Learning Objective

• Physical, chemical and biological parameters for evaluating aerosols

Pharmaceutical aerosols can be evaluated by the following series of physical, chemical and biological tests:

1. Flammability and combustibility
   1. Flame extension or projection
   2. Flash point
2. Physicochemical characteristics
   1. Vapor pressure
   2. Density
   3. Moisture content
   4. Qualitative and quantitative tests for propellants
3. Performance characteristics
   1. Aerosol valve discharge rate
   2. Spray pattern
   3. Dosage with metered valves
   4. Net contents
   5. Foam stability
   6. Particle size determination
   7. Leakage
4. Biological testing
   1. Therapeutic efficiency
   2. Toxicity