Penn-Century MSA-250-M for Mouse - Manual (Page 10)

10
Removing air bubbles from the syringe.
The Penn-Century MicroSprayer® Aerosolizer is an air-free aerosol system. Air bubbles may on
occasion become attracted to the hydrophobic Teflon® tip of the plunger in the FMJ-250 syringe while
you are filling it – causing the quality of the spray to degrade. You may observe tiny lines or streams of
liquid in it. In order to deliver discrete sprays of small doses (no streaming at the beginning or end of
the spray cycle), the FMJ-250 syringe must be completely free of air bubbles. This can be determined
by testing the device before use with water or with the solution to be used. If the spray quality
indicates the presence of air bubbles, they can be eliminated by using the special Air Purge Kit provided.
This kit has a soft tip that will not scratch the Teflon™ tip of the plunger.
• Purging air from the syringe: Be sure all liquid is removed from the empty syringe barrel before
proceeding. This can be accomplished by removing the plunger and blowing a small amount of
compressed air through the FMJ-250 Syringe. It should be possible to see clearly from one end to
the other when holding it to the light.
· Find and fill your Air Purge Kit. Attach the special plastic (polypropylene) dispensing tip (red plastic)
to the plastic 1 cc syringe and fill the assembly with test formula or water, being sure to eliminate all
air bubbles from the plastic syringe. Remove the MicroSprayer® Aerosolizer from the FMJ-250
Syringe, and pull back the plunger to a distance about equal to the length of the white dispensing
tip. Insert the white dispensing tip into the open end of the FMJ-250 syringe until the needle
touches the Teflon® plunger tip. Then begin to fill the FMJ-250 Syringe from the plastic syringe, as
shown (above right) while slowly withdrawing the plastic syringe. Continue to push on the plastic
syringe as the needle is withdrawn, so that by the time the white dispensing tip is almost completely
removed, you see a bulge of excess water has formed at the distal tip of the FMJ-250 Syringe. Be
sure to fill the FMJ-250 Syringe with sufficient liquid so that there are no air pockets when the
plunger is pushed in. Now, set aside the plastic Air Purge syringe, and immerse the distal tip of the
FMJ-250 Syringe the solution to be administered
and fill the syringe to capacity. Attach the
MicroSprayer® Aerosolizer and the system is ready to operate.
• Another very effective way to rid the system of air bubbles is to remove the plunger from the FMJ-
250 barrel and, using the Air Purge syringe/needle (or similar arrangement), inject liquid into top or
(proximal end) of the FMJ-250 barrel while holding the barrel in a horizontal position. A meniscus or
curve on the surface of the liquid will appear at the mouth of the FMJ-250 barrel. If there is
difficulty in getting the meniscus or bulge to appear, hold the FMJ-250 barrel so that the mouth
(proximal end) is pointing slightly downward. Place a drop of your test formula or water on the FMJ-
250 Teflon plunger tip and bring the tip into contact with the meniscus. Push the plunger all the
way in and proceed as above.