Trypsin Inhibitors Assay
Method: The ability of the various trypsin inhibitors to prevent trypsin hydrolysis of benzoyl-L-arginine ethyl ester is measured spectrophotometrically. No unit of activity is currently assigned. The activity of the inhibitors is expressed as the amount of twice crystallized trypsin (TRL) inhibited by one milligram of inhibitor.
Pipette the following into a series of test tubes:
Include 2 test tubes with no inhibitor as controls.
* The following amounts are recommended:
Incubate tubes at room temperature for 30 minutes. Dilute an aliquot with an equal portion of water and assay for residual trypsin activity. Set spectrophotometer at 25°C and 253 nm. Pipette 2.9 ml of trypsin reagent into cuvette and incubate in spectrophotometer for 3-4 minutes to achieve temperature equilibration and establish blank rate, if any. Add 0.1 ml diluted incubation mixture and record increase in A253 for 3-4 minutes. Determine ΔA253/minute from initial linear portion of curve.