The physical and chemical properties of protein play an important role in the process of separation and purification. Solubility: protein has different solubility in different solvents, which provides a basis for separation and purification. Generally, the solubility of protein in polar solvents such as water is greater than that in nonpolar solvents such as organic solvents.

1, use this property.

Using this characteristic, protein can be extracted from the mixture by choosing a suitable solvent. Molecular weight and molecular weight distribution: The molecular weight and molecular weight distribution of protein are important factors to determine its physical and chemical properties. Protein can be separated and purified by gel chromatography according to its molecular weight and molecular weight distribution.

2. Using different protein molecular weights.

These methods utilize the speed difference of different protein molecular weights through a specific pore size to realize the separation of different protein. Isoelectric point: protein has different charge properties at different pH values. The isoelectric point is the pH value when all charges in protein molecules cancel each other and the molecules are electrically neutral.

3. Use the difference of isoelectric point

According to the different isoelectric points, we can choose a buffer with appropriate pH value for electrophoresis or ion exchange chromatography to separate different protein. Hydrophobicity: The hydrophobicity of protein is closely related to its structure and function. Hydrophobicity refers to the interaction between protein and water molecules.

4. Reversed-phase chromatography can be used.

Using this characteristic, protein can be separated and purified by reversed-phase chromatography and hydrophobic interaction chromatography. These methods utilize the difference of interaction force between different protein and nonpolar solvents to realize the separation of different protein. Conformation and secondary structure: protein's conformation and secondary structure determine its function and stability.

5. By X-ray diffraction

The conformation and secondary structure of protein can be studied by X-ray diffraction and infrared spectrum. These methods utilize the differences of different protein conformations and secondary structures to separate and purify different protein. Enzyme activity: Many protein have enzyme activity, which makes them play an important catalytic role in organisms.