ENZYME IMMOBILIZATION

Enzyme immobilization is the restriction of enzyme activity with in a defined space so that it can be reused.

Advantages of enzyme immobilization:

• enzyme can be retained within the reactor. If not immobilized the enzyme leaves the reactor along with the product.
• product recovery will be easy as the enzyme (it hinders recovery of product) is contained.
• immobilized enzymes retain activity for a longer periods of time than the free enzymes.
• The local environment created near the enzyme due to the support buffering pH, removing toxins etc protect the enzyme from the fluctuations in conditions and from inhibitors.
• The enzyme is stabilized in an immobilized state as immobilization prevents aggregation of enzymes, unfolding, dissociation of multiunit enzymes.
• If the reaction involves/requires a series of enzymes, the enzymes can be positioned correct in catalytic sequence which cant be achieved using free enzyme, thus increasing efficiency.

Disdvantages:

• Due to immobilization the substrate is not easily available to the enzyme. The substrate has to encounter the resistance while passing through 1) the film around the immobilized enzyme and 2) through the matrix. These resistances are referred to as :

1) EMTR : External Mass Transfer Resistance
2) IMTR : Inertnal Mass Transfer Resistance

• These resistances delay the processs.