Week 8 dissolution of solids

Question 1

Dissolution mechanisms

Answer 1

Dissolution of a crystalline solute (drug) is a 3-step process
Step 1: Solute molecule leaves particle
Step 2: Creation of a cavity in the solvent
Step 3: Solute molecule enters the cavity
Boundary region -> solvent around the drug crystal, will become quite saturated with drug molecules
Boundary layer - (h) is a thin layer of solvent molecules that surround the solute