ChE 128 Enzyme Immobilization

What is the primary feature of adsorption in enzyme immobilization?

Which material is NOT commonly used as a solid support for enzyme immobilization?

Which of the following statements about enzyme inhibitors during covalent bonding is true?

What is a common problem associated with enzyme adsorption?

In covalent bonding during enzyme immobilization, which functional group is irrelevant for bonding?

What is the primary purpose of enzyme immobilization?

Which of the following is NOT an advantage of using immobilized enzymes?

What is a common disadvantage of using immobilized enzymes compared to free enzymes?

Which material is commonly used in matrix entrapment for enzyme immobilization?

What is a key characteristic of a matrix used for pinning enzymes?

Which of the following membrane materials is used for membrane entrapment of enzymes?

Which configuration is popular for separating enzymes from substrates and products?

What is a common misconception regarding the costs associated with immobilized enzymes?

Enzyme Immobilization Overview

Enzyme immobilization confines enzyme solutions within specific spaces to facilitate reuse in processing equipment.
Various immobilization methods exist, each with unique advantages and disadvantages.

Advantages of Enzyme Immobilization

Reduces operational costs compared to free enzyme systems which require extra separation and purification steps.
Certain immobilization techniques can enhance enzyme activity.
Provides a model system to examine membrane-bound enzyme functions, analogous to those in cellular environments.

Disadvantages of Enzyme Immobilization

Immobilized enzymes often have reduced activity compared to free enzymes.
Preparation costs for immobilized enzymes tend to be higher.
Mass transfer limitations can arise from the immobilization methods used.

Methods of Enzyme Immobilization

Different techniques for immobilization can influence the efficiency and application of enzymes.

Matrix Entrapment

Involves mixing enzyme solutions with semi-permeable polymeric materials that solidify into various forms, such as small beads.
Large molecular weight enzymes remain contained, while smaller substrate and product molecules can diffuse through.
Common entrapment matrices include:
- Ca-alginate
- Agar
- Polyacrylamide
- Collagen

Membrane Entrapment

Enzymes can be confined between thin, semi-permeable membranes made of materials such as:
- Nylon
- Cellulose
- Polysulfone
- Polyacrylate
Hollow fiber configuration is a preferred arrangement for separating enzymes from substrates and products.

Surface Immobilization Methods

Adsorption:
- Enzymes attach to solid supports through weak physical forces, retaining nearly full activity.
- Common support materials include:
  - Alumina
  - Silica
  - Porous glass
  - Ceramics
  - Clay
Covalent Bonding:
- Enzymes are retained on supports via covalent interactions between functional groups on the enzyme and those on the support.
- Key functional groups involved in bonding include amino, carboxyl, hydroxyl, and sulfhydryl groups.
- Covalent bonding must not interfere with the active site; enzyme inhibitors may be added during the bonding process to prevent activity loss.

This quiz focuses on the concepts of enzyme immobilization, including various methods and their industrial significance. After taking this quiz, you'll better understand how enzymes can be contained and reused in processing equipment. Test your knowledge on the different types and advantages of immobilized enzymes.