Question

Why do lyophilic sols not require any stabilising agent for their preservation?

Answer 1

Lyophilic sols (e.g., sols of starch, gum, gelatin) have a strong affinity for the dispersion medium and are self-stabilised. This is because the particles are heavily hydrated, which prevents them from coming together and settling. As a result, they:

• Do not get precipitated easily, even in the presence of electrolytes.
• Are reversible, meaning if the sol gets dried, it can be reconstituted by simply adding the dispersion medium again.

Therefore, they do not require any external stabilising agent to preserve them.