Learn about the benefits and uses of Bag-On-Valve spray technology.

1. Bag-on-Valve Systems
Creating Barriers
Once a tiny niche of the aerosol market, more and more
Magnus Hedman at
companies are turning to Bag-on-Valve (BoV) aerosols to Aurena Laboratories AB
package their products. BoV is an ideal barrier package
for liquids, gels, creams and lotions, keeping high product
integrity and protection against oxygen exposure
In the pharma industry, there is an
Figure 1: Components for
increased interest in giving old products
BoV with an opened can
new, more convenient applications,
as well as finding niches for totally
new products using Bag-on-Valve
(BoV) technology for packaging and
administration. Applications now cover
saline/seawater nasal sprays, wound
cleansing/irrigation sprays, eyewash
sprays, dermal drug delivery products,
disinfectant sprays and veterinary
products, among others. There is a
slow but growing consumer awareness
regarding BoV products. Global volumes
increase from year to year, replacing
typical pump and dispensing sprays as
well as traditional aerosols.
Diverse Range of Applications
With its many dispensing possibilities,
BoV is suitable for direct dispensing, even
in such sensitive areas as eyes or ears or
with children. After an eye accident, for
instance, it is very important to rinse the
eye in the first seconds. BoV portable eye
Images: Aurena Laboratories AB
wash spray makes a good choice when
a piped eye wash station is not available.
With a 240ml can, equipped with a spray
actuator giving a very soft spray, it is now
possible to flush the eye constantly for
more than 15 minutes.
how long or how often they are used, available for nasal application. In the ear,
Wound washing spray must be kept they are safe for everyone. The saline nose and throat segment there are also
totally sterile during its entire shelf-life, nasal sprays are classified as medical BoV products on the market that help to
which is possible for many BoV products. devices in the EU and can either replace prevent build-up of earwax.
The spray works at any angle, reduces or complement the use of drug-classified
pathogens, removes foreign bodies as nasal sprays. Emollient sprays protect the skin from
well as blood, clot and dead tissue, and minor irritation and soreness and create
moistens the tissue in the process. Another upcoming area currently a barrier that protects irritated skin from
catching interest is that of throat sprays, damage caused by urine and faeces, for
Various nasal sprays are among the most with the aim of soothing and preventing instance. Unlike applying an emollient as
popular BoV products on the over-the- sore throat symptoms during colds a cream and rubbing it onto the skin, an
counter market. Usually based on sterile and allergies. It is possible that we will emollient spray is contact-free, meaning it
saline solutions, they soothe and relieve soon see a similar range of throat spray can be administered without risk of
stuffy noses and sinus pressure. No matter products on the market as is already cross-contamination.
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2. Gels can also be packaged using BoV, 99 per cent, and once the product is used the product, they guarantee its integrity
such as burn gel sprays for treating burns, up and empty, it does not contain any and are not released into the atmosphere.
scalds and sunburns. Creams and foams flammable residual of propellant.
are also suitable solutions to be packaged As the BoV does not use any flammable
in a BoV system, as are alcohol-based Non-Flammable Propellants propellant, it can be classified as a
hand sanitisers. The most common replacements for the non-flammable aerosol, providing the
chlorofluorocarbons, which were used solution itself does not contain flammable
Total Integrity and Sterility as aerosol propellants before they were ingredients. The non-flammable
Taking a look at some of the general banned by the Montreal Protocol in 1989, classification offers obvious advantages
benefits of BoV packaged products are mixtures of volatile hydrocarbons, regarding safety, transportation and
compared to alternative packaging typically propane, n-butane and storage.
solutions, there are a few particularly isobutane. Dimethyl ether and methyl
striking features. First of all, there is the ethyl ether are also used. All these have The foil-based packaging used in a BoV
obvious advantage of total integrity and the disadvantage of being flammable. system typically consists of four-layer
sterility that BoV offers the product sealed aluminium film laminates, for instance
inside the bag. The product will not only Manual pump sprays can be used as polyester, aluminium, polyamide and
be kept sterile until it is used for the first an alternative to a stored propellant. polpypropylen (PET/ALU/OPA/PP), which
time, but will remain sterile during the However, these do have the guarantee impermeability. The film
product’s entire shelf-life. disadvantages of requiring hand power, laminate bag is welded to the aerosol valve,
not providing an even, continuous which is crimped to the aerosol can in the
Then there are the many conveniences dispensing, and normally the inability to filling process. BoV typically uses standard
for the end users of the products, whether use the product at any angle. aerosol cans with one-inch can openings.
they are healthcare professionals or
consumers purchasing the products over The propellants of BoV products, on the When the valve is crimped to the can,
the counter. The fact that they can be other hand, are compressed air or nitrogen, the compressed gas is also filled into the
used at any angle is a great advantage neither of which are flammable or area between the bag and the can. This
compared to hand-pumps or tubes, for hazardous to the environment. Since they pressurising process is called under the
instance, as is the continuous dispensing are contained between the bag and the cup gassing. The process creates an initial
of the products, making them easy to use can, and they never come into contact with pressure of a few bars in the can.
– even in emergency situations.
Figure 2: BoV Technology
Contact-free dispensing gives advantages
in hygiene and patient integrity. Since the
products can be applied without actually
The Valve 1
touching the skin, avoiding the spread of
BoV systems are
contamination from the hands, they are available with both
ideal for sensitive product applications. female and male valves 6 The Actuator
For healthcare professionals and patients A wide range of
alike, it is less encumbering having standard actuators are
The Bag 2 available, depending on
someone spray rather than rub the FDA-approved product demands
content onto the skin. laminated bag
(three or four layers
depending on product
If desired, a BoV aerosol can produce a requirements). Available 5 The Can
smooth and even layer of a film-forming in a wide range of sizes Standard aerosol can,
product or a protective barrier cream aluminium or tinplate.
All sorts of shaped
to the skin. Examples include silicone-
The Product 3 cans can be used. No
based barrier films used for treating dry, limitation in marketing
Suitable for liquid
sensitive skin. Oxygen-sensitive actives as well as viscous
solutions
like probiotics and omega-3 oils are also products, such as
suitable for packaging in BoV systems, gels, creams and
ointments, in a number
even if the commercial products have yet 4 The Propellant
of application areas.
to reach the consumer market. Optimised for oxygen- Because of the
sensitive and sterile separation between
products product and propellant,
Compared to traditional aerosol products BoV can be used with
where the propellant is part of the compressed air or
nitrogen
formula, products dispensed through BoV
have no chilling effect. Product evacuation The Cap
for a BoV product ranges between 95 and Can be used with many kinds of standard overcaps
64 www.samedanltd.com

3. Although the gases used in BoV
Benefits of BoV products are totally harmless, the
products are still classified as aerosols
BoV offers major advantages for a range of • Even and controlled spraying pattern (UN 1950). Depending on the local
aerosol products where safe and contact- for optimal result regulations for aerosols, recycling of
free dispensing is required. BoV gives new • No pumping motion needed BoV products are handled differently in
marketing opportunities through improved • Can be used at all angles
different states or countries. However,
consumer conveniences, product protection • Reduced spray noise
and controlled discharge of the product. • Less chilling product discharge
they usually fit into the recycling
programmes of most countries.
Safety and Environmental Benefits Production and Distribution Benefits Aluminium has a high recycling value
• No need for flammable propellants • Longer shelf-life for oxygen-sensitive and can be recycled many times
• Hygienic and sterilisable products without loss of quality. Still, aerosol cans
• Used with eco-friendly air or nitrogen • Effective filling process
are currently always made of virgin
• Less need for preservatives • Suitable for both liquid and viscous
products aluminium even though they could
Consumer Benefits • Can be used with standard actuators potentially be manufactured from
• Up to 99 per cent product emptying and aerosol cans recycled aluminium instead.
• Longer shelf-life with less preservatives
What the Future Holds
The final pressure, when the product before use, since the bag is fully filled and Ongoing developments of BoV include
has been filled through the valve, is does not allow mixing when shaken. valves where two different mediums
normally between six and nine bars, may be filled, separated from each other
depending on product configuration. The Low Bioburden into a three-chamber-system. Mixing is
product in the bag encompasses 60 per The BoV system can provide effected while spraying or by the user
cent of the can’s brim capacity, while the microbiological safety to the product after application. Another new feature
compressed gas occupies the remaining as it will only come into contact with under development, which will be
40 per cent. the inside barrier film of the bag, and appreciated by the pharma industry, is
as a one-way valve system no metering dosage BoV where dosages like
When pressure-filling the product contamination will come from outside 100µl or 1ml guarantee a certain number
through the valve stem, BoV fillers need the bag. With pre-sterilised bags and of uses for the end consumer, as well as
to be aware of the difference in stem cleanroom production, the bioburden the same product quality from the first
stroke between the various BoV systems of the product can be minimised. dosage to the last.
on the market.
For the pharmaceutical market, the cans In the near future, we can expect new
When choosing a BoV system, the first are most often made of aluminium, even innovative ways to manufacture BoV
step should be to source both the BoV if tinplate BoV systems are also available. with higher speed manufacturing,
system and the spray actuator from the Since gamma rays are able to penetrate laminate developments for more
same supplier to guarantee that the aluminium, the most convenient compatibility and decreasing the
total configuration is compatible. This sterilisation method for BoV products number of laminate layers, as well as
is to avoid micro-leakage and secure is gamma irradiation, although aseptic many other steps in developing the
the correct performance of the product. filling is also sometimes used. For gamma next generation of BoV systems.
Another important factor when using irradiation of products that can
compressed gases is to select a good be classified as sterile, the most About the author
quality aluminium can. common irradiation dose is a
Magnus Hedman is the
minimum of 25kGy, even if lower
Co-Founder, Partner, Marketing
Due to the low permeability rate, BoV is doses are also used. Minimum
Director and Business
compatible with commercially available and maximum irradiation doses Development Manager of Aurena
liquefied propellants. These propellants will need to be validated for Laboratories AB. He is a seasoned
make good choices for products that call each product. The gamma entrepreneur and business
for a steady dispensing rate over the life irradiation process is carried out development specialist who has been involved in
of the can, such as post-foaming gels by sterilisation contractors. Some the medical device and pharma industry for over 20
and creams. gamma irradiation providers years. International Sales and Marketing Manager
offer full pallet sterilisation, for Swedish respiratory care company Aiolos
Almost all fluids and many viscous while sterilisation in ‘tote boxes’ Medical, 1990 to 2000, he co-founded Aurena
products can be filled into a BoV system is most common. In the tote Laboratories in 2000 and has developed a range of
as long as the product’s viscosity is low box irradiator, the product is medical devices in BoV packaging for the pharma
enough to get it through the valve stem. loaded into tote boxes, which industry. Email: magnus@aurena.se
However, the system does not work well are conveyed around the
with products that need to be shaken irradiation source.
66 www.samedanltd.com