Abstract: The 160/180 kinetic isotope effect (KIE) associated with an a-chymotrypsin- catalyzed transestenfication was measured by using the technique of permeable membrane/mass spectroscopy. This almost in situ method is based upon the ability of the ester product, but not water and other polar compounds, to permeate through a dimethyl silicone membrane, which separates the aqueous reaction solution from the evacuated ...
