Penn-Century DP-4_4M - Manual (Page 8)

8
Load dry powder ONLY in the Sample Chamber
(= the part that is attached to the delivery tube)
DO NOT load powder in the Air Intake, as it can
interfere with the performance of the device.
Sample Chamber Air Intake
• How to correctly load the Dry Powder Insufflator™ - IMPORTANT!
1. Remove the air syringe or Air Pump from the Insufflator™ prior to loading and weighing it.
2. Before loading, weigh the device empty using a precision balance.
3. Determine the desired dose volume. Use a narrow spatula to place the dry powder dose into the
hole of the Sample Chamber.
4. It is best to simply let the powder fall from the spatula into the Sample Chamber. Take care not to
jab or force the tip of the spatula too deeply into the Sample Chamber, as it may damage the valve
assembly inside it.
5. NEVER load the Air Intake portion of the device with powder, as this may interfere with the
proper function of the Dry Powder Insufflator™.
6. Once the powder is in the Sample Chamber, tap the chamber lightly to settle the sample contents
toward the distal tip. (For the DP-4M, hold the device horizontal after loading and before insertion to
avoid accidentally shaking loose some of the powder sample.)
7. Check to be sure that the connecting surfaces of the tapered joint are free of powder,
8. Re-attach the Sample Chamber to the Air Intake by gently pushing the two halves together. When
re-attaching the two halves, use only enough force to ensure that the connection
between them will not separate when a puff of air is delivered. Pushing the two parts
together forcefully may loosen some of the sample inside and force it out of the delivery
tube. This is particularly of concern when using very small dose volumes. Do not overtighten.
• It may take more than one pulse of air to empty the device
Prior to use in an in-vivo or in-vitro experiment, the user MUST determine what percent of the total dose
is released after one pulse of air. Our experience indicates that more than one pulse of air may be
needed to release 100% of the dose, depending on the characteristics of the powder. Different powder
formulations may behave differently and require more or fewer pulses of air. A powder that is not
hygroscopic, or electrostatic powder may require only one or two pulses to fully clear from the device.
More complex, or larger samples but may require several discrete puffs of air, as many as ten. The user
must take time to learn how many pulses of air will be needed to dispense 100% of the particular
formulation or compound they are using.
• Determining how many air pulses it will take to deliver 100% of your sample
1. First, use a precision balance to determine the exact weight of the device when empty.
2. Weigh the device empty, without the air syringe or Air Pump attached.
3. Load the device with the desired dose and reweigh the device. The new weight should equal the
weight of the empty device plus the weight of your sample.