Penn-Century MSA-250-M for Mouse - Manual (Page 6)

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Determining the optimal dose range
· Direct aerosol administration to the lungs with a Penn-Century intratrachael device permits far
more precise quantification of the delivered dose and far higher drug concentration than is
possible with large nebulizer or exposure systems for animals that mix drug with compressed air
that is blown - at high momentum - at the nose of the animal. The aerosol from the
MicroSprayer® Aerosolizer is gentle, air-free, low momentum, highly concentrated and precisely
quantifiable.
· A review of literature citing Penn-Century devices indicates that they permit far more efficient
administration of very small doses, as well as the ability to deliver far larger doses volumes than
would be possible by animal nebulization/exposure/inhalation systems and more far more safely
than liquid bolus/droplet instillation through a gavage needle, catheter or endotracheal tube.
· Researchers should take into consideration that the optimal, most effective dose
range they can administer using a Penn-Century intratracheal drug delivery device
may be an amount that is far smaller or far larger than is possible within the
limitations of standard methods of pulmonary drug delivery in animal models. The
user must conduct feasibility experiments to determine the optimal dose for their own
formulation by increasing the dose in small increments to determine the minimum or maximum
effective dose, and to plan for this process in their experimental design.
Determining deposition
· Use of all Penn-Century devices for intratracheal applications is essentially a form of
intubation. The user must insert the tip of the device gently down the trachea of the
anesthetized animal, near to but not touching the carina. Particularly when working with small
animals such as mice, some users may wish to practice on several test animals by spraying
with dye or a fluorescent or radio-opaque contrast agent to determine if the tip of the
MicroSprayer® Aerosolizer was correctly positioned, and to determine if the test liquid was
well-distributed in the lungs, or was mostly deposited in the trachea or swallowed. Penn-
Century also makes several helpful accessories, including a Small Animal Laryngoscope and a
Mouse Intubation Platform to help users quickly and easily visualize the epiglottis and correctly
insert the tip of the MicroSprayer® Aerosolizer for optimal results.
· Practice with dye or contrast materials: Some users have found it helpful when learning to
correctly use the MicroSprayer® Aerosolizer to practice with radio-opaque materials, such as
Technicium 99m, fluorescent materials or dyes, such as Methylene blue dye or Evans blue dye.
(We strongly discourage using India ink for this purpose, as it may contain carbon particulates
or shellac that can clog the sprayer tip over time.)