This document discusses aerosols and inhalers. It defines aerosols as fine dispersions of liquid or solid particles in a gas. Aerosols can be natural or man-made. The key components of aerosols include the propellant, product concentrate, container, and actuator/valves. The document explains that gases can be liquefied under high pressure and revert to gas when pressure is reduced, which is the principle behind aerosol preparation. It notes that inhalers deliver medicine through inhalation and come in metered-dose, dry powder, and nebulizer forms.

1. IIIrd Semesester B. pharmacy
Physical Pharmaceutics-I
Unit-II
State of matter and properties
of matter (Part-5)
(Aeresols, Liquification of gases, Inhaler)
Miss. Pooja D. Bhandare
(Assistant professor)
Kandhar college of pharmacy

2. AEROSOLS
• Definition : “aerosols is a pressurized dosage forms containing one or
more therapeutic active ingredient which upon actuation emit a fine
dispersion of liquid and/ or solid materials in a gaseous medium”
• An aerosols is a suspension of fine solid particles or liquid droplet, in air
or another gas.
• Aerosols can be
1. Natural: fog, dust, forest exudates and geyser steam
2. Anthropogenic: haze, particulate air pollutants and smoke.

3. PRINCIPLE:
•Gases can be liquefied under high pressure in closed
chamber as the chamber is maintained below the critical
temperature.
•When the pressure is reduced, the molecules expand and the
liquid reverts to a gas.
•This reversible change of state is the basic principle
involved in the preparation of pharmaceutical aerosols.

4. COMPONENTS OF AEROSOLS:
Aerosols
Propellant Product concentrate
Contain
er
Actuator
Valves

5. • In such products, a drug is dissolved or suspended in a propellant, a
material that is liquid under the pressure conditions existing inside the
container but that forms a gas under normal atmospheric conditions.
• The container is so designed that, by depressing a valve, some of the drug-
propellant mixture is expelled owing to the excess pressure inside the
container.
• If the drug is non volatile, it forms a fine spray as it leaves the valve
orifice; at the same time, the liquid propellant vaporizes off.

6.  LIQUEFACTION OF GASES
1. GASES can be liquified under high pressure n a closed chamber as long
as the chamber is maintained below the critical temperature.
2. When the pressure is reduced, the molecules expand and the liquid reverts
to a gas.
3. This reversible changes of state is the basic principle involved n the
preparation of the pharmaceutical aerosols

7. 4. In such products, a drug is dissolved or
suspended in a propellant, a material that s liquid
under the pressure conditions existing inside the
container but that forms a gas under normal
atmospheric conditions.
5. The container is so designed that, by depressing a
valve, some of the drug propellant mixture is
expelled owing to the excess pressure inside the
container.
6. If the drug is non volatile, it forms a fine spray as
it leaves the valve orifice, at the same time, the
liquid propellant vaporizes off

8.  INHALER
• An inhaler is a drive holding a medicine that you take by breathing in
(Inhaling).
• Inhalers are often used to treat chronic obstructive pulmonary disease
(copd).
• There are three types:
1. Metered-dose inhaler
2. Dry inhaler
3. Nebulizers

9. Thank
you!