An ampoule is a small sealed vial which is used to contain and preserve a
sample, usually a solid or liquid. Ampoules are commonly made of glass,
although plastic ampoules do exist. Modern ampoules are most commonly used
to contain pharmaceuticals and chemicals that must be protected from air and
contaminants. They are hermetically sealed by melting the thin top with an
open flame, and usually opened by snapping off the neck. If properly done,
this last operation creates a clean break without any extra glass shards or
slivers; but the liquid or solution may be filtered for greater assurance. The
space above the chemical may be filled with an inert gas before sealing. The
walls of glass ampoules are usually sufficiently strong to be brought into a
glovebox without any difficulty. Glass ampoules are more expensive than
bottles and other simple containers, but there are many situations where their
superior imperviousness to gases and liquids and all-glass interior surface
are worth the extra cost. Examples of chemicals sold in ampoules are
injectable pharmaceuticals, air-sensitive reagents like
etrakis(triphenylphosphine)palladium(0), hygroscopic materials like deuterated
solvents and trifluoromethanesulfonic acid, and analytical standards.
Historic ampoules Historically ampoules were used to
contain a small sample of a person's blood after death, which was entombed
alongside them in many Christian catacombs. It was originally believed
that only martyrs were given this burial treatment, though it is suspected to
have been a widely-practiced tradition. = San Gennaro=
An ampoule, allegedly dating back to the year 305 and filled with the blood of
Saint Januarius, bishop of Benevento, has been kept for centuries in the
Cathedral at Naples. Every year on the 19th of September the town celebrates
the Feast of San Gennaro, when the solid reddish-brown contents of the ampoule
usually liquifies after being taken out of a safe, carried in procession and
placed on the Cathedral's altar. = Sainte Ampoule=
Another well known ampoule is the Holy Ampulla which held the anointing oil for
the coronation of the French monarchs. The oil was allegedly passed down from
the time of Clovis I; it was kept for a time in the tomb of Saint Remigius and
later in the Cathedral of Notre-Dame, Reims. An order of knights named after
the ampoule was created for the coronation of kings to have been saved
and was used in coronation of Charles X. Production
Modern glass ampoules are produced industrially from short lengths of glass
tubing, shaped by heating with gas torches and gravity in automated
production lines. Computer vision techniques are usually employed for
quality control. The filling and sealing of ampoules may
be done by automated machinery on an industrial scale, or by hand in
small-scale industries and laboratory settings. Blank ampoules can be
purchased from scientific glass supply houses and sealed with a small gas
torch. This forms a membrane allowing someone to turn the open ampule upside
down without spilling. A Schlenk line may be used for sealing under inert
atmospheres. Other uses
Ampoules are common practice as containers of low frequency RFID tags.
These are used mainly for tagging animals, such as dogs for
identification. Ampoule codes
Ampoules often have colored rings of paint or enamel around their necks.
Color coding of modern ampoules is done during the manufacturing process. A
machine paints colored rings on the ampoule shortly after it has been
sealed. The rings are made of a substance that is readable by other
machines. These color codes identify the substance inside the ampoule so that it
does not need to be tested to verify the contents. The machine-readable color
codes allow for accurate handling of the substance for the purposes of storage,
labeling, and secondary packaging. The dot above the neck identifies the
location of a small cut in the glass to help breaking/opening the ampoule.
See also Ampulla
References Hans-Jürgen Bässler und Frank Lehmann :
Containment Technology: Progress in the Pharmaceutical and Food Processing
Industry. Springer, Berlin 2013, ISBN 978-3642392917