Delivered Dose Uniformity-DPI
The Delivered Dose Uniformity (DDU) is a critical requirement of in vitro testing of inhaled products to ensure that the correct and accurate dose is delivered to the patient.
Inhaler delivery methods are tested in comparison to a pre-specified standard to confirm that the mass of the active ingredient emitted from the inhaler is consistent to the label claim with each use throughout the container life.
DDCU is tested in individual containers and batches to assess the reliability of mass produced inhalation devices in relation to its written instructions for self-medication.
To gauge the DDU the test device is fired into the sampling apparatus in which the active drug is collected on a filter.
This is then analysed to calculate the emitted dose in single or multi dose applications.