and most aprotinin-protease complexes will dissociate at extreme pH levels >10 or <3. Structurally, Aprotinin is a monomeric globular protein derived from bovine lung that consists of 58 amino acids, arranged in a single polypeptide chain with three crosslinking disulfide bridges.

• Application: Aprotinin is largely used as an inhibitor of trypsin
• Preparation: This product is an aseptically filled solution in 0.9% NaCl and 0.9% benzyl alcohol. It has an activity of 3-7 TIU/mg protein and 3-21 TIU/mL solution.
• Unit definition: One Trypsin Inhibitor Unit (TIU) will decrease the activity of two trypsin units by 50%, where one trypsin unit will hydrolyze 1.0 µmole of N-alpha-benzoyl-DL-arginine p-nitroanilide per minute at pH 7.8 and 25°C. Another commonly used unit is the KIU, with 1 TIU = 1,300 KIU.
• Quality level: Premium (ISO 9001)
• Sterility: Aseptically filled
• Form: Saline solution
• Molecular weight: ~6500
• Solubility: H2O: soluble >10 mg/mL
• Gene Information: Cow ... PTI(404172)
• Storage: 2-8°C
• Synonym: Trasylol, Trypsin inhibitor (basic)
• CAS Number: 9087-70-1
• Empirical Formula: (Hill Notation) C284H432N84O79S7
• Molecular Weight: 6511.44
• MDL Number: MFCD00130541