Acid-Base Properties of Amino Acids
Denaturing and Precipitating Proteins
Enzymatic Activity of Glucose Oxidase
HIV-1 Protease: An Enzyme at Work
Studying Enzyme Kinetics Using Catalase
Binding of Coomassie Brilliant Blue to Egg Albumin
Breaking Down Sucrose Using Invertase
Color Reactions of Amino Acids
Effect of pH on Protein Solubility
Enzyme Catalyzed Decomposition of Hydrogen Peroxide
Enzyme Kinetics: Experiments With Catalase Extract
Halting the Briggs-Rauscher Reaction
Hydrolysis of Wool in Strong Base
Effect of pH on Protein Solubility
Description: Casein dissolves in an aqueous base. When acid is added to the solution slowly, the protein precipitates but dissolves in excess acid. The process may be reversed by adding base to the acidic solution.
Source: Shakhashiri, B.Z. Chemical Demonstrations: A Handbook for Teachers of Chemistry
Year: 1989 Vol: 3 Page: 188
Keywords: pH, Protein, Casein, Solubility of proteins
Rating: 
Hazard: Some
- Acute toxicity hazard
- Skin corrosion hazard
- Inhalation hazard
- Serious eye damage
- Corrosive to metals
Effectiveness: Good
- Results are observable without guidance
- Good connection from demo to course material
- High reliability
- Time to results is low
Difficulty: Medium
- Use of reactive substances
- Some sequential manipulations
- Some timed manipulations
- Sequential procedures
Safety Precautions:
- Eye protection required
- Gloves required
- UL approved three-prong plug and outlet if required
- Absorbent material on hand
- Sodium bicarbonate on hand
Class: Biochemistry, Acid Base Chemistry, Solubility
Division: General, Biological Chemistry
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