lyophilized powder, 3-8 TIU/mg solid
This product is a lyophilized powder with activity of 3-8 TIU/mg of solid powder. Aprotinin is freely soluble in water (>10 mg/mL) and in aqueous buffers of low ionic strengths. Dilute solutions tend to be less stable than concentrated ones, though solution stability also depends on pH. Aprotinin is relatively stable against denaturation - only thermolysin has been found capable of degrading it at 60-80°C. Sterilizaiton of Aprotinin can be achieved through filtration by a 0.2 μm filter.
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.
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.
Synonym(s): Trasylol; Trypsin inhibitor (basic)
Empirical Formula: C284H432N84O79S7
CAS number: 6511.44
MDL number: MFCD00130541
Storage: 2-8°C