HIGH-PERFORMANCE LIQUID-CHROMATOGRAPHIC SEPARATION OF APROTININ-LIKE INHIBITORS AND THEIR DETERMINATION IN VERY SMALL AMOUNTS

A reversed-phase high-performance liquid chromatographic method for th e determination and quantitative recovery of fully active aprotinin (t he basic pancreatic trypsin inhibitor or Kunitz inhibitor) and aprotin in-like inhibitors in amounts down to 0.5 mug is reported. The method, which allows separation of aprotinin isoinhibitors characterized by s mall differences in the primary structure with respect to aprotinin it self, appears to be suitable for the quantitation and identification o f aprotinin-like inhibitors in human biological fluids, in which they appear to be present at very low levels.