3. Heterogeneous kinetics

3.1 Enzyme immobilization methods

As early as 1916, Nelson and Griffith observed that invertase, which catalyzes the hydrolysis of sucrose into glucose and fructose, retained its activity when adsorbed on activated carbon or aluminum hydroxide. However, work on enzyme immobilization only really took off when these biocatalysts became effectively available on an industrial scale. Immobilizing an enzyme enables it to be used in a continuous reactor, or recovered and reused. This can significantly improve the economics of an enzymatic process, especially as the cost of the enzyme is high. This benefit is very often enhanced by the fact that immobilization results in a very significant increase in enzyme stability, due to the preservation of the active three-dimensional structure. This...