What is an immobilised enzyme and what are the advantages of their use?

Immobilised enzymes are enzymes that have been trapped into an inert matrix or material (such as calcium alginate) which prevents them from moving during the reaction process. Whole cells such as yeast and bacterial cells can also be immbolised to enable the usage of specific enzymes contained within the cells. There are a number of advantages to using immobilised enzymes. One advantage is that it makes recovery and reuse of the enzymes far more straightforward. This is particularly advantageous where the enzyme may be hard (or expensive) to produce. Immobilisation offers greater enzyme stability in variable or extreme temperatures and pH. This increased stability helps maintain greater efficiency of the reaction process. Immobilisation also ensures that the enzyme does not contaminate the final product of the reaction. Contamination is prevented because the enzymes are physically trapped by the matrix. Immobilisation of whole cells for use in reactions is advantageous because it means multiple enzymes within the cell can work simultaneously. Simultaneous use of the enzymes in this way reduces the number of steps and overall costs of the reaction process.