3. Contents:
aerosols
history
Advantages and disadvantages
Components of aerosols
formulation
Preparation and filling
Types of aerosols spray
Packaging storage and labeling
4. Aerosols:
“A system that depends on the power of
a compressed gas or liquefied gas to
expel the contents from the container.”
Pharmaceutical aerosols:
Aerosol product containing active
ingredients dissolved ,suspended or
emulsified in a propellant or a mixture of
solvent and propellant and intended for oral
or topical administration or for
administration into the eye, nose ,ear,
rectum and vagina.
5. History of aerosols
The concept of an aerosol originated as
early as 1790, when self-pressurized
carbonated beverages were introduced in
France.
on 1927, Norwegian engineer Erik
Rotheim patented the first aerosol can
and valve that could hold and dispense
products and propellant systems.
During World War II, Lyle Goodhue
and William Sullivan, developed a small
aerosol can pressurized by a liquefied
gas (a fluorocarbon) in 1943.
6. Cont…
In 1949, 27-year-old Robert H.
Abplanalp’s invention of a crimp on valve
enabled liquids to be sprayed from a can
under the pressure of an inert gas. Spray
cans, mainly containing insecticides, were
available to the public in 1947 as a result
of their use by U.S. soldiers for preventing
insect-borne diseases.
Abplanalp’s invention made of
lightweight aluminum made the cans a
cheap and practical way to dispense
liquids foams, powders, and creams.
7. Advantages of aerosols
Pulmonary Therapeutics.
First Aid.
No More Bug Bites.
Breathe Easy.
Right On Target.
No Mess.
Safety .
Child Resistant.
8. DISADVANTAGES:
Limited safety hazard (Flammable
Nature)
It is a costly preparation
Expensive Catalytic oxidation of drugs.
e.g. Ascorbic acid and Epinephrine
It is a chance for continuous deposition
of particle in upper respiratory tract
The propellant may cause chillness to the
skin, Discomfort on injured skin
Chlorofluorocarbon propellants cause
Ozone layer depletion
9. Qc testing for aerosols:
1. Physical & chemical inspection
of the valves, actuators and dip
tubes.
2. Specifications of propellants
3. Containers should be chesked
for conuctivity, flaws, weight and
dimensiond
4. Leak testing
5. Spray testing
12. Propellant:
It is responsible for developing the vapor
pressure within the container and also
expel the product when the valve is
opened foam production of the product.
Liquefied gas propellants:
Liquefied propellants are gases that exist
as liquids under pressure.
14. Containers:
They must be able to with stand pressures as high as 140 to 180 psig (pounds
per sq. inch gauge) at 130 ° F.
1. Tin Plate container: Consist of sheet of that has been
electroplated on both sides with tin.
2.Aluminum Containers:
Greater resistance to corrosion
Light weight
Good for light sensitive drugs.
15. 3. Stainless Steel Container:
Limited for smaller size
Extremely strong and resistant to moist
materials
Pressure stand
4. Glass Container:
Available with plastic or without plastic
coating
Compatible with many additives
No corrosion problems
Can have various shape because of
molding
Not for light sensitive drug
16. Valve:
Capable of delivering the content in the
desired form such as spray, foam, solid
stream etc.
TYPES OF VALVES :
1. Continuous spray valve - for topical aerosols
2. Metering valve
17. Valve assembly
Valves assembly consists:
• Ferrule or mounting cup- attach valve to
container
• Valve body or housing- contains a
opening at the point of attachment of dip
tube.
• Stem
• Dip tube
• Gasket
• Spring
METERING VALVES: Used for dispensing
of potent medication .Operates on the
principle of a chamber whose size
determines the amount of medication
dispensed.
18. ACTUATORS:
These are specially designed buttons which helps in delivering
the drug in desired form i.e., spray, wet stream ,foam or solid
stream .
TYPES OF ACTUATORS:
• Spray actuators - used for topical preparation. It
allows the stream of product concentrate and
propellant to pass through various openings and
dispense as spray.
• Foam actuators - consist of large orifice
• Solid steam actuators - required for dispensing
semi solid products such as ointments .
• Special actuators - used for a specific purpose. It
delivers the medicament to the appropriate site of
action
19.
20. Formulation consists of two essential components:
1. Product concentrate
2. Propellant
PRODUCT CONCENTRATE:
Active ingredient or mixture of active ingredients and other
necessary agents such as solvents, anti oxidants and
surfactants.
PROPELLANT:
Single or blend of various propellants is used. Blend of
solvents is used to achieve desired solubility
characteristics.
Various surfactants are mixed to give the proper HLB value
for emulsion system. The propellants are selected to give
the desired vapor pressure, solubility and particle size.
Type of system selected depends on
1. Physical, chemical and pharmacological properties of
drug.
2. Site of application
21. TYPES of AEROSOL
SYSTEMS:
• Solutionsystem
• Water based system
• Suspension or Dispersion systems
• Intranasal aerosols
• Foam systems
1. Aqueous stable foams
2. Non aqueous stable foams
3. Quick-breaking foams
4. Thermal foams
22. SOLUTION SYSTEM
This system is also referred to as two phase system consists of
vapor and liquid phase. If active ingredient is soluble in
propellant, no other solvent is required
WATER BASED SYSTEM
Large amounts of water can be used to replace all or part of the non
aqueous solvents used in aerosols. Produce spray or foam. To produce
spray, formulation must consist of dispersion of active ingredients and
other solvents in emulsion system in which the propellant is in the
external phase.
23. FOAM SYSTEM :
They contain Dispersion of AI, aqueous vehicle, surfactant and propellant.
Liquefied propellant used as internal phase.
•Aqueous stable foam : Active Ingredients (antiseptic),
oil waxes O/W surfactant, Water and Hydrocarbon
propellant
•Non aqueous stable foam: These are prepared by using
Glycols Emulsifying agent used this type PEG Esters
•Quick breaking foam: The product is dispensed as foam
which then collapsed into liquid. Useful for topical
medication.
•Thermal foams: Used for shaving
24. INTRANASAL AEROSOLS :
Intended to deposit medication into nasal passages for local or
systemic effect. Advantages: Deliver measured dose of drug.
34. It consists of a pressure burette
capable of metering small
volumes of liquefied gas into the
aerosol container under
pressure.
PRESSURE BURETTE
35. • Solutions, emulsions,
suspensions can be filled by this
method as chilling does not occur.
• Contamination due to moisture
is less.
• High production speed can
be achieved.
• Loss of propellant is less.
36. • Certain types of metering
valves can be handled only
by the cold filling process.
• Process is slower than
cold filling method.
37. It consist of an insulated box fitted with
copper tubing & the tubings are coiled
to increase the area exposed to cooling.
38. • Easy process .
• Aqueous products,
emulsions & those products
adversely affected by cold
temperature cannot be filled
by this method.
39. Compressed gases have high pressure hence a
pressure reducing valve is required.
The apparatus consists of delivery
gauge.
40.
41. TYPES OF AEROSOLS SYSTEM
1) Solution system / Two phase
system
2) Water based system / three phase
system
3) Compressed Gas System
42. SOLUTION SYSTEM
Or
TWO PHASE SYSTEM
Simplest system
The two phases are:
Liquid phase (liquefied propellant & product concentrate)
Vapor phase
Product concentrate is dissolved or dispersed in liquefied
propellants and solvents creating a homogenous system
Propellants exist in both Liquefied phase & Vapor phase
On activation of valve, pressure of vapor phase causes
liquid phase to rise in dip tube and expelled from the
container.
43. THREE PHASE SYSTEMS
The three phases are:
1) A layer of water-immiscible liquid propellant
2) A layer of highly aqueous product concentrate
3) A vapor phase
This type of system is used when formulation
requires the presence of a liquid
phase that is not propellant miscible.
When aerosol valve is actuated, the pressure of
vapor phase causes the liquid phase to rise in the
dip tube and be expelled from the container
because liquefied propellant has greater density
than aqueous layer.
It generally resides at the bottom of container with
the aqueous phase floating above it.
44. COMPRESSED GAS SYSTEM
Compressed gas other than liquefied gases may be used to
prepare aerosols.
The pressure of the compressed gas in the head space of aerosol
container forces the product concentrate up the dip tube and out of the
valve.
Gases used are insoluble in product concentrate. Like nitrogen.
It results in emission of a product that is essentially in the same form as
it was placed in the container.
Compressed gas-filled aerosols have no reservoir of propellant.
Higher gas pressures are required in these systems, and pressure in
these aerosols diminishes as the product is used.
45. TYPES OF AEROSOLS SPRAY
There are 3 types of Aerosol Sprays:
1. Space sprays
2. Surface coating spray
3. Foam spray
46. 1) SPACE SPRAY: 2) SURFACE COATING SPRAY:
• Its products are delivered in a fine • Aerosols intended for carrying active
mist ingredients to surface are termed as
surface sprays or surface coating
• It contains 85% propellant and it is spray.
pressurized at 30-40psi and 70 °F
• It contains not more than 50µm of
particle. So it can be retaining in air.
• Example: Room Sprays • It contains 30 –70% propellant
operates between 22–55 psig at 70F.
• E.g. Topical Aerosol
3) FOAM SPRAY:
Foam aerosols (emulsion)
usually operate between 35
and 55 psi at21°c and contains
only 6-10% propellant
48. • Pharmaceutical aerosols compared to other dosage forms is that the
product is actually packaged as part of the manufacturing process.
• Most aerosol products have a protective cap or cover that fits snugly over
the valve and mounting cup. This protects the valve against contamination
with dust and dirt.
The cap, which is generally made of plastic or metal, also serves a
decorative function.
• Aerosols should be maintained with the protective caps in place to
prevent accidental activation of the valve assembly or contamination by
dust and other foreign materials.
49. LABELLING & STORAGE OF AEROSOLS
Medicinal aerosols that are to be dispensed only
upon prescription are labeled by the manufacturer
with plastic peel-away labels or easily removed paper
labels so that the pharmacist may easily replace the
manufacturer’s label.
An aerosol required to be labeled "Flammable“
Safety labels must warn users not to puncture
pressurized containers, not to use or store them near
heat or an open flame, and not to incinerate them.
Name and address or trade mark of the person
responsible for marketing the aerosol dispenser.
There are now only two classes for flammability –
‘flammable’ and ‘extremely flammable’) it is now
required to be marked with the ‘flame symbol’ in
addition to marking it with the words ‘flammable’ .
50. STORAGE OF AEROSOLS
Exposure to temperatures above 49°C
(120°F) may burst an aerosol container.
When the containers are cold, less than
the usual spray may result.
This may be particularly important to users
of metered-dose inhalation sprays.
They are generally recommended for
storage between 15°C and 30°C (59°F and
86°F).
