Table 1.

Advantages and disadvantages of the most common methods of enzyme immobilization.

Method of Immobilization	Advantages	Disadvantages
Encapsulation/entrapment	No chemical modification of the enzyme Enzyme should retain catalytic activity under the conditions of polymerization/transition of the support	Enzyme leakage Mass transfer issues
Enzyme cross-linking	No support is needed Stabilization of the enzyme Minimization of catalyst leakage	Possible massive chemical modification of the enzyme Complicated experimental processes Mass transfer issues
Adsorption	No chemical modification of the enzyme Easy and cheap to be performed	Enzyme leakage Low specificity of the reaction (i.e., adsorption and ion-exchange could overlap)
Electrostatic interaction	No chemical modification of the enzyme Easy to be performed	Enzyme leakage Low specificity of the reaction (i.e., ion-exchange and adsorption could overlap)
Affinity	High specificity of the reaction	The presence of specific groups on the enzyme is mandatory Usually expensive and complicated to be designed
Covalent binding	Strength of the binding Minimization of catalyst leakage Stabilization of the enzyme	Possibility sterical modifications of the enzyme Decrease of enzymatic activity is possible Chemical modifications of the support are necessary Usually irreversible attachment, preventing support reuse