Stability of immobilized alpha-chymotrypsin in supercritical carbon dioxide

Inactivation of immobilized alpha-chymotrypsin in supercritical carbon dioxide was with a first-order kinetic behaviour. The increase in either the pressure or the temperature of the fluid enhanced the inactivation process of the enzyme. The fluid density was shown as a key parameter on the enzyme stability, enhancing the half-life time proportionally to the physical phase of CO2, as follows: liquid > supercritical > gas. However, the number of pressurization/depressurization cycles, and the water content of the derivative increased greatly the loss of activity.