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Assignment Pharmaceutical Aerosols
Assignment
(Pharmaceutical Aerosols)
Muhammad Kafeel
Roll No. 107 (Batch II)
Pharmaceutics
Sir. Shoaib Hakeem
M.Kafeel Roll No. 107 |
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Assignment Pharmaceutical Aerosols
Pharmaceutical Aerosols
Aerosol is pressurized dosage form in which therapeutically active drug is dissolved or dispersed or suspended in compressed or liquefied gas
to expel the content from the container in the form of spray.
Aerosol mainly used for the treatment of Asthma and COPD disease etc.
Aerosols are used for topical, oral or nasal administration in the form fine particles or mist or fog.
In mid 1950 the pharmaceutical aerosol introduced in market.
Types of Aerosols
There are three types of aerosol spray.
Space sprays.
Surface coating spray.
Foam spray.
1. Space Spray:
These products are delivered as a fine mist is called space spray .It contains 85% propellant and it is pressurized at 700F
with 30-40 psig. It contains not more than 50 μm of particle. So it can be retain in air. E.g. Room sprays.
2. Surface Sprays:
Aerosols intended for carrying active ingredients to surface are termed as surface sprays or surface coating spray. It
contains 30 –70% propellant operates between 22–55 psig at 700F. E.g. Topical Aerosol.
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Assignment Pharmaceutical Aerosols
3. Foam Spray:
Foam aerosols (emulsion) usually operate between 35 and 55 psig at 21°c and contains only 6-10% propellant.
Design of Aerosol Containers
They must be stand at pressure as high as 140 to 180 psig (pounds per sq. inch gauge) at 1300 F. They are of following types;
1. Tin plate containers:
They consist of sheet of steel plate that has been electroplated on both sides with tin.
2. Aluminum containers:
Greater resistance to corrosion.
Light weight, not fragile.
Good for light sensitive drugs.
3. Stain Less Steel Containers:
Limited for smaller size.
Extremely strong and resistant to most materials.
Pressure stand.
4. Glass Containers:
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 drugs.
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Assignment Pharmaceutical Aerosols
Component of Aerosols
Actuator
Ferrule or mount cup
Valve body or housing
Stem valve
Gasket
Spring
Dip tube
Actuators:
These are specially designed button placed on the valve system which helps in easy opening and closing of the valve. It
helps in deliver the product in the desired form. There are different type of actuators are used,
Spray Actuators
Foam Actuators
Solid Stream Actuators
Special Actuators
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Assignment Pharmaceutical Aerosols
Ferrule or Mount Cup:
It is used to attach the valve in proper position in container.
It is necessary coated with epoxy resin.
Valve:
Regulate the flow of product and discharge the content. Valve is associated with the help of
actuator (if the foam present in the container) to emitted the product as wet or spray.
Valve body or Housing:
It is made of nylon/delrin and contains at the opening point of dip tube (0.013 to 0.080 inch).
It prevents clogging of particle size; reduce chilling effect of the skin.
Stem:
It is made of nylon /delrin or stainless steel. It contains one or more orifice (0.013 to 0.030).
Gasket:
It is made of Buna –N, Neoprene rubber.
Spring:
It is used to hold the gasket in a place and when actuator is depressed it returns the valve in closed position.
It is made of stainless steel.
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Assignment Pharmaceutical Aerosols
Dip Tube:
It is made up of poly propylene material / poly ethylene. Inside diameter (0.120 – 0.125).
Formulation of Aerosols
Aerosols consist of
Product concentrate
Propellant
1. Product Concentrate:
Product concentrate consist of API, Additives like suspending agent , emulsifying agent , antioxidant,
aqueous and non aqueous ,co-solvent etc.
2. Propellant:
It is responsible for developing the vapor pressure with in the container and also expel the product when the valve is opened and in the
atomization or foam production of the product.
It is classified in to mainly two types
1. Liquefied gas system
2. Compressed gas system
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Assignment Pharmaceutical Aerosols
a. Liquefied Gas System:
These compounds are gases at room temperature and atmospheric pressure .However they can be liquefied easily by lowering the
temperature (below the boiling point or by increasing pressure). These compounds are chosen generally have boiling point below 700F and
vapor pressure between 14 and 85 psia at 700 F. When it is placed into sealed container it immediately separates into a liquid and a vapor
phase. Examples are;
Fluorinated Hydrocarbons: These include tri-chloro-mono-flouro-methane, Di-chloro-di-fluoro-methane, Di-fluro-ethane. These are
used for oral and inhalation aerosol preparation.
CHLORO FLURO CARBON (CFC): These include Hydro-chloro-carbon, Hydro-fluro-carbon, hydro-chloro-fluro-carbon.
Hydrocarbons: These include Butane, Isobutane, and Propane. These are mainly used for the preparation of topical preparation.
b. Compressed Gas System:
Compressed rather than liquefied gasses may be used to prepare aerosols. The pressure of the
compress gas in the head space of the aerosol container forces the product concentrate up the dip tube and out of the valve. The use of gasses
that are insoluble in the product concentrate, as is nitrogen will result in emission of product in essentially the same form as it was place in the
container.
Types of Aerosol System
There are five types of aerosol system;
Solution system / Two phase system
Water based system / Three phase system
Suspension or Dispersion system
Intranasal foam
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Assignment Pharmaceutical Aerosols
1. Solution System:
This consists of two phases: a vapor phase and a liquid phase. Propellant has high pressure hence
propellant 114 is added to reduce its vapor pressure.
2. Water Based System:
It is three phase system containing vapors phase, propellant and water. Ethanol is used as a co-solvent to solubilize the propellant in water.
Propellant content varies from 25 -60%.
3. Suspension System:
It is prepared by dispersion active ingredients in mixture propellant and by using suspending agent. The physical stability of suspension can be
increased by use minimum solubility of API. E.g. Ephedrine bi-tartarate is less soluble than Hcl. By Use of surfactant to reduce the
agglomeration E.g. Sorbitan monolaurate ,sorbitan monooleate sorbitan trioleate, isopropyl myristae.
4. Foam System:
They contain Dispersion of Vehicle, surfactant and propellant. Liquefied propellant used as internal phase.
Aqueous stable foam:
Ingredients are oil waxes, O/W surfactant, water and hydrocarbon.
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 in to liquid. Useful for topical medication.
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Assignment Pharmaceutical Aerosols
Types of Aerosols Delivery
1. Nebulizers:
It is a device used to converting a liquid drug (Solution /suspension) into a fine mist which can
then be inhaled easily. It used to administer medication to people in the form of a mist inhaled
into the lungs.
E.g. Jet Nebulizer (air jet /air blast), Ultrasonic Nebulizer.
2. Meter dose Inhaler (MDI):
It pressurized, hand-held devices that use propellants to deliver doses of medication to the lungs of
a patient Propellant driven aqueous pump sprays.
Metered-dose inhalers (MDIs), introduced in the mid 1950. In MDIs, drug is either dissolved or suspended in a liquid
propellant mixture together with other excipients, including surfactants and presented in a pressurized canister fitted with
a metering valve. A Predetermined dose is release when up on actuation.
3. Dry powder inhaler (DPI):
It delivers medication to the lungs in the form of a dry powder. In DPI the drug is
inhaled as a cloud of fine particle. The drug is either preloaded in the inhaled device or filled in hard
gelatin capsule.
DPI is propellant free. No additive except carrier like lactose. It can deliver large dose than MDI
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Assignment Pharmaceutical Aerosols
Advantages of Aerosols
It produces Rapid action.
It is suitable for when the degrade in GI tract.
It directly applied to the affected area.
It Prevents to Oxidation of drugs.
It can avoid the hepatic metabolism of drugs.
It can be maintain sterility & easy to portable.
It produces local & systemic effect (due to large surface area of lung and blood capillary).
Disadvantages of Aerosols
Limited safety hazard (Flammable Nature).
It is a Costly Preparation.
It is a chance for continuous deposition of particle in upper respiratory tract.
The propellant may cause chillness to the skin.
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