Formulation and Manufacturing of Aerosols and their Evaluation

1. Pharmaceutical Aerosols
their
Formulation and
~ Anurag Gupta

2. Outlines
1 2 3 5 6
4
Aerosols
Component
of
Aerosols
Types of Aerosol System
Formulation
of
Aerosols
Manufacturing
Evaluation

3. Aerosols
Aerosol is a pressurized dosage forms containing
one or more therapeutic active ingredients which
upon actuation emit a fine dispersion of liquid or
solid materials .

4. Principle
Aerosol system are composed of two components i.e. product
concentrate and propellant .
Upon actuation of the aerosol valve, the pressure built up by the
vaporized propellant pushes the liquid phase up in the dip tube and out
of the container.
The expelled contents are exposed to the atmosphere
 As a result, the propellant present in these contents expands and
evaporates due to the sudden drop in pressure, leaving behind the
product concentrate as airborne liquid droplets or dry particles.

5. Advantage
Easy to carry and convenient to use.
Onset of action is quick.
The products are protected from light and oxidation ,
hence stability is increased.
It is clean process to as it requires no wash-up.
The desired dose can be removed.

6. Disadvantage
It is expensive
Irritation may occur upon topical administration of aerosol
Valve clogging may takes place

7. COMPONENTS OF AEROSOLS
Valve and actuator
Propellant
Container
Product concentrate

8. PROPELLANTS
Propellant are the important constituents of an aerosol
formulation.
It Responsible for developing proper pressure within the
container.
Provide driving force to expel the product from the
container in the form of a fine spray or foam through the
valve.

9. TYPES OF PROPELLANTS
1)Liquefied gases Propellants
e.g. Chlorofluorocarbon , Hydrofluorocarbon
2)Compressed gases Propellants
e.g. Nitrogen ,carbon-dioxide , nitrous oxide

10. CONTAINERS
Containers are used to fill the aerosols. Usually, aerosol spray
containers are primarily made up of metal, glass, plastics depend
on the behavior and characteristic of solvent and propellant used.
For the aerosol , the container material should be enough to
withstand pressures as high as 140 to 180 psig (pounds per sq.
inch gauge) at 130 ° F.

11. VALVES
A valve is an important part of aerosol containers.
It helps in expelling the contents from the container in the desired form, at
the desired rate and in the desired amount .
The performance of an aerosol depends on the type of formulation and
valve. They help in preventing the loss of product when the container is not
in use.
The materials used in the manufacture of valve should be inert to the
formulation.

12. Components of Valves

13. Actuators
 Actuator is an integral part of an aerosol package.
It is a specially designed button placed on the valve stem which
helps in easy opening and closing of the valve and aids in rapid
and proper release of the products from the container.
It also helps in delivering the product in the desired form i.e.,
spray, wet stream, foam or solid stream.

14. TYPES OF AEROSOL SYSTEMS
 Solution system
 Water based system
 Suspension or Dispersion systems
 Foam systems
 Intranasal aerosols
Aerosols are classified as follows :

15. FORMULATION OF AEROSOLS
It consist of two essential components :
i.e. Product concentrate and Propellant
Product concentrate : Active ingredient or mixture of active
ingredients and other necessary agents
such as solvents, anti oxidants and surfactants.
Propellant : Single or mixture of various propellants is used.
The propellant are selected on the basis of desired
vapour-pressure , particle size and solubility
characteristics .

16. Manufacturing of Pharmaceutical Aerosols Apparatus
Pressure filling apparatus Cold filling apparatus
Compressed gas filling apparatus

17. Evaluation
Flammability
&
combustibility
Physio-
chemical
Performance Biological
Flash point
Flame
Extension
Vapor
pressure
Density
Moisture
Aerosol valve
discharge rate
Spray pattern
Net contents
Foam stability
Particle size determination
Therapeutic
Activity
Toxicity

18. Cyanide