6.2.1 Immbilisation Of Enzymes

Question 1

Adsorption / carrier bound enzymes?

Answer 1

Enzyme molecule are mixed with immobilising support, eg glass beads / clay

Question 2

Advantages of adsorption?

Answer 2

Active sites available

Question 3

Disadvantages of adsorption?

Answer 3

Not free to move, so temperature increase does not increase rate of reaction (no more kinetic energy)

Question 4

Covalent bonding / cross-linked enzymes?

Answer 4

Enzyme molecules are covalently bonded to a support

Question 5

Advantages of covalent bonding?

Answer 5

Active site available

Question 6

Disadvantages of covalent bonding?

Answer 6

Enzymes are not free to move within the solution to get to the substrate

Question 7

Entrapment / inclusion?

Answer 7

Enzymes trapped in their natural state inside a gel bead

Question 8

Advantages of entrapment?

Answer 8

Easy to remove from solution; large surface area

Question 9

Disadvantages of entrapment?

Answer 9

Reaction rate can reduce as substrates need to diffuse through the gel

Question 10

Membrane separation?

Answer 10

Substrate separated from the mixture by a partially permeable membrane

Question 11

Advantages of membrane separation?

Answer 11

Easy to remove from solution; large surface area

Question 12

Disadvantages of membrane separation?

Answer 12

Can slow reaction

Question 13

Advantages of immobilised enzymes in general?

Answer 13

Can be reused easily; product is free of enzymes- cheaper; immobilised enzymes are more tolerant to pH and temperature change (insulated), so reactions can be run at a higher temperature